STENBERG, ATTORNEY GENERAL OF NEBRASKA, et al. v. CARHART

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914 OCTOBER TERM, 1999
Syllabus
STENBERG, ATTORNEY GENERAL OF NEBRASKA,
et al. v. CARHART
certiorari to the united states court of appeals for
the eighth circuit
No. 99–830. Argued April 25, 2000—Decided June 28, 2000
The Constitution offers basic protection to a woman’s right to choose
whether to have an abortion. Roe v. Wade, 410 U. S. 113; Planned Par-
enthood of Southeastern Pa. v. Casey, 505 U. S. 833. Before fetal viabil-
ity, a woman has a right to terminate her pregnancy, id., at 870 (plurality
opinion), and a state law is unconstitutional if it imposes on the woman’s
decision an “undue burden,” i. e., if it has the purpose or effect of placing
a substantial obstacle in the woman’s path, id., at 877. Postviability,
the State, in promoting its interest in the potentiality of human life,
may regulate, and even proscribe, abortion except where “necessary, in
appropriate medical judgment, for the preservation of the [mother’s] life
or health.” E. g., id., at 879. The Nebraska law at issue prohibits any
“partial birth abortion” unless that procedure is necessary to save the
mother’s life. It defines “partial birth abortion” as a procedure in
which the doctor “partially delivers vaginally a living unborn child be-
fore killing the . . . child,” and defines the latter phrase to mean “inten-
tionally delivering into the vagina a living unborn child, or a substantial
portion thereof, for the purpose of performing a procedure that the
[abortionist] knows will kill the . . . child and does kill the . . . child.”
Violation of the law is a felony, and it provides for the automatic revoca-
tion of a convicted doctor’s state license to practice medicine. Respond-
ent Carhart, a Nebraska physician who performs abortions in a clinical
setting, brought this suit seeking a declaration that the statute violates
the Federal Constitution. The District Court held the statute unconsti-
tutional. The Eighth Circuit affirmed.
Held: Nebraska’s statute criminalizing the performance of “partial birth
abortion[s]” violates the Federal Constitution, as interpreted in Casey
and Roe. Pp. 922–946.
(a) Because the statute seeks to ban one abortion method, the Court
discusses several different abortion procedures, as described in the evi-
dence below and the medical literature. During a pregnancy’s second
trimester (12 to 24 weeks), the most common abortion procedure is “dila-
tion and evacuation” (D&E), which involves dilation of the cervix, re-
moval of at least some fetal tissue using nonvacuum surgical instru-
ments, and (after the 15th week) the potential need for instrumental

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915 Cite as: 530 U. S. 914 (2000)
Syllabus
dismemberment of the fetus or the collapse of fetal parts to facilitate
evacuation from the uterus. When such dismemberment is necessary,
it typically occurs as the doctor pulls a portion of the fetus through the
cervix into the birth canal. The risks of mortality and complication
that accompany D&E are significantly lower than those accompanying
induced labor procedures (the next safest midsecond trimester proce-
dures). A variation of D&E, known as “intact D&E,” is used after 16
weeks. It involves removing the fetus from the uterus through the
cervix “intact,” i. e., in one pass rather than several passes. The intact
D&E proceeds in one of two ways, depending on whether the fetus pre-
sents head first or feet first. The feet-first method is known as “dilation
and extraction” (D&X). D&X is ordinarily associated with the term
“partial birth abortion.” The District Court concluded that clear and
convincing evidence established that Carhart’s D&X procedure is supe-
rior to, and safer than, the D&E and other abortion procedures used
during the relevant gestational period in the 10 to 20 cases a year
that present to Carhart. Moreover, materials presented at trial em-
phasize the potential benefits of the D&X procedure in certain cases.
Pp. 923–929.
(b) The Nebraska statute lacks the requisite exception “for the pres-
ervation of the . . . health of the mother.” Casey, supra, at 879 (plural-
ity opinion). The State may promote but not endanger a woman’s
health when it regulates the methods of abortion. Pp. 929–938.
(i) The Court rejects Nebraska’s contention that there is no need
for a health exception here because safe alternatives remain avail-
able and a ban on partial birth abortion/D&X would create no risk
to women’s health. The parties strongly contested this factual ques-
tion in the District Court; and the findings and evidence support
Dr. Carhart. Pp. 931–933.
(ii) Nebraska and its supporting amici respond with eight argu-
ments as to why the District Court’s findings are irrelevant, wrong, or
applicable only in a tiny number of instances. Pp. 933–934.
(iii) The eight arguments are insufficient to demonstrate that Ne-
braska’s law needs no health exception. For one thing, certain of the
arguments are beside the point. The D&X procedure’s relative rarity
(argument (1)) is not highly relevant. The State cannot prohibit a per-
son from obtaining treatment simply by pointing out that most people
do not need it. And the fact that only a “handful” of doctors use the
procedure (argument (2)) may reflect the comparative rarity of late
second term abortions, the procedure’s recent development, the con-
troversy surrounding it, or, as Nebraska suggests, the procedure’s lack
of utility. For another thing, the record responds to Nebraska’s (and
amici’s) medically based arguments. As to argument (3), the District

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916 STENBERG v. CARHART
Syllabus
Court agreed that alternatives such as D&E and induced labor are
“safe,” but found that the D&X method was safer in the circumstances
used by Carhart. As to argument (4)—that testimony showed that the
statutory ban would not increase a woman’s risk of several rare abortion
complications—the District Court simply relied on different expert tes-
timony than the State. Argument (5)—the assertion of amici Associa-
tion of American Physicians and Surgeons et al. that elements of the
D&X procedure may create special risks—is disputed by Carhart’s
amici, including the American College of Obstetricians and Gynecolo-
gists (ACOG), which claims that the suggested alternative procedures
involve similar or greater risks of cervical and uterine injury. Nebras-
ka’s argument (6) is right—there are no general medical studies docu-
menting the comparative safety of the various abortion procedures.
Nor does the Court deny the import of the American Medical Associa-
tion’s (AMA) recommendation (argument (7)) that intact D&X not be
used unless alternative procedures pose materially greater risk to the
woman. However, the Court cannot read ACOG’s qualification that it
could not identify a circumstance where D&X was the “only” life- or
health-preserving option as if, according to Nebraska’s argument (8), it
denied the potential health-related need for D&X. ACOG has also as-
serted that D&X can be the most appropriate abortion procedure and
presents a variety of potential safety advantages. Pp. 934–936.
(iv) The upshot is a District Court finding that D&X obviates
health risks in certain circumstances, a highly plausible record-based
explanation of why that might be so, a division of medical opinion over
whether D&X is generally safer, and an absence of controlled medical
studies that would help answer these medical questions. Given these
circumstances, the Court believes the law requires a health exception.
For one thing, the word “necessary” in Casey’s phrase “necessary, in
appropriate medical judgment, for the . . . health of the mother,” 505
U. S., at 879, cannot refer to absolute proof or require unanimity of medi-
cal opinion. Doctors often differ in their estimation of comparative
health risks and appropriate treatment. And Casey’s words “appro-
priate medical judgment” must embody the judicial need to tolerate re-
sponsible differences of medical opinion. For another thing, the divi-
sion of medical opinion signals uncertainty. If those who believe that
D&X is a safer abortion method in certain circumstances turn out to be
right, the absence of a health exception will place women at an unneces-
sary risk. If they are wrong, the exception will simply turn out to have
been unnecessary. Pp. 936–938.
(c) The Nebraska statute imposes an “undue burden” on a woman’s
ability to choose an abortion. See Casey, supra, at 874 (plurality opin-
ion). Pp. 938–946.

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(i) Nebraska does not deny that the statute imposes an “undue bur-
den” if it applies to the more commonly used D&E procedure as well
as to D&X. This Court agrees with the Eighth Circuit that the D&E
procedure falls within the statutory prohibition of intentionally deliver-
ing into the vagina a living fetus, or “a substantial portion thereof,” for
the purpose of performing a procedure that the perpetrator knows will
kill the fetus. Because the evidence makes clear that D&E will often
involve a physician pulling an arm, leg, or other “substantial portion” of
a still living fetus into the vagina prior to the fetus’ death, the statutory
terms do not to distinguish between D&X and D&E. The statute’s lan-
guage does not track the medical differences between D&E and D&X,
but covers both. Using the law’s statutory terms, it is impossible to
distinguish between D&E (where a foot or arm is drawn through the
cervix) and D&X (where the body up to the head is drawn through the
cervix). Both procedures can involve the introduction of a “substantial
portion” of a still living fetus, through the cervix, into the vagina—the
very feature of an abortion that leads to characterizing such a procedure
as involving “partial birth.” Pp. 938–940.
(ii) The Court rejects the Nebraska Attorney General’s arguments
that the state law does differentiate between the two procedures—i. e.,
that the words “substantial portion” mean “the child up to the head,”
such that the law is inapplicable where the physician introduces into the
birth canal anything less than the entire fetal body—and that the Court
must defer to his views. The Court’s case law makes clear that the
Attorney General’s narrowing interpretation cannot be given control-
ling weight. For one thing, this Court normally follows lower federal-
court interpretations of state law, e. g., McMillian v. Monroe County,
520 U. S. 781, 786, and rarely reviews such an interpretation that is
agreed upon by the two lower federal courts. Virginia v. American
Booksellers Assn., Inc., 484 U. S. 383, 395. Here, the two lower courts
both rejected the Attorney General’s narrowing interpretation. For
another, the Court’s precedent warns against accepting as “authorita-
tive” an Attorney General’s interpretation of state law where, as here,
that interpretation does not bind the state courts or local law enforce-
ment. In Nebraska, elected county attorneys have independent author-
ity to initiate criminal prosecutions. Some present prosecutors (and
future Attorneys General) might use the law at issue to pursue physi-
cians who use D&E procedures. Nor can it be said that the lower
courts used the wrong legal standard in assessing the Attorney Gener-
al’s interpretation. The Eighth Circuit recognized its duty to give the
law a construction that would avoid constitutional doubt, but nonethe-
less concluded that the Attorney General’s interpretation would twist
the law’s words, giving them a meaning they cannot reasonably bear.

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918 STENBERG v. CARHART
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The Eighth Circuit is far from alone in rejecting such a narrowing inter-
pretation, since 11 of the 12 federal courts that have interpreted on the
merits the model statutory language on which the Nebraska law is based
have found the language potentially applicable to abortion procedures
other than D&X. Regardless, were the Court to grant the Attorney
General’s views “substantial weight,” it would still have to reject his
interpretation, for it conflicts with the statutory language. The statu-
tory words, “substantial portion,” indicate that the statute does not
include the Attorney General’s restriction—“the child up to the head.”
The Nebraska Legislature’s debates hurt the Attorney General’s argu-
ment more than they help it, indicating that as small a portion of the
fetus as a foot would constitute a “substantial portion.” Even assuming
that the distinction the Attorney General seeks to draw between the
overall abortion procedure itself and the separate procedure used to kill
an unborn child would help him make the D&E/D&X distinction he
seeks, there is no language in the statute that supports it. Although
adopting his interpretation might avoid the constitutional problem dis-
cussed above, the Court lacks power do so where, as here, the narrow-
ing construction is not reasonable and readily apparent. E. g., Boos v.
Barry, 485 U. S. 312, 330. Finally, the Court has never held that a
federal litigant must await a state-court construction or the develop-
ment of an established practice before bringing the federal suit. City
of Lakewood v. Plain Dealer Publishing Co., 486 U. S. 750, 770, n. 11.
But any authoritative state-court construction is lacking here. The At-
torney General neither sought a narrowing interpretation from the Ne-
braska Supreme Court nor asked the federal courts to certify the inter-
pretive question. Cf. Arizonans for Official English v. Arizona, 520
U. S. 43. Even were the Court inclined to certify the question now, it
could not do so because certification is appropriate only where the stat-
ute is “fairly susceptible” to a narrowing construction, see Houston v.
Hill, 482 U. S. 451, 468–471, as is not the case here. Moreover, the
Nebraska Supreme Court grants certification only if the certified ques-
tion is determinative of the cause, see id., at 471, as it would not be
here. In sum, because all those who perform abortion procedures using
the D&E method must fear prosecution, conviction, and imprisonment,
the Nebraska law imposes an undue burden upon a woman’s right to
make an abortion decision. Pp. 940–946.
192 F. 3d 1142, affirmed.
Breyer, J., delivered the opinion of the Court, in which Stevens,
O’Connor, Souter, and Ginsburg, JJ., joined. Stevens, J., filed a con-
curring opinion, in which Ginsburg, J., joined, post, p. 946. O’Connor,
J., filed a concurring opinion, post, p. 947. Ginsburg, J., filed a concurring

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919 Cite as: 530 U. S. 914 (2000)
Syllabus
opinion, in which Stevens, J., joined, post, p. 951. Rehnquist, C. J., post,
p. 952, and Scalia, J., post, p. 953, filed dissenting opinions. Kennedy,
J., filed a dissenting opinion, in which Rehnquist, C. J., joined, post, p. 956.
Thomas, J., filed a dissenting opinion, in which Rehnquist, C. J., and
Scalia, J., joined, post, p. 980.
Don Stenberg, Attorney General of Nebraska, pro se, ar-
gued the cause for petitioners. With him on the briefs was
L. Steven Grasz, Deputy Attorney General.
Simon Heller argued the cause for respondent. With him
on the brief were Janet Benshoof, Priscilla J. Smith, Bonnie
Scott Jones, Jerry M. Hug, and Alan G. Stoler.*
*Briefs of amici curiae urging reversal were filed for the State of Loui-
siana et al. by Richard P. Ieyoub, Attorney General of Louisiana, Roy A.
Mongrue, Jr., Assistant Attorney General, Dorinda C. Bordlee, Special
Assistant Attorney General, Mike Moore, Attorney General of Mississippi,
Nikolas T. Nikas, and Stephen M. Crampton; for the State of Texas by
John Cornyn, Attorney General, Andy Taylor, First Assistant Attorney
General, Linda S. Eads, Deputy Attorney General, Gregory S. Coleman,
Solicitor General, and Julie Caruthers Parsley, Deputy Solicitor General;
for the State of Wisconsin by James E. Doyle, Attorney General, and
Susan K. Ullman, Assistant Attorney General; for Agudath Israel of
America by David Zwiebel; for the American Center for Law and Justice
et al. by Jay Alan Sekulow, James M. Henderson, Sr., Walter M. Weber,
Thomas P. Monaghan, Richard Thompson, and Edward L. White III; for
the Association of American Physicians and Surgeons et al. by Teresa
Stanton Collett; for Family First by Paul Benjamin Linton; for Feminists
for Life of America et al. by Dwight G. Duncan; for the Knights of Colum-
bus by Pat A. Cipollone and Carl A. Anderson; for the National Associa-
tion of Prolife Nurses, Inc., by William C. Porth and Robert P. George; for
the National Right to Life Committee by James Bopp, Jr., Richard E.
Coleson, and Thomas J. Marzen; for the Rutherford Institute by Thomas
W. Strahan, John W. Whitehead, and Steven H. Aden; for the United
States Catholic Conference et al. by Mark E. Chopko and Michael F.
Moses; and for Representative Charles T. Canady et al. by James Bopp,
Jr., Richard E. Coleson, and Thomas J. Marzen.
Briefs of amici curiae urging affirmance were filed for the United
States by Solicitor General Waxman, Deputy Solicitor General Under-
wood, Paul R. Q. Wolfson, Harriet S. Rabb, Marcy J. Wilder, and Kenneth
Y. Choe; for the State of California by Bill Lockyer, Attorney General,
Peter J. Siggins, Chief Deputy Attorney General, and Patricia A. Wynne,

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920 STENBERG v. CARHART
Opinion of the Court
Justice Breyer delivered the opinion of the Court.
We again consider the right to an abortion. We under-
stand the controversial nature of the problem. Millions of
Americans believe that life begins at conception and conse-
quently that an abortion is akin to causing the death of an
innocent child; they recoil at the thought of a law that would
permit it. Other millions fear that a law that forbids abor-
tion would condemn many American women to lives that lack
dignity, depriving them of equal liberty and leading those
with least resources to undergo illegal abortions with the
attendant risks of death and suffering. Taking account of
Special Assistant Attorney General; for the State of New York et al. by
Eliot Spitzer, Attorney General of New York, Preeta D. Bansal, Solicitor
General, and Jennifer K. Brown, Assistant Attorney General, Andrew
Ketterer, Attorney General of Maine, Hardy Myers, Attorney General of
Oregon, and William H. Sorrell, Attorney General of Vermont; for the
American Civil Liberties Union et al. by Catherine Weiss, Steven R. Sha-
piro, and Colleen K. Connell; for the American College of Obstetricians
and Gynecologists et al. by Adam L. Frank, A. Stephen Hut, Jr., and
Matthew A. Brill; for the Naral Foundation et al. by James P. Joseph,
Nancy L. Perkins, and Elizabeth Arndorfer; for Planned Parenthood of
Wisconsin et al. by Roger K. Evans, Eve C. Gartner, and Dara Klassel;
for the Religious Coalition for Reproductive Choice et al. by Carrie Y.
Flaxman; for Seventy-five Organizations Committed to Women’s Equality
by Susan Frietsche, Carol E. Tracy, Martha F. Davis, Roslyn Powell, and
Yolanda S. Wu; and for Senator Barbara Boxer et al. by Robert Lewin,
Kevin J. Curnin, Claude G. Szyfer, and Robert Abrams.
Briefs of amici curiae were filed by the Commonwealth of Virginia et al.
by Mark L. Earley, Attorney General of Virginia, William H. Hurd, So-
licitor General, and Daniel J. Poynor, Alison P. Landry, and Anthony
P. Meredith, Assistant Attorneys General, Claire J. V. Richards, James
Bopp, Jr., Richard E. Coleson, Thomas J. Marzen, Richard F. Collier, Jr.,
and by the Attorneys General for their respective States as follows: Bill
Pryor of Alabama, Alan G. Lance of Idaho, James E. Ryan of Illinois,
Thomas J. Miller of Iowa, Jennifer M. Granholm of Michigan, Heidi Heit-
kamp of North Dakota, Betty D. Montgomery of Ohio, D. Michael Fisher
of Pennsylvania, Charlie Condon of South Carolina, Mark Barnett of
South Dakota, and Jan Graham of Utah; and for the Family Research
Council by Teresa R. Wagner.

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Opinion of the Court
these virtually irreconcilable points of view, aware that con-
stitutional law must govern a society whose different mem-
bers sincerely hold directly opposing views, and considering
the matter in light of the Constitution’s guarantees of funda-
mental individual liberty, this Court, in the course of a gen-
eration, has determined and then redetermined that the Con-
stitution offers basic protection to the woman’s right to
choose. Roe v. Wade, 410 U. S. 113 (1973); Planned Parent-
hood of Southeastern Pa. v. Casey, 505 U. S. 833 (1992). We
shall not revisit those legal principles. Rather, we apply
them to the circumstances of this case.
Three established principles determine the issue before us.
We shall set them forth in the language of the joint opinion
in Casey. First, before “viability . . . the woman has a right
to choose to terminate her pregnancy.” Id., at 870 (plural-
ity opinion).
Second, “a law designed to further the State’s interest in
fetal life which imposes an undue burden on the woman’s
decision before fetal viability” is unconstitutional. Id., at
877. An “undue burden is . . . shorthand for the conclusion
that a state regulation has the purpose or effect of placing a
substantial obstacle in the path of a woman seeking an abor-
tion of a nonviable fetus.” Ibid.
Third, “ ‘subsequent to viability, the State in promoting its
interest in the potentiality of human life may, if it chooses,
regulate, and even proscribe, abortion except where it is nec-
essary, in appropriate medical judgment, for the preserva-
tion of the life or health of the mother.’ ” Id., at 879 (quoting
Roe v. Wade, supra, at 164–165).
We apply these principles to a Nebraska law banning “par-
tial birth abortion.” The statute reads as follows:
“No partial birth abortion shall be performed in this
state, unless such procedure is necessary to save the life
of the mother whose life is endangered by a physical
disorder, physical illness, or physical injury, including
a life-endangering physical condition caused by or aris-

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922 STENBERG v. CARHART
Opinion of the Court
ing from the pregnancy itself.” Neb. Rev. Stat. Ann.
§ 28–328(1) (Supp. 1999).
The statute defines “partial birth abortion” as:
“an abortion procedure in which the person performing
the abortion partially delivers vaginally a living unborn
child before killing the unborn child and completing the
delivery.” § 28–326(9).
It further defines “partially delivers vaginally a living un-
born child before killing the unborn child” to mean
“deliberately and intentionally delivering into the va-
gina a living unborn child, or a substantial portion
thereof, for the purpose of performing a procedure that
the person performing such procedure knows will kill
the unborn child and does kill the unborn child.” Ibid.
The law classifies violation of the statute as a “Class III fel-
ony” carrying a prison term of up to 20 years, and a fine of up
to $25,000. §§ 28–328(2), 28–105. It also provides for the
automatic revocation of a doctor’s license to practice medi-
cine in Nebraska. § 28–328(4).
We hold that this statute violates the Constitution.
I
A
Dr. Leroy Carhart is a Nebraska physician who performs
abortions in a clinical setting. He brought this lawsuit in
Federal District Court seeking a declaration that the Ne-
braska statute violates the Federal Constitution, and asking
for an injunction forbidding its enforcement. After a trial
on the merits, during which both sides presented several
expert witnesses, the District Court held the statute uncon-
stitutional. 11 F. Supp. 2d 1099 (Neb. 1998). On appeal, the
Eighth Circuit affirmed. 192 F. 3d 1142 (1999); cf. Hope
Clinic v. Ryan, 195 F. 3d 857 (CA7 1999) (en banc) (consider-

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Opinion of the Court
ing a similar statute, but reaching a different legal conclu-
sion). We granted certiorari to consider the matter.
B
Because Nebraska law seeks to ban one method of abort-
ing a pregnancy, we must describe and then discuss several
different abortion procedures. Considering the fact that
those procedures seek to terminate a potential human life,
our discussion may seem clinically cold or callous to some,
perhaps horrifying to others. There is no alternative way,
however, to acquaint the reader with the technical distinc-
tions among different abortion methods and related factual
matters, upon which the outcome of this case depends. For
that reason, drawing upon the findings of the trial court,
underlying testimony, and related medical texts, we shall
describe the relevant methods of performing abortions in
technical detail.
The evidence before the trial court, as supported or sup-
plemented in the literature, indicates the following:
1. About 90% of all abortions performed in the United
States take place during the first trimester of pregnancy,
before 12 weeks of gestational age. Centers for Disease
Control and Prevention, Abortion Surveillance—United
States, 1996, p. 41 (July 30, 1999) (hereinafter Abortion
Surveillance). During the first trimester, the predominant
abortion method is “vacuum aspiration,” which involves in-
sertion of a vacuum tube (cannula) into the uterus to evacu-
ate the contents. Such an abortion is typically performed
on an outpatient basis under local anesthesia. 11 F. Supp.
2d, at 1102; Obstetrics: Normal & Problem Pregnancies
1253–1254 (S. Gabbe, J. Niebyl, & J. Simpson eds. 3d ed.
1996). Vacuum aspiration is considered particularly safe.
The procedure’s mortality rates for first trimester abortion
are, for example, 5 to 10 times lower than those associated
with carrying the fetus to term. Complication rates are also
low. Id., at 1251; Lawson et al., Abortion Mortality, United

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924 STENBERG v. CARHART
Opinion of the Court
States, 1972 through 1987, 171 Am. J. Obstet. Gynecol. 1365,
1368 (1994); M. Paul et al., A Clinicians Guide to Medical
and Surgical Abortion 108–109 (1999) (hereinafter Medi-
cal and Surgical Abortion). As the fetus grows in size, how-
ever, the vacuum aspiration method becomes increasingly
difficult to use. 11 F. Supp. 2d, at 1102–1103; Obstetrics:
Normal & Problem Pregnancies, supra, at 1268.
2. Approximately 10% of all abortions are performed dur-
ing the second trimester of pregnancy (12 to 24 weeks).
Abortion Surveillance 41. In the early 1970’s, inducing
labor through the injection of saline into the uterus was the
predominant method of second trimester abortion. Id., at 8;
Planned Parenthood of Central Mo. v. Danforth, 428 U. S.
52, 76 (1976). Today, however, the medical profession has
switched from medical induction of labor to surgical proce-
dures for most second trimester abortions. The most com-
monly used procedure is called “dilation and evacuation”
(D&E). That procedure (together with a modified form
of vacuum aspiration used in the early second trimester)
accounts for about 95% of all abortions performed from 12
to 20 weeks of gestational age. Abortion Surveillance 41.
3. D&E “refers generically to transcervical procedures
performed at 13 weeks gestation or later.” American Medi-
cal Association, Report of Board of Trustees on Late-Term
Abortion, App. 490 (hereinafter AMA Report). The AMA
Report, adopted by the District Court, describes the process
as follows.
Between 13 and 15 weeks of gestation:
“D&E is similar to vacuum aspiration except that the
cervix must be dilated more widely because surgical in-
struments are used to remove larger pieces of tissue.
Osmotic dilators are usually used. Intravenous fluids
and an analgesic or sedative may be administered. A
local anesthetic such as a paracervical block may be
administered, dilating agents, if used, are removed and
instruments are inserted through the cervix into the

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Opinion of the Court
uterus to removal fetal and placental tissue. Because
fetal tissue is friable and easily broken, the fetus may
not be removed intact. The walls of the uterus are
scraped with a curette to ensure that no tissue remains.”
Id., at 490–491.
After 15 weeks:
“Because the fetus is larger at this stage of gestation
(particularly the head), and because bones are more
rigid, dismemberment or other destructive procedures
are more likely to be required than at earlier gestational
ages to remove fetal and placental tissue.” Id., at 491.
After 20 weeks:
“Some physicians use intrafetal potassium chloride or
digoxin to induce fetal demise prior to a late D&E (after
20 weeks), to facilitate evacuation.” Id., at 491–492.
There are variations in D&E operative strategy; compare
ibid. with W. Hern, Abortion Practice 146–156 (1984), and
Medical and Surgical Abortion 133–135. However, the com-
mon points are that D&E involves (1) dilation of the cervix;
(2) removal of at least some fetal tissue using nonvacuum
instruments; and (3) (after the 15th week) the potential need
for instrumental disarticulation or dismemberment of the
fetus or the collapse of fetal parts to facilitate evacuation
from the uterus.
4. When instrumental disarticulation incident to D&E is
necessary, it typically occurs as the doctor pulls a portion of
the fetus through the cervix into the birth canal. Dr. Car-
hart testified at trial as follows:
“Dr. Carhart: . . . ‘The dismemberment occurs between
the traction of . . . my instrument and the counter-
traction of the internal os of the cervix . . . .
“Counsel: ‘So the dismemberment occurs after you
pulled a part of the fetus through the cervix, is that
correct?

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“Dr. Carhart: ‘Exactly. Because you’re using—The cer-
vix has two strictures or two rings, the internal os and
the external os . . . that’s what’s actually doing the
dismembering. . . .
“Counsel: ‘When we talked before or talked before
about a D&E, that is not—where there is not intention
to do it intact, do you, in that situation, dismember the
fetus in utero first, then remove portions?
“Dr. Carhart: ‘I don’t think so. . . . I don’t know of any
way that one could go in and intentionally dismember
the fetus in the uterus. . . . It takes something that
restricts the motion of the fetus against what you’re
doing before you’re going to get dismemberment.’ ” 11
F. Supp. 2d, at 1104.
Dr. Carhart’s specification of the location of fetal disarticula-
tion is consistent with other sources. See Medical and Sur-
gical Abortion 135; App. in Nos. 98–3245 and 98–3300 (CA8),
p. 683, (testimony of Dr. Phillip Stubblefield) (“Q: So you
don’t actually dismember the fetus in utero, then take the
pieces out? A: No”).
5. The D&E procedure carries certain risks. The use of
instruments within the uterus creates a danger of accidental
perforation and damage to neighboring organs. Sharp fetal
bone fragments create similar dangers. And fetal tissue ac-
cidentally left behind can cause infection and various other
complications. See 11 F. Supp. 2d, at 1110; Gynecologic, Ob-
stetric, and Related Surgery 1045 (D. Nichols & D. Clarke-
Pearson eds. 2d ed. 2000); F. Cunningham et al., Williams
Obstetrics 598 (20th ed. 1997). Nonetheless studies show
that the risks of mortality and complication that accompany
the D&E procedure between the 12th and 20th weeks of ges-
tation are significantly lower than those accompanying in-
duced labor procedures (the next safest midsecond trimester
procedures). See Gynecologic, Obstetric, and Related Sur-
gery, supra, at 1046; AMA Report, App. 495, 496; Medical

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and Surgical Abortion 139, 142; Lawson, 171 Am. J. Obstet.
Gynecol., at 1368.
6. At trial, Dr. Carhart and Dr. Stubblefield described a
variation of the D&E procedure, which they referred to as
an “intact D&E.” See 11 F. Supp. 2d, at 1105, 1111. Like
other versions of the D&E technique, it begins with induced
dilation of the cervix. The procedure then involves remov-
ing the fetus from the uterus through the cervix “intact,”
i. e., in one pass, rather than in several passes. Ibid. It is
used after 16 weeks at the earliest, as vacuum aspiration
becomes ineffective and the fetal skull becomes too large to
pass through the cervix. Id., at 1105. The intact D&E pro-
ceeds in one of two ways, depending on the presentation of
the fetus. If the fetus presents head first (a vertex presen-
tation), the doctor collapses the skull; and the doctor then
extracts the entire fetus through the cervix. If the fetus
presents feet first (a breech presentation), the doctor pulls
the fetal body through the cervix, collapses the skull, and
extracts the fetus through the cervix. Ibid. The breech
extraction version of the intact D&E is also known com-
monly as “dilation and extraction,” or D&X. Id., at 1112.
In the late second trimester, vertex, breech, and traverse/
compound (sideways) presentations occur in roughly similar
proportions. Medical and Surgical Abortion 135; 11 F. Supp.
2d, at 1108.
7. The intact D&E procedure can also be found described
in certain obstetric and abortion clinical textbooks, where
two variations are recognized. The first, as just described,
calls for the physician to adapt his method for extracting the
intact fetus depending on fetal presentation. See Gyneco-
logic, Obstetric, and Related Surgery, supra, at 1043; Medical
and Surgical Abortion 136–137. This is the method used by
Dr. Carhart. See 11 F. Supp. 2d, at 1105. A slightly differ-
ent version of the intact D&E procedure, associated with
Dr. Martin Haskell, calls for conversion to a breech presenta-
tion in all cases. See Gynecologic, Obstetric, and Related

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Surgery, supra, at 1043 (citing M. Haskell, Dilation and Ex-
traction for Late Second Trimester Abortion (1992), in 139
Cong. Rec. 8605 (1993)).
8. The American College of Obstetricians and Gynecolo-
gists describes the D&X procedure in a manner correspond-
ing to a breech-conversion intact D&E, including the follow-
ing steps:
“1. deliberate dilatation of the cervix, usually over a
sequence of days;
“2. instrumental conversion of the fetus to a footling
breech;
“3. breech extraction of the body excepting the head;
and
“4. partial evacuation of the intracranial contents of
a living fetus to effect vaginal delivery of a dead but
otherwise intact fetus.” American College of Obste-
tricians and Gynecologists Executive Board, Statement
on Intact Dilation and Extraction (Jan. 12, 1997) (here-
inafter ACOG Statement), App. 599–560.
Despite the technical differences we have just described, in-
tact D&E and D&X are sufficiently similar for us to use the
terms interchangeably.
9. Dr. Carhart testified he attempts to use the intact
D&E procedure during weeks 16 to 20 because (1) it reduces
the dangers from sharp bone fragments passing through the
cervix, (2) minimizes the number of instrument passes
needed for extraction and lessens the likelihood of uterine
perforations caused by those instruments, (3) reduces the
likelihood of leaving infection-causing fetal and placental tis-
sue in the uterus, and (4) could help to prevent potentially
fatal absorption of fetal tissue into the maternal circulation.
See 11 F. Supp. 2d, at 1107. The District Court made no
findings about the D&X procedure’s overall safety. Id., at
1126, n. 39. The District Court concluded, however, that
“the evidence is both clear and convincing that Carhart’s

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D&X procedure is superior to, and safer than, the . . . other
abortion procedures used during the relevant gestational pe-
riod in the 10 to 20 cases a year that present to Dr. Carhart.”
Id., at 1126.
10. The materials presented at trial referred to the poten-
tial benefits of the D&X procedure in circumstances involv-
ing nonviable fetuses, such as fetuses with abnormal fluid
accumulation in the brain (hydrocephaly). See 11 F. Supp.
2d, at 1107 (quoting AMA Report, App. 492 (“ ‘Intact D&X
may be preferred by some physicians, particularly when the
fetus has been diagnosed with hydrocephaly or other anoma-
lies incompatible with life outside the womb’ ”)); see also
Grimes, The Continuing Need for Late Abortions, 280 JAMA
747, 748 (Aug. 26, 1998) (D&X “may be especially useful in
the presence of fetal anomalies, such as hydrocephalus,” be-
cause its reduction of the cranium allows “a smaller diameter
to pass through the cervix, thus reducing risk of cervical
injury”). Others have emphasized its potential for women
with prior uterine scars, or for women for whom induction
of labor would be particularly dangerous. See Women’s
Medical Professional Corp. v. Voinovich, 911 F. Supp. 2d
1051, 1067 (SD Ohio 1995); Evans v. Kelley, 977 F. Supp. 2d
1283, 1296 (ED Mich. 1997).
11. There are no reliable data on the number of D&X abor-
tions performed annually. Estimates have ranged between
640 and 5,000 per year. Compare Henshaw, Abortion Inci-
dence and Services in the United States, 1995–1996, 30 Fam-
ily Planning Perspectives 263, 268 (1998), with Joint Hearing
on S. 6 and H. R. 929 before the Senate Committee on the
Judiciary and the Subcommittee on the Constitution of the
House Committee on the Judiciary, 105th Cong., 1st Sess.,
46 (1997).
II
The question before us is whether Nebraska’s statute,
making criminal the performance of a “partial birth abor-
tion,” violates the Federal Constitution, as interpreted in

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Planned Parenthood of Southeastern Pa. v. Casey, 505 U. S.
833 (1992), and Roe v. Wade, 410 U. S. 113 (1973). We con-
clude that it does for at least two independent reasons.
First, the law lacks any exception “ ‘for the preservation of
the . . . health of the mother.’ ” Casey, 505 U. S., at 879 (plu-
rality opinion). Second, it “imposes an undue burden on a
woman’s ability” to choose a D&E abortion, thereby unduly
burdening the right to choose abortion itself. Id., at 874.
We shall discuss each of these reasons in turn.
A
The Casey plurality opinion reiterated what the Court held
in Roe; that “ ‘subsequent to viability, the State in promoting
its interest in the potentiality of human life may, if it chooses,
regulate, and even proscribe, abortion except where it is nec-
essary, in appropriate medical judgment, for the preserva-
tion of the life or health of the mother.’ ” 505 U. S., at 879
(quoting Roe, supra, at 164–165) (emphasis added).
The fact that Nebraska’s law applies both previability and
postviability aggravates the constitutional problem pre-
sented. The State’s interest in regulating abortion previa-
bility is considerably weaker than postviability. See Casey,
supra, at 870. Since the law requires a health exception in
order to validate even a postviability abortion regulation, it
at a minimum requires the same in respect to previability
regulation. See Casey, supra, at 880 (majority opinion)
(assuming need for health exception previability); see also
Harris v. McRae, 448 U. S. 297, 316 (1980).
The quoted standard also depends on the state regulations
“promoting [the State’s] interest in the potentiality of human
life.” The Nebraska law, of course, does not directly further
an interest “in the potentiality of human life” by saving the
fetus in question from destruction, as it regulates only a
method of performing abortion. Nebraska describes its in-
terests differently. It says the law “ ‘show[s] concern for the
life of the unborn,’ ” “prevent[s] cruelty to partially born chil-

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dren,” and “preserve[s] the integrity of the medical profes-
sion.” Brief for Petitioners 48. But we cannot see how the
interest-related differences could make any difference to the
question at hand, namely, the application of the “health”
requirement.
Consequently, the governing standard requires an excep-
tion “where it is necessary, in appropriate medical judgment
for the preservation of the life or health of the mother,”
Casey, supra, at 879, for this Court has made clear that a
State may promote but not endanger a woman’s health when
it regulates the methods of abortion. Thornburgh v. Ameri-
can College of Obstetricians and Gynecologists, 476 U. S.
747, 768–769 (1986); Colautti v. Franklin, 439 U. S. 379, 400
(1979); Danforth, 428 U. S., at 76–79; Doe v. Bolton, 410 U. S.
179, 197 (1973).
Justice Thomas says that the cases just cited limit this
principle to situations where the pregnancy itself creates a
threat to health. See post, at 1010. He is wrong. The
cited cases, reaffirmed in Casey, recognize that a State can-
not subject women’s health to significant risks both in that
context, and also where state regulations force women to
use riskier methods of abortion. Our cases have repeatedly
invalidated statutes that in the process of regulating the
methods of abortion, imposed significant health risks. They
make clear that a risk to a women’s health is the same
whether it happens to arise from regulating a particular
method of abortion, or from barring abortion entirely. Our
holding does not go beyond those cases, as ratified in Casey.
1
Nebraska responds that the law does not require a health
exception unless there is a need for such an exception. And
here there is no such need, it says. It argues that “safe
alternatives remain available” and “a ban on partial-birth
abortion/D&X would create no risk to the health of women.”
Brief for Petitioners 29, 40. The problem for Nebraska is

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that the parties strongly contested this factual question in
the trial court below; and the findings and evidence support
Dr. Carhart. The State fails to demonstrate that banning
D&X without a health exception may not create significant
health risks for women, because the record shows that sig-
nificant medical authority supports the proposition that in
some circumstances, D&X would be the safest procedure.
We shall reiterate in summary form the relevant findings
and evidence. On the basis of medical testimony the Dis-
trict Court concluded that “Carhart’s D&X procedure is . . .
safer tha[n] the D&E and other abortion procedures used
during the relevant gestational period in the 10 to 20 cases
a year that present to Dr. Carhart.” 11 F. Supp. 2d, at 1126.
It found that the D&X procedure permits the fetus to pass
through the cervix with a minimum of instrumentation.
Ibid. It thereby
“reduces operating time, blood loss and risk of infection;
reduces complications from bony fragments; reduces
instrument-inflicted damage to the uterus and cervix;
prevents the most common causes of maternal mortality
(DIC and amniotic fluid embolus); and eliminates the
possibility of ‘horrible complications’ arising from re-
tained fetal parts.” Ibid.
The District Court also noted that a select panel of the
American College of Obstetricians and Gynecologists con-
cluded that D&X “ ‘may be the best or most appropriate pro-
cedure in a particular circumstance to save the life or pre-
serve the health of a woman.’ ” Id., at 1105, n. 10 (quoting
ACOG Statement, App. 600–601) (but see an important qual-
ification, infra, at 934). With one exception, the federal
trial courts that have heard expert evidence on the matter
have reached similar factual conclusions. See Rhode Island
Medical Soc. v. Whitehouse, 66 F. Supp. 2d 288, 314 (RI
1999); A Choice for Women v. Butterworth, 54 F. Supp. 2d
1148, 1153, 1156 (SD Fla. 1998); Causeway Medical Suite v.
Foster, 43 F. Supp. 2d 604, 613–614 (ED La. 1999); Richmond

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Medical Center for Women v. Gilmore, 11 F. Supp. 2d 795,
827, n. 40 (ED Va. 1998); Hope Clinic v. Ryan, 995 F. Supp.
2d 847, 852 (ND Ill. 1998), vacated, 195 F. 3d 857 (CA7 1999),
cert. pending, No. 99–1152; Voinovich, 911 F. Supp. 2d, at
1069–1070; Kelley, 977 F. Supp. 2d, at 1296; but see Planned
Parenthood of Wis. v. Doyle, 44 F. Supp. 2d 975, 980 (WD
Wis.), vacated, 195 F. 3d 857 (CA7 1999).
2
Nebraska, along with supporting amici, replies that these
findings are irrelevant, wrong, or applicable only in a tiny
number of instances. It says (1) that the D&X procedure is
“little-used,” (2) by only “a handful of doctors.” Brief for
Petitioners 32. It argues (3) that D&E and labor induction
are at all times “safe alternative procedures.” Id., at 36.
It refers to the testimony of petitioners’ medical expert, who
testified (4) that the ban would not increase a woman’s risk
of several rare abortion complications (disseminated intra-
vascular coagulopathy and amniotic fluid embolus), id., at 37;
App. 642–644.
The Association of American Physicians and Surgeons
et al., amici supporting Nebraska, argue (5) that elements of
the D&X procedure may create special risks, including cervi-
cal incompetence caused by overdilitation, injury caused by
conversion of the fetal presentation, and dangers arising
from the “blind” use of instrumentation to pierce the fetal
skull while lodged in the birth canal. See Brief for Associa-
tion of American Physicians and Surgeons et al. as Amici
Curiae 21–23; see also Sprang & Neerhof, Rationale for Ban-
ning Abortions Late in Pregnancy, 280 JAMA 744, 746 (Aug.
26, 1998).
Nebraska further emphasizes (6) that there are no medical
studies “establishing the safety of the partial-birth abortion/
D&X procedure,” Brief for Petitioners 39, and “no medical
studies comparing the safety of partial-birth abortion/D&X
to other abortion procedures,” ibid. It points to, id., at 35,

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(7) an American Medical Association policy statement that
“ ‘there does not appear to be any identified situation in
which intact D&X is the only appropriate procedure to in-
duce abortion,’ ” Late Term Pregnancy Termination Tech-
niques, AMA Policy H–5.982 (1997). And it points out (8)
that the American College of Obstetricians and Gynecolo-
gists qualified its statement that D&X “may be the best or
most appropriate procedure,” by adding that the panel
“could identify no circumstances under which [the D&X]
procedure . . . would be the only option to save the life or
preserve the health of the woman.” App. 600–601.
3
We find these eight arguments insufficient to demonstrate
that Nebraska’s law needs no health exception. For one
thing, certain of the arguments are beside the point. The
D&X procedure’s relative rarity (argument (1)) is not highly
relevant. The D&X is an infrequently used abortion proce-
dure; but the health exception question is whether pro-
tecting women’s health requires an exception for those
infrequent occasions. A rarely used treatment might be
necessary to treat a rarely occurring disease that could
strike anyone—the State cannot prohibit a person from ob-
taining treatment simply by pointing out that most people
do not need it. Nor can we know whether the fact that only
a “handful” of doctors use the procedure (argument (2)) re-
flects the comparative rarity of late second term abortions,
the procedure’s recent development, Gynecologic, Obstetric,
and Related Surgery, at 1043, the controversy surrounding
it, or, as Nebraska suggests, the procedure’s lack of utility.
For another thing, the record responds to Nebraska’s (and
amici’s) medically based arguments. In respect to argu-
ment (3), for example, the District Court agreed that alterna-
tives, such as D&E and induced labor, are “safe” but found
that the D&X method was significantly safer in certain cir-
cumstances. 11 F. Supp. 2d, at 1125–1126. In respect to

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argument (4), the District Court simply relied on different
expert testimony—testimony stating that “ ‘[a]nother advan-
tage of the Intact D&E is that it eliminates the risk of embo-
lism of cerebral tissue into the woman’s blood stream.’ ” Id.,
at 1124 (quoting Hearing on H. R. 1833 before the Senate
Committee on the Judiciary, 104th Cong., 1st Sess., 260 (1995)
(statement of W. Hern).
In response to amici’s argument (5), the American College
of Obstetricians and Gynecologists, in its own amici brief,
denies that D&X generally poses risks greater than the al-
ternatives. It says that the suggested alternative proce-
dures involve similar or greater risks of cervical and uterine
injury, for “D&E procedures, involve similar amounts of dili-
tation” and “of course childbirth involves even greater cervi-
cal dilitation.” Brief for American College of Obstetricians
and Gynecologists et al. as Amici Curiae 23. The College
points out that Dr. Carhart does not reposition the fetus
thereby avoiding any risks stemming from conversion to
breech presentation, and that, as compared with D&X, D&E
involves the same, if not greater, “blind” use of sharp instru-
ments in the uterine cavity. Id., at 23–24.
We do not quarrel with Nebraska’s argument (6), for
Nebraska is right. There are no general medical studies
documenting comparative safety. Neither do we deny the
import of the American Medical Association’s statement
(argument (7))—even though the State does omit the remain-
der of that statement: “The AMA recommends that the pro-
cedure not be used unless alternative procedures pose mate-
rially greater risk to the woman.” Late Term Pregnancy
Termination Techniques, AMA Policy H–5.982 (emphasis
added).
We cannot, however, read the American College of Obste-
tricians and Gynecologists panel’s qualification (that it could
not “identify” a circumstance where D&X was the “only”
life- or health-preserving option) as if, according to Nebras-
ka’s argument (8), it denied the potential health-related need

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for D&X. That is because the College writes the following
in its amici brief:
“Depending on the physician’s skill and experience,
the D&X procedure can be the most appropriate abor-
tion procedure for some women in some circumstances.
D&X presents a variety of potential safety advantages
over other abortion procedures used during the same
gestational period. Compared to D&Es involving dis-
memberment, D&X involves less risk of uterine perfora-
tion or cervical laceration because it requires the physi-
cian to make fewer passes into the uterus with sharp
instruments and reduces the presence of sharp fetal
bone fragments that can injure the uterus and cervix.
There is also considerable evidence that D&X reduces
the risk of retained fetal tissue, a serious abortion com-
plication that can cause maternal death, and that D&X
reduces the incidence of a ‘free floating’ fetal head that
can be difficult for a physician to grasp and remove and
can thus cause maternal injury. That D&X procedures
usually take less time than other abortion methods used
at a comparable stage of pregnancy can also have health
advantages. The shorter the procedure, the less blood
loss, trauma, and exposure to anesthesia. The intuitive
safety advantages of intact D&E are supported by clini-
cal experience. Especially for women with particular
health conditions, there is medical evidence that D&X
may be safer than available alternatives.” Brief for
American College of Obstetricians and Gynecologists
et al. as Amici Curiae 21–22 (citation and footnotes
omitted).
4
The upshot is a District Court finding that D&X signifi-
cantly obviates health risks in certain circumstances, a
highly plausible record-based explanation of why that might
be so, a division of opinion among some medical experts over

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whether D&X is generally safer, and an absence of controlled
medical studies that would help answer these medical ques-
tions. Given these medically related evidentiary circum-
stances, we believe the law requires a health exception.
The word “necessary” in Casey’s phrase “necessary, in
appropriate medical judgment, for the preservation of the
life or health of the mother,” 505 U. S., at 879 (internal quota-
tion marks omitted), cannot refer to an absolute necessity or
to absolute proof. Medical treatments and procedures are
often considered appropriate (or inappropriate) in light of es-
timated comparative health risks (and health benefits) in par-
ticular cases. Neither can that phrase require unanimity of
medical opinion. Doctors often differ in their estimation of
comparative health risks and appropriate treatment. And
Casey’s words “appropriate medical judgment” must embody
the judicial need to tolerate responsible differences of medi-
cal opinion—differences of a sort that the American Medical
Association and American College of Obstetricians and Gy-
necologists’ statements together indicate are present here.
For another thing, the division of medical opinion about
the matter at most means uncertainty, a factor that signals
the presence of risk, not its absence. That division here in-
volves highly qualified knowledgeable experts on both sides
of the issue. Where a significant body of medical opinion
believes a procedure may bring with it greater safety for
some patients and explains the medical reasons supporting
that view, we cannot say that the presence of a different
view by itself proves the contrary. Rather, the uncertainty
means a significant likelihood that those who believe that
D&X is a safer abortion method in certain circumstances
may turn out to be right. If so, then the absence of a health
exception will place women at an unnecessary risk of tragic
health consequences. If they are wrong, the exception will
simply turn out to have been unnecessary.
In sum, Nebraska has not convinced us that a health
exception is “never necessary to preserve the health of

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women.” Reply Brief for Petitioners 4. Rather, a statute
that altogether forbids D&X creates a significant health risk.
The statute consequently must contain a health exception.
This is not to say, as Justice Thomas and Justice Ken-
nedy claim, that a State is prohibited from proscribing an
abortion procedure whenever a particular physician deems
the procedure preferable. By no means must a State grant
physicians “unfettered discretion” in their selection of abor-
tion methods. Post, at 969 (Kennedy, J., dissenting). But
where substantial medical authority supports the proposition
that banning a particular abortion procedure could endanger
women’s health, Casey requires the statute to include a
health exception when the procedure is “ ‘necessary, in ap-
propriate medical judgment, for the preservation of the life
or health of the mother.’ ” 505 U. S., at 879. Requiring
such an exception in this case is no departure from Casey,
but simply a straightforward application of its holding.
B
The Eighth Circuit found the Nebraska statute unconstitu-
tional because, in Casey’s words, it has the “effect of placing
a substantial obstacle in the path of a woman seeking an
abortion of a nonviable fetus.” Id., at 877. It thereby
places an “undue burden” upon a woman’s right to terminate
her pregnancy before viability. Ibid. Nebraska does not
deny that the statute imposes an “undue burden” if it applies
to the more commonly used D&E procedure as well as to
D&X. And we agree with the Eighth Circuit that it does
so apply.
Our earlier discussion of the D&E procedure, supra, at
924–926, shows that it falls within the statutory prohibition.
The statute forbids “deliberately and intentionally delivering
into the vagina a living unborn child, or a substantial portion
thereof, for the purpose of performing a procedure that the
person performing such procedure knows will kill the unborn
child.” Neb. Rev. Stat. Ann. § 28–326(9) (Supp. 1999). We

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do not understand how one could distinguish, using this lan-
guage, between D&E (where a foot or arm is drawn through
the cervix) and D&X (where the body up to the head is
drawn through the cervix). Evidence before the trial court
makes clear that D&E will often involve a physician pulling
a “substantial portion” of a still living fetus, say, an arm or
leg, into the vagina prior to the death of the fetus. 11 F.
Supp. 2d, at 1128; id., at 1128–1130. Indeed D&E involves
dismemberment that commonly occurs only when the fetus
meets resistance that restricts the motion of the fetus: “The
dismemberment occurs between the traction of . . . [the] in-
strument and the counter-traction of the internal os of the
cervix.” Id., at 1128. And these events often do not occur
until after a portion of a living fetus has been pulled into the
vagina. Id., at 1104; see also Medical and Surgical Abortion
135 (“During the mid-second trimester, separation of the
fetal corpus may occur when the fetus is drawn into the
lower uterine segment, where compression and traction
against the endocervix facilitates disarticulation”).
Even if the statute’s basic aim is to ban D&X, its language
makes clear that it also covers a much broader category of
procedures. The language does not track the medical differ-
ences between D&E and D&X—though it would have been
a simple matter, for example, to provide an exception for the
performance of D&E and other abortion procedures. E. g.,
Kan. Stat. Ann. § 65–6721(b)(1) (Supp. 1999). Nor does the
statute anywhere suggest that its application turns on
whether a portion of the fetus’ body is drawn into the vagina
as part of a process to extract an intact fetus after collapsing
the head as opposed to a process that would dismember the
fetus. Thus, the dissenters’ argument that the law was gen-
erally intended to bar D&X can be both correct and irrele-
vant. The relevant question is not whether the legislature
wanted to ban D&X; it is whether the law was intended to
apply only to D&X. The plain language covers both proce-
dures. A rereading of this opinion, supra, at 924–929, as

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well as Justice Thomas’ dissent, post, at 984–987, will make
clear why we can find no difference, in terms of this statute,
between the D&X procedure as described and the D&E pro-
cedure as it might be performed. (In particular, compare
post, at 984–986 (Thomas, J., dissenting), with post, at 986–
989 (Thomas, J., dissenting).) Both procedures can involve
the introduction of a “substantial portion” of a still living
fetus, through the cervix, into the vagina—the very feature
of an abortion that leads Justice Thomas to characterize
such a procedure as involving “partial birth.”
The Nebraska State Attorney General argues that the
statute does differentiate between the two procedures. He
says that the statutory words “substantial portion” mean
“the child up to the head.” He consequently denies the stat-
ute’s application where the physician introduces into the
birth canal a fetal arm or leg or anything less than the entire
fetal body. Brief for Petitioners 20. He argues further
that we must defer to his views about the meaning of the
state statute. Id., at 12–13.
We cannot accept the Attorney General’s narrowing in-
terpretation of the Nebraska statute. This Court’s case
law makes clear that we are not to give the Attorney
General’s interpretative views controlling weight. For one
thing, this Court normally follows lower federal-court in-
terpretations of state law. McMillian v. Monroe County,
520 U. S. 781, 786 (1997); Brockett v. Spokane Arcades,
Inc., 472 U. S. 491, 500, n. 9 (1985). It “rarely reviews a
construction of state law agreed upon by the two lower
federal courts.” Virginia v. American Booksellers Assn.,
Inc., 484 U. S. 383, 395 (1988). In this case, the two lower
courts have both rejected the Attorney General’s narrow-
ing interpretation.
For another, our precedent warns against accepting as
“authoritative” an Attorney General’s interpretation of
state law when “the Attorney General does not bind the
state courts or local law enforcement authorities.” Ibid.

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Opinion of the Court
Under Nebraska law, the Attorney General’s interpreta-
tive views do not bind the state courts. State v. Coff-
man, 213 Neb. 560, 561, 330 N. W. 2d 727, 728 (1983)
(Attorney General’s issued opinions, while entitled to “sub-
stantial weight” and “to be respectfully considered,” are
of “no controlling authority”). Nor apparently do they
bind elected county attorneys, to whom Nebraska gives
an independent authority to initiate criminal prosecutions.
Neb. Rev. Stat. Ann. §§ 23–1201(1), 28–328(5), 84–205(3)
(Supp. 1999); cf. Crandon v. United States, 494 U. S. 152,
177 (1990) (Scalia, J., concurring in judgment) (“[W]e
have never thought that the interpretation of those
charged with prosecuting criminal statutes is entitled to
deference”).
Nor can we say that the lower courts used the wrong
legal standard in assessing the Attorney General’s inter-
pretation. The Eighth Circuit recognized its “duty to give
[the law] a construction . . . that would avoid constitutional
doubts.” 192 F. 3d, at 1150. It nonetheless concluded
that the Attorney General’s interpretation would “twist
the words of the law and give them a meaning they cannot
reasonably bear.” Ibid. The Eighth Circuit is far from
alone in rejecting such a narrowing interpretation. The
language in question is based on model statutory language
(though some States omit any further definition of “partial
birth abortion”), which 10 lower federal courts have consid-
ered on the merits. All 10 of those courts (including the
Eighth Circuit) have found the language potentially appli-
cable to other abortion procedures. See Planned Parent-
hood of Greater Iowa, Inc. v. Miller, 195 F. 3d 386 (CA8
1999); Little Rock Family Planning Services v. Jegley, 192
F. 3d 794, 797–798 (CA8 1999); Hope Clinic, 195 F. 3d,
at 865–871 (imposing precautionary injunction to prevent
application beyond D&X); id., at 885–889 (Posner, C. J.,
dissenting); Rhode Island Medical Soc., 66 F. Supp. 2d,
at 309–310; Richmond Medical Center for Women, 55

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942 STENBERG v. CARHART
Opinion of the Court
F. Supp. 2d, at 471; A Choice for Women, 54 F. Supp. 2d, at
1155; Causeway Medical Suite, 43 F. Supp. 2d, at 614–615;
Planned Parenthood of Central N. J. v. Verniero, 41 F.
Supp. 2d 478, 503–504 (NJ 1998); Eubanks v. Stengel, 28
F. Supp. 2d 1024, 1034–1035 (WD Ky. 1998); Planned Par-
enthood of Southern Ariz., Inc. v. Woods, 982 F. Supp. 2d
1369, 1378 (Ariz. 1997); Kelley, 977 F. Supp. 2d, at 1317;
but cf. Richmond Medical Center v. Gilmore, 144 F. 3d
326, 330–332 (CA4 1998) (Luttig, J., granting stay).
Regardless, even were we to grant the Attorney Gener-
al’s views “substantial weight,” we still have to reject his
interpretation, for it conflicts with the statutory language
discussed supra, at 940. The Attorney General, echoed by
the dissents, tries to overcome that language by relying
on other language in the statute; in particular, the words
“partial birth abortion,” a term ordinarily associated with
the D&X procedure, and the words “partially delivers vagi-
nally a living unborn child.” Neb. Rev. Stat. Ann. § 28–
326(9) (Supp. 1999). But these words cannot help the At-
torney General. They are subject to the statute’s further
explicit statutory definition, specifying that both terms
include “delivering into the vagina a living unborn child,
or a substantial portion thereof.” Ibid. When a statute
includes an explicit definition, we must follow that defini-
tion, even if it varies from that term’s ordinary meaning.
Meese v. Keene, 481 U. S. 465, 484–485 (1987) (“It is axio-
matic that the statutory definition of the term excludes
unstated meanings of that term”); Colautti v. Franklin,
439 U. S., at 392–393, n. 10 (“As a rule, ‘a definition which
declares what a term “means” . . . excludes any meaning
that is not stated’ ”); Western Union Telegraph Co. v. Len-
root, 323 U. S. 490, 502 (1945); Fox v. Standard Oil Co. of
N. J., 294 U. S. 87, 95–96 (1935) (Cardozo, J.); see also 2A N.
Singer, Sutherland on Statutes and Statutory Construction
§ 47.07, p. 152, and n. 10 (5th ed. 1992) (collecting cases).
That is to say, the statute, read “as a whole,” post, at 998

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943 Cite as: 530 U. S. 914 (2000)
Opinion of the Court
(Thomas, J., dissenting), leads the reader to a definition.
That definition does not include the Attorney General’s
restriction—“the child up to the head.” Its words, “sub-
stantial portion,” indicate the contrary.
The Attorney General also points to the Nebraska Legis-
lature’s debates, where the term “partial birth abortion”
appeared frequently. But those debates hurt his argument
more than they help it. Nebraska’s legislators focused di-
rectly upon the meaning of the word “substantial.” One
senator asked the bill’s sponsor, “[Y]ou said that as small
a portion of the fetus as a foot would constitute a sub-
stantial portion in your opinion. Is that correct?” The
sponsoring senator replied, “Yes, I believe that’s cor-
rect.” App. 452–453; see also id., at 442–443 (same sen-
ator explaining “substantial” would “indicate that more
than a little bit has been delivered into the vagina,” i. e.,
“[e]nough that would allow for the procedure to end up
with the killing of the unborn child”); id., at 404 (rejecting
amendment to limit law to D&X). The legislature seems
to have wanted to avoid more limiting language lest it
become too easy to evade the statute’s strictures—a motive
that Justice Thomas well explains. Post, at 1001–1003.
That goal, however, exacerbates the problem.
The Attorney General, again echoed by the dissents,
further argues that the statute “distinguishes between the
overall ‘abortion procedure’ itself and the separate ‘proce-
dure’ used to kill the unborn child.” Brief for Petitioners
16–18; post, at 991–992 (opinion of Thomas, J.), 975–976
(opinion of Kennedy, J.). Even assuming that the dis-
tinction would help the Attorney General make the D&E/
D&X distinction he seeks, however, we cannot find any
language in the statute that supports it. He wants us
to read “procedure” in the statute’s last sentence to mean
“separate procedure,” i. e., the killing of the fetus, as op-
posed to a whole procedure, i. e., a D&E or D&X abortion.
But the critical word “separate” is missing. And the same

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944 STENBERG v. CARHART
Opinion of the Court
word “procedure,” in the same subsection and through-
out the statute, is used to refer to an entire abortion pro-
cedure. Neb. Rev. Stat. Ann. §§ 28–326(9), 28–328(1)–(4)
(Supp. 1999); cf. Gustafson v. Alloyd Co., 513 U. S. 561,
570 (1995) (“[I]dentical words used in different parts of
the same act are intended to have the same meaning”
(internal quotation marks omitted)).
The dissenters add that the statutory words “partially
delivers” can be read to exclude D&E. Post, at 990–991
(opinion of Thomas, J.), 974 (opinion of Kennedy, J.).
They say that introduction of, say, a limb or both limbs
into the vagina does not involve “delivery.” But obstetric
textbooks and even dictionaries routinely use that term to
describe any facilitated removal of tissue from the uterus,
not only the removal of an intact fetus. E. g., Obstetrics:
Normal & Problem Pregnancies, at 388 (describing “deliv-
ery” of fetal membranes, placenta, and umbilical cord in
the third stage of labor); B. Maloy, Medical Dictionary for
Lawyers 221 (3d ed. 1960) (“Also, the removal of a [fetal]
part such as the placenta”); 4 Oxford English Dictionary
422 (2d ed. 1989) (to “deliver” means, inter alia, to “dis-
burden (a women) of the foetus”); Webster’s Third New
International Dictionary (1993) (“[D]elivery” means “the
expulsion or extraction of a fetus and its membranes”).
In any event, the statute itself specifies that it applies
both to delivering “an intact unborn child” or “a substan-
tial portion thereof.” The dissents cannot explain how
introduction of a substantial portion of a fetus into the
vagina pursuant to D&X is a “delivery,” while introduction
pursuant to D&E is not.
We are aware that adopting the Attorney General’s inter-
pretation might avoid the constitutional problem discussed
in this section. But we are “without power to adopt a nar-
rowing construction of a state statute unless such a construc-
tion is reasonable and readily apparent.” Boos v. Barry, 485
U. S. 312, 330 (1988); Gooding v. Wilson, 405 U. S. 518, 520–

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945 Cite as: 530 U. S. 914 (2000)
Opinion of the Court
521 (1972). For the reasons stated, it is not reasonable to
replace the term “substantial portion” with the Attorney
General’s phrase “body up to the head.” See Almendarez-
Torres v. United States, 523 U. S. 224, 237–239 (1998) (statute
must be “genuinely susceptible” to two interpretations).
Finally, the law does not require us to certify the state-law
question to the Nebraska Supreme Court. Of course, we
lack any authoritative state-court construction. But “we
have never held that a federal litigant must await a state-
court construction or the development of an established prac-
tice before bringing the federal suit.” City of Lakewood v.
Plain Dealer Publishing Co., 486 U. S. 750, 770, n. 11 (1988).
The Attorney General did not seek a narrowing interpreta-
tion from the Nebraska Supreme Court nor did he ask the
federal courts to certify the interpretive question. See
Brief for State Appellants in Nos. 98–3245 and 98–3300
(CA8); cf. Arizonans for Official English v. Arizona, 520
U. S. 43 (1997). Even if we were inclined to certify the ques-
tion now, we cannot do so. Certification of a question (or
abstention) is appropriate only where the statute is “fairly
susceptible” to a narrowing construction, see Houston v.
Hill, 482 U. S. 451, 468–471 (1987). We believe it is not.
Moreover, the Nebraska Supreme Court grants certification
only if the certified question is “determinative of the cause.”
Neb. Rev. Stat. § 24–219 (1995); see also Houston v. Hill,
supra, at 471 (“It would be manifestly inappropriate to cer-
tify a question in a case where . . . there is no uncertain
question of state law whose resolution might affect the pend-
ing federal claim”). Here, it would not be determinative, in
light of the discussion in Part II–A, supra.
In sum, using this law some present prosecutors and fu-
ture Attorneys General may choose to pursue physicians who
use D&E procedures, the most commonly used method for
performing previability second trimester abortions. All
those who perform abortion procedures using that method
must fear prosecution, conviction, and imprisonment. The

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946 STENBERG v. CARHART
Stevens, J., concurring
result is an undue burden upon a woman’s right to make an
abortion decision. We must consequently find the statute
unconstitutional.
The judgment of the Court of Appeals is
Affirmed.
Justice Stevens, with whom Justice Ginsburg joins,
concurring.
Although much ink is spilled today describing the grue-
some nature of late-term abortion procedures, that rhetoric
does not provide me a reason to believe that the procedure
Nebraska here claims it seeks to ban is more brutal, more
gruesome, or less respectful of “potential life” than the
equally gruesome procedure Nebraska claims it still allows.
Justice Ginsburg and Judge Posner have, I believe, cor-
rectly diagnosed the underlying reason for the enactment of
this legislation—a reason that also explains much of the
Court’s rhetoric directed at an objective that extends well
beyond the narrow issue that this case presents. The rheto-
ric is almost, but not quite, loud enough to obscure the quiet
fact that during the past 27 years, the central holding of Roe
v. Wade, 410 U. S. 113 (1973), has been endorsed by all but 4
of the 17 Justices who have addressed the issue. That hold-
ing—that the word “liberty” in the Fourteenth Amendment
includes a woman’s right to make this difficult and extremely
personal decision—makes it impossible for me to understand
how a State has any legitimate interest in requiring a doctor
to follow any procedure other than the one that he or she
reasonably believes will best protect the woman in her exer-
cise of this constitutional liberty. But one need not even
approach this view today to conclude that Nebraska’s law
must fall. For the notion that either of these two equally
gruesome procedures performed at this late stage of gesta-
tion is more akin to infanticide than the other, or that the
State furthers any legitimate interest by banning one but

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947 Cite as: 530 U. S. 914 (2000)
O’Connor, J., concurring
not the other, is simply irrational. See U. S. Const., Amdt.
14.
Justice O’Connor, concurring.
The issue of abortion is one of the most contentious and
controversial in contemporary American society. It pre-
sents extraordinarily difficult questions that, as the Court
recognizes, involve “virtually irreconcilable points of view.”
Ante, at 921. The specific question we face today is whether
Nebraska’s attempt to proscribe a particular method of abor-
tion, commonly known as “partial birth abortion,” is con-
stitutional. For the reasons stated in the Court’s opinion,
I agree that Nebraska’s statute cannot be reconciled with
our decision in Planned Parenthood of Southeastern Pa. v.
Casey, 505 U. S. 833 (1992), and is therefore unconstitutional.
I write separately to emphasize the following points.
First, the Nebraska statute is inconsistent with Casey be-
cause it lacks an exception for those instances when the
banned procedure is necessary to preserve the health of the
mother. See id., at 879 (plurality opinion). Importantly,
Nebraska’s own statutory scheme underscores this constitu-
tional infirmity. As we held in Casey, prior to viability “the
woman has a right to choose to terminate her pregnancy.”
Id., at 870. After the fetus has become viable, States may
substantially regulate and even proscribe abortion, but any
such regulation or proscription must contain an exception
for instances “ ‘where it is necessary, in appropriate medical
judgment, for the preservation of the life or health of the
mother.’ ” Id., at 879 (quoting Roe v. Wade, 410 U. S. 113,
165 (1973)). Nebraska has recognized this constitutional
limitation in its separate statute generally proscribing
postviability abortions. See Neb. Rev. Stat. Ann. § 28–329
(Supp. 1999). That statute provides that “[n]o abortion shall
be performed after the time at which, in the sound medical
judgment of the attending physician, the unborn child clearly
appears to have reached viability, except when necessary to

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948 STENBERG v. CARHART
O’Connor, J., concurring
preserve the life or health of the mother.” Ibid. (emphasis
added). Because even a postviability proscription of abor-
tion would be invalid absent a health exception, Nebraska’s
ban on previability partial birth abortions, under the circum-
stances presented here, must include a health exception
as well, since the State’s interest in regulating abortions be-
fore viability is “considerably weaker” than after viability.
Ante, at 930. The statute at issue here, however, only ex-
cepts those procedures “necessary to save the life of the
mother whose life is endangered by a physical disorder,
physical illness, or physical injury.” Neb. Rev. Stat. Ann.
§ 28–328(1) (Supp. 1999). This lack of a health exception
necessarily renders the statute unconstitutional.
Contrary to the assertions of Justice Kennedy and Jus-
tice Thomas, the need for a health exception does not arise
from “the individual views of Dr. Carhart and his support-
ers.” Post, at 969 (Kennedy, J., dissenting); see also post,
at 1012–1013 (Thomas, J., dissenting). Rather, as the ma-
jority explains, where, as here, “a significant body of medical
opinion believes a procedure may bring with it greater safety
for some patients and explains the medical reasons support-
ing that view,” ante, at 937, then Nebraska cannot say that
the procedure will not, in some circumstances, be “necessary
to preserve the life or health of the mother.” Accordingly,
our precedent requires that the statute include a health
exception.
Second, Nebraska’s statute is unconstitutional on the alter-
native and independent ground that it imposes an undue bur-
den on a woman’s right to choose to terminate her pregnancy
before viability. Nebraska’s ban covers not just the dilation
and extraction (D&X) procedure, but also the dilation and
evacuation (D&E) procedure, “the most commonly used
method for performing previability second trimester abor-
tions.” Ante, at 945. The statute defines the banned
procedure as “deliberately and intentionally delivering into
the vagina a living unborn child, or a substantial portion

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949 Cite as: 530 U. S. 914 (2000)
O’Connor, J., concurring
thereof, for the purpose of performing a procedure that the
person performing such procedure knows will kill the unborn
child and does kill the unborn child.” Neb. Rev. Stat. Ann.
§ 28–326(9) (Supp. 1999) (emphasis added). As the Court ex-
plains, the medical evidence establishes that the D&E proce-
dure is included in this definition. Thus, it is not possible to
interpret the statute’s language as applying only to the D&X
procedure. Moreover, it is significant that both the District
Court and the Court of Appeals interpreted the statute as
prohibiting abortions performed using the D&E method as
well as the D&X method. See 192 F. 3d 1142, 1150 (CA8
1999); 11 F. Supp. 2d 1099, 1127–1131 (Neb. 1998). We have
stated on several occasions that we ordinarily defer to the
construction of a state statute given it by the lower federal
courts unless such a construction amounts to plain error.
See, e. g., Bishop v. Wood, 426 U. S. 341, 346 (1976) (“[T]his
Court has accepted the interpretation of state law in which
the District Court and the Court of Appeals have concurred
even if an examination of the state-law issue without such
guidance might have justified a different conclusion”); The
Tungus v. Skovgaard, 358 U. S. 588, 596 (1959). Such defer-
ence is not unique to the abortion context, but applies gener-
ally to state statutes addressing all areas of the law. See,
e. g., UNUM Life Ins. Co. of America v. Ward, 526 U. S. 358,
368 (1999) (“notice-prejudice” rule in state insurance law);
Brockett v. Spokane Arcades, Inc., 472 U. S. 491, 499 (1985)
(moral nuisance law); Runyon v. McCrary, 427 U. S. 160, 181
(1976) (statute of limitations for personal injury actions);
Bishop v. Wood, supra, at 346, n. 10 (city employment ordi-
nance). Given this construction, the statute is impermissi-
ble. Indeed, Nebraska conceded at oral argument that “the
State could not prohibit the D&E procedure.” Tr. of Oral
Arg. 10. By proscribing the most commonly used method
for previability second trimester abortions, see ante, at 924,
the statute creates a “substantial obstacle to a woman seek-
ing an abortion,” Casey, supra, at 884, and therefore imposes

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950 STENBERG v. CARHART
O’Connor, J., concurring
an undue burden on a woman’s right to terminate her preg-
nancy prior to viability.
It is important to note that, unlike Nebraska, some other
States have enacted statutes more narrowly tailored to pro-
scribing the D&X procedure alone. Some of those statutes
have done so by specifically excluding from their coverage
the most common methods of abortion, such as the D&E and
vacuum aspiration procedures. For example, the Kansas
statute states that its ban does not apply to the “(A) [s]uction
curettage abortion procedure; (B) suction aspiration abortion
procedure; or (C) dilation and evacuation abortion procedure
involving dismemberment of the fetus prior to removal from
the body of the pregnant woman.” Kan. Stat. Ann. § 65–
6721(b)(2) (Supp. 1998). The Utah statute similarly pro-
vides that its prohibition “does not include the dilation and
evacuation procedure involving dismemberment prior to re-
moval, the suction curettage procedure, or the suction aspi-
ration procedure for abortion.” Utah Code Ann. § 76–7–
310.5(1)(a) (1999). Likewise, the Montana statute defines
the banned procedure as one in which “(A) the living fetus
is removed intact from the uterus until only the head re-
mains in the uterus; (B) all or a part of the intracranial con-
tents of the fetus are evacuated; (C) the head of the fetus
is compressed; and (D) following fetal demise, the fetus is
removed from the birth canal.” Mont. Code Ann. § 50–20–
401(3)(c)(ii) (Supp. 1999). By restricting their prohibitions
to the D&X procedure exclusively, the Kansas, Utah, and
Montana statutes avoid a principal defect of the Nebraska
law.
If Nebraska’s statute limited its application to the D&X
procedure and included an exception for the life and health
of the mother, the question presented would be quite differ-
ent from the one we face today. As we held in Casey, an
abortion regulation constitutes an undue burden if it “has
the purpose or effect of placing a substantial obstacle in the
path of a woman seeking an abortion of a nonviable fetus.”

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951 Cite as: 530 U. S. 914 (2000)
Ginsburg, J., concurring
505 U. S., at 877. If there were adequate alternative meth-
ods for a woman safely to obtain an abortion before viability,
it is unlikely that prohibiting the D&X procedure alone
would “amount in practical terms to a substantial obstacle to
a woman seeking an abortion.” Id., at 884. Thus, a ban on
partial birth abortion that only proscribed the D&X method
of abortion and that included an exception to preserve the
life and health of the mother would be constitutional in my
view.
Nebraska’s statute, however, does not meet these criteria.
It contains no exception for when the procedure, in appro-
priate medical judgment, is necessary to preserve the health
of the mother; and it proscribes not only the D&X procedure
but also the D&E procedure, the most commonly used
method for previability second trimester abortions, thus
making it an undue burden on a woman’s right to terminate
her pregnancy. For these reasons, I agree with the Court
that Nebraska’s law is unconstitutional.
Justice Ginsburg, with whom Justice Stevens joins,
concurring.
I write separately only to stress that amidst all the emo-
tional uproar caused by an abortion case, we should not lose
sight of the character of Nebraska’s “partial birth abortion”
law. As the Court observes, this law does not save any
fetus from destruction, for it targets only “a method of
performing abortion.” Ante, at 930. Nor does the statute
seek to protect the lives or health of pregnant women.
Moreover, as Justice Stevens points out, ante, at 946 (con-
curring opinion), the most common method of performing
previability second trimester abortions is no less distressing
or susceptible to gruesome description. Seventh Circuit
Chief Judge Posner correspondingly observed, regarding
similar bans in Wisconsin and Illinois, that the law prohibits
the D&X procedure “not because the procedure kills the
fetus, not because it risks worse complications for the woman

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952 STENBERG v. CARHART
Rehnquist, C. J., dissenting
than alternative procedures would do, not because it is a
crueler or more painful or more disgusting method of termi-
nating a pregnancy.” Hope Clinic v. Ryan, 195 F. 3d 857,
881 (CA7 1999) (dissenting opinion). Rather, Chief Judge
Posner commented, the law prohibits the procedure because
the state legislators seek to chip away at the private choice
shielded by Roe v. Wade, 410 U. S. 113 (1973), even as modi-
fied by Planned Parenthood of Southeastern Pa. v. Casey,
505 U. S. 833 (1992). 195 F. 3d, at 880–882.
A state regulation that “has the purpose or effect of plac-
ing a substantial obstacle in the path of a woman seeking
an abortion of a nonviable fetus” violates the Constitution.
Casey, 505 U. S., at 877 (plurality opinion). Such an obstacle
exists if the State stops a woman from choosing the proce-
dure her doctor “reasonably believes will best protect the
woman in [the] exercise of [her] constitutional liberty.”
Ante, at 946 (Stevens, J., concurring); see Casey, 505 U. S.,
at 877 (“means chosen by the State to further the interest in
potential life must be calculated to inform the woman’s free
choice, not hinder it”). Again as stated by Chief Judge
Posner, “if a statute burdens constitutional rights and all
that can be said on its behalf is that it is the vehicle that
legislators have chosen for expressing their hostility to those
rights, the burden is undue.” Hope Clinic, 195 F. 3d, at
881.
Chief Justice Rehnquist, dissenting.
I did not join the joint opinion in Planned Parenthood of
Southeastern Pa. v. Casey, 505 U. S. 833 (1992), and continue
to believe that case is wrongly decided. Despite my dis-
agreement with the opinion, under the rule laid down in
Marks v. United States, 430 U. S. 188, 193 (1977), the Casey
joint opinion represents the holding of the Court in that case.
I believe Justice Kennedy and Justice Thomas have cor-
rectly applied Casey’s principles and join their dissenting
opinions.

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953 Cite as: 530 U. S. 914 (2000)
Scalia, J., dissenting
Justice Scalia, dissenting.
I am optimistic enough to believe that, one day, Stenberg
v. Carhart will be assigned its rightful place in the history
of this Court’s jurisprudence beside Korematsu and Dred
Scott. The method of killing a human child—one cannot
even accurately say an entirely unborn human child—pro-
scribed by this statute is so horrible that the most clinical
description of it evokes a shudder of revulsion. And the
Court must know (as most state legislatures banning this
procedure have concluded) that demanding a “health excep-
tion”—which requires the abortionist to assure himself that,
in his expert medical judgment, this method is, in the case
at hand, marginally safer than others (how can one prove the
contrary beyond a reasonable doubt?)—is to give live-birth
abortion free rein. The notion that the Constitution of the
United States, designed, among other things, “to establish
Justice, insure domestic Tranquility, . . . and secure the
Blessings of Liberty to ourselves and our Posterity,” prohib-
its the States from simply banning this visibly brutal means
of eliminating our half-born posterity is quite simply absurd.
Even so, I had not intended to write separately here until
the focus of the other separate writings (including the one I
have joined) gave me cause to fear that this case might be
taken to stand for an error different from the one that it
actually exemplifies. Because of the Court’s practice of pub-
lishing dissents in the order of the seniority of their authors,
this writing will appear in the United States Reports before
those others, but the reader will not comprehend what fol-
lows unless he reads them first.
* * *
The two lengthy dissents in this case have, appropriately
enough, set out to establish that today’s result does not fol-
low from this Court’s most recent pronouncement on the
matter of abortion, Planned Parenthood of Southeastern Pa.
v. Casey, 505 U. S. 833 (1992). It would be unfortunate, how-

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Scalia, J., dissenting
ever, if those who disagree with the result were induced to
regard it as merely a regrettable misapplication of Casey.
It is not that, but is Casey’s logical and entirely predictable
consequence. To be sure, the Court’s construction of this
statute so as to make it include procedures other than live-
birth abortion involves not only a disregard of fair meaning,
but an abandonment of the principle that even ambiguous
statutes should be interpreted in such fashion as to render
them valid rather than void. Casey does not permit that
jurisprudential novelty—which must be chalked up to the
Court’s inclination to bend the rules when any effort to limit
abortion, or even to speak in opposition to abortion, is at
issue. It is of a piece, in other words, with Hill v. Colorado,
ante, p. 703, also decided today.
But the Court gives a second and independent reason for
invalidating this humane (not to say antibarbarian) law: That
it fails to allow an exception for the situation in which the
abortionist believes that this live-birth method of destroying
the child might be safer for the woman. (As pointed out by
Justice Thomas, and elaborated upon by Justice Ken-
nedy, there is no good reason to believe this is ever the case,
but—who knows?—it sometime might be.)
I have joined Justice Thomas’s dissent because I agree
that today’s decision is an “unprecedented expansio[n]” of
our prior cases, post, at 1012, “is not mandated” by Casey’s
“undue-burden” test, post, at 1010, and can even be called
(though this pushes me to the limit of my belief) “obviously
irreconcilable with Casey’s explication of what its undue-
burden standard requires,” post, at 983. But I never put
much stock in Casey’s explication of the inexplicable. In the
last analysis, my judgment that Casey does not support to-
day’s tragic result can be traced to the fact that what I con-
sider to be an “undue burden” is different from what the
majority considers to be an “undue burden”—a conclusion
that cannot be demonstrated true or false by factual inquiry
or legal reasoning. It is a value judgment, dependent upon
how much one respects (or believes society ought to respect)

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Scalia, J., dissenting
the life of a partially delivered fetus, and how much one re-
spects (or believes society ought to respect) the freedom of
the woman who gave it life to kill it. Evidently, the five
Justices in today’s majority value the former less, or the lat-
ter more, (or both), than the four of us in dissent. Case
closed. There is no cause for anyone who believes in Casey
to feel betrayed by this outcome. It has been arrived at by
precisely the process Casey promised—a democratic vote by
nine lawyers, not on the question whether the text of the
Constitution has anything to say about this subject (it obvi-
ously does not); nor even on the question (also appropriate
for lawyers) whether the legal traditions of the American
people would have sustained such a limitation upon abortion
(they obviously would); but upon the pure policy question
whether this limitation upon abortion is “undue”—i. e., goes
too far.
In my dissent in Casey, I wrote that the “undue burden”
test made law by the joint opinion created a standard that
was “as doubtful in application as it is unprincipled in ori-
gin,” Casey, 505 U. S., at 985; “hopelessly unworkable in
practice,” id., at 986; “ultimately standardless,” id., at 987.
Today’s decision is the proof. As long as we are debating
this issue of necessity for a health-of-the-mother exception
on the basis of Casey, it is really quite impossible for us dis-
senters to contend that the majority is wrong on the law—
any more than it could be said that one is wrong in law to
support or oppose the death penalty, or to support or oppose
mandatory minimum sentences. The most that we can hon-
estly say is that we disagree with the majority on their
policy-judgment-couched-as-law. And those who believe
that a 5-to-4 vote on a policy matter by unelected lawyers
should not overcome the judgment of 30 state legislatures
have a problem, not with the application of Casey, but with
its existence. Casey must be overruled.
While I am in an I-told-you-so mood, I must recall my be-
musement, in Casey, at the majority opinion’s expressed be-

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Kennedy, J., dissenting
lief that Roe v. Wade, 410 U. S. 133 (1973), had “call[ed] the
contending sides of a national controversy to end their na-
tional division by accepting a common mandate rooted in the
Constitution,” Casey, 505 U. S., at 867, and that the decision
in Casey would ratify that happy truce. It seemed to me,
quite to the contrary, that “Roe fanned into life an issue that
has inflamed our national politics in general, and has ob-
scured with its smoke the selection of Justices to this Court
in particular, ever since”; and that, “by keeping us in the
abortion-umpiring business, it is the perpetuation of that dis-
ruption, rather than of any Pax Roeana, that the Court’s
new majority decrees.” Id., at 995–996. Today’s decision,
that the Constitution of the United States prevents the pro-
hibition of a horrible mode of abortion, will be greeted by a
firestorm of criticism—as well it should. I cannot under-
stand why those who acknowledge that, in the opening words
of Justice O’Connor’s concurrence, “[t]he issue of abortion
is one of the most contentious and controversial in contempo-
rary American society,” ante, at 947, persist in the belief that
this Court, armed with neither constitutional text nor ac-
cepted tradition, can resolve that contention and controversy
rather than be consumed by it. If only for the sake of its
own preservation, the Court should return this matter to the
people—where the Constitution, by its silence on the subject,
left it—and let them decide, State by State, whether this
practice should be allowed. Casey must be overruled.
Justice Kennedy, with whom The Chief Justice
joins, dissenting.
For close to two decades after Roe v. Wade, 410 U. S. 113
(1973), the Court gave but slight weight to the interests of
the separate States when their legislatures sought to address
persisting concerns raised by the existence of a woman’s
right to elect an abortion in defined circumstances. When
the Court reaffirmed the essential holding of Roe, a central
premise was that the States retain a critical and legitimate

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Kennedy, J., dissenting
role in legislating on the subject of abortion, as limited by
the woman’s right the Court restated and again guaranteed.
Planned Parenthood of Southeastern Pa. v. Casey, 505 U. S.
833 (1992). The political processes of the State are not to
be foreclosed from enacting laws to promote the life of the
unborn and to ensure respect for all human life and its poten-
tial. Id., at 871 (plurality opinion). The State’s constitu-
tional authority is a vital means for citizens to address these
grave and serious issues, as they must if we are to progress
in knowledge and understanding and in the attainment of
some degree of consensus.
The Court’s decision today, in my submission, repudiates
this understanding by invalidating a statute advancing criti-
cal state interests, even though the law denies no woman the
right to choose an abortion and places no undue burden upon
the right. The legislation is well within the State’s compe-
tence to enact. Having concluded Nebraska’s law survives
the scrutiny dictated by a proper understanding of Casey,
I dissent from the judgment invalidating it.
I
The Court’s failure to accord any weight to Nebraska’s in-
terest in prohibiting partial birth abortion is erroneous and
undermines its discussion and holding. The Court’s ap-
proach in this regard is revealed by its description of the
abortion methods at issue, which the Court is correct to de-
scribe as “clinically cold or callous.” Ante, at 923. The ma-
jority views the procedures from the perspective of the abor-
tionist, rather than from the perspective of a society shocked
when confronted with a new method of ending human life.
Words invoked by the majority, such as “transcervical proce-
dures,” “[o]smotic dilators,” “instrumental disarticulation,”
and “paracervical block,” may be accurate and are to some
extent necessary, ante, at 924–925; but for citizens who seek
to know why laws on this subject have been enacted across
the Nation, the words are insufficient. Repeated references

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Kennedy, J., dissenting
to sources understandable only to a trained physician may
obscure matters for persons not trained in medical terminol-
ogy. Thus it seems necessary at the outset to set forth what
may happen during an abortion.
The person challenging Nebraska’s law is Dr. Leroy Car-
hart, a physician who received his medical degree from
Hahnemann Hospital and University in 1973. App. 29.
Dr. Carhart performs the procedures in a clinic in Nebraska,
id., at 30, and will also travel to Ohio to perform abortions
there, id., at 86. Dr. Carhart has no specialty certifications
in a field related to childbirth or abortion and lacks admitting
privileges at any hospital. Id., at 82, 83. He performs
abortions throughout pregnancy, including when he is unsure
whether the fetus is viable. Id., at 116. In contrast to the
physicians who provided expert testimony in this case (who
are board certified instructors at leading medical education
institutions and members of the American Board of Obstetri-
cians and Gynecologists), Dr. Carhart performs the partial
birth abortion procedure (D&X) that Nebraska seeks to ban.
He also performs the other method of abortion at issue in
the case, the D&E.
As described by Dr. Carhart, the D&E procedure requires
the abortionist to use instruments to grasp a portion (such
as a foot or hand) of a developed and living fetus and drag
the grasped portion out of the uterus into the vagina. Id.,
at 61. Dr. Carhart uses the traction created by the opening
between the uterus and vagina to dismember the fetus, tear-
ing the grasped portion away from the remainder of the
body. Ibid. The traction between the uterus and vagina is
essential to the procedure because attempting to abort a
fetus without using that traction is described by Dr. Carhart
as “pulling the cat’s tail” or “drag[ging] a string across the
floor, you’ll just keep dragging it. It’s not until something
grabs the other end that you are going to develop traction.”
Id., at 62. The fetus, in many cases, dies just as a human
adult or child would: It bleeds to death as it is torn limb from

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Kennedy, J., dissenting
limb. Id., at 63. The fetus can be alive at the beginning of
the dismemberment process and can survive for a time while
its limbs are being torn off. Dr. Carhart agreed that
“[w]hen you pull out a piece of the fetus, let’s say, an arm or
a leg and remove that, at the time just prior to removal of
the portion of the fetus, . . . the fetus [is] alive.” Id., at 62.
Dr. Carhart has observed fetal heartbeat via ultrasound with
“extensive parts of the fetus removed,” id., at 64, and testi-
fied that mere dismemberment of a limb does not always
cause death because he knows of a physician who removed
the arm of a fetus only to have the fetus go on to be born
“as a living child with one arm.” Id., at 63. At the con-
clusion of a D&E abortion no intact fetus remains. In
Dr. Carhart’s words, the abortionist is left with “a tray full
of pieces.” Id., at 125.
The other procedure implicated today is called “partial
birth abortion” or the D&X. The D&X can be used, as a
general matter, after 19 weeks’ gestation because the fetus
has become so developed that it may survive intact partial
delivery from the uterus into the vagina. Id., at 61. In the
D&X, the abortionist initiates the woman’s natural delivery
process by causing the cervix of the woman to be dilated,
sometimes over a sequence of days. Id., at 492. The fetus’
arms and legs are delivered outside the uterus while the
fetus is alive; witnesses to the procedure report seeing the
body of the fetus moving outside the woman’s body. Brief
for Petitioners 4. At this point, the abortion procedure has
the appearance of a live birth. As stated by one group of
physicians, “[a]s the physician manually performs breech ex-
traction of the body of a live fetus, excepting the head, she
continues in the apparent role of an obstetrician delivering
a child.” Brief for Association of American Physicians and
Surgeons et al. as Amici Curiae 27. With only the head of
the fetus remaining in utero, the abortionist tears open the
skull. According to Dr. Martin Haskell, a leading proponent
of the procedure, the appropriate instrument to be used at

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960 STENBERG v. CARHART
Kennedy, J., dissenting
this stage of the abortion is a pair of scissors. M. Haskell,
Dilation and Extraction for Late Second Trimester Abortion
(1992), in 139 Cong. Rec. 8605 (1993). Witnesses report ob-
serving the portion of the fetus outside the woman react to
the skull penetration. Brief for Petitioners 4. The abor-
tionist then inserts a suction tube and vacuums out the
developing brain and other matter found within the skull.
The process of making the size of the fetus’ head smaller
is given the clinically neutral term “reduction procedure.”
11 F. Supp. 2d 1099, 1106 (Neb. 1998). Brain death does
not occur until after the skull invasion, and, according to
Dr. Carhart, the heart of the fetus may continue to beat for
minutes after the contents of the skull are vacuumed out.
App. 58. The abortionist next completes the delivery of a
dead fetus, intact except for the damage to the head and the
missing contents of the skull.
Of the two described procedures, Nebraska seeks only to
ban the D&X. In light of the description of the D&X proce-
dure, it should go without saying that Nebraska’s ban on
partial birth abortion furthers purposes States are entitled
to pursue. Dr. Carhart nevertheless maintains the State
has no legitimate interest in forbidding the D&X. As he
interprets the controlling cases in this Court, the only two
interests the State may advance through regulation of abor-
tion are in the health of the woman who is considering the
procedure and in the life of the fetus she carries. Brief for
Respondent 45. The Court, as I read its opinion, accedes to
his views, misunderstanding Casey and the authorities it
confirmed.
Casey held that cases decided in the wake of Roe v. Wade,
410 U. S. 113 (1973), had “given [state interests] too little
acknowledgment and implementation.” 505 U. S., at 871
(plurality opinion). The decision turned aside any conten-
tion that a person has the “right to decide whether to have
an abortion without ‘interference from the State,’ ” id., at
875, and rejected a strict scrutiny standard of review as “in-

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Kennedy, J., dissenting
compatible with the recognition that there is a substantial
state interest in potential life throughout pregnancy.” Id.,
at 876. “The very notion that the State has a substantial
interest in potential life leads to the conclusion that not all
regulations must be deemed unwarranted.” Ibid. We held
it was inappropriate for the Judicial Branch to provide an
exhaustive list of state interests implicated by abortion.
Id., at 877.
Casey is premised on the States having an important con-
stitutional role in defining their interests in the abortion de-
bate. It is only with this principle in mind that Nebraska’s
interests can be given proper weight. The State’s brief de-
scribes its interests as including concern for the life of the
unborn and “for the partially-born,” in preserving the integ-
rity of the medical profession, and in “erecting a barrier
to infanticide.” Brief for Petitioners 48–49. A review of
Casey demonstrates the legitimacy of these policies. The
Court should say so.
States may take sides in the abortion debate and come
down on the side of life, even life in the unborn:
“Even in the earliest stages of pregnancy, the State may
enact rules and regulations designed to encourage [a
woman] to know that there are philosophic and social
arguments of great weight that can be brought to bear
in favor of continuing the pregnancy to full term and
that there are procedures and institutions to allow adop-
tion of unwanted children as well as a certain degree of
state assistance if the mother chooses to raise the child
herself.” 505 U. S., at 872 (plurality opinion).
States also have an interest in forbidding medical proce-
dures which, in the State’s reasonable determination, might
cause the medical profession or society as a whole to become
insensitive, even disdainful, to life, including life in the
human fetus. Abortion, Casey held, has consequences be-
yond the woman and her fetus. The States’ interests in reg-

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962 STENBERG v. CARHART
Kennedy, J., dissenting
ulating are of concomitant extension. Casey recognized that
abortion is “fraught with consequences for . . . the persons
who perform and assist in the procedure [and for] society
which must confront the knowledge that these procedures
exist, procedures some deem nothing short of an act of vio-
lence against innocent human life.” Id., at 852 (majority
opinion).
A State may take measures to ensure the medical profes-
sion and its members are viewed as healers, sustained by
a compassionate and rigorous ethic and cognizant of the
dignity and value of human life, even life which cannot sur-
vive without the assistance of others. Ibid.; Washington v.
Glucksberg, 521 U. S. 702, 730–734 (1997).
Casey demonstrates that the interests asserted by the
State are legitimate and recognized by law. It is argued,
however, that a ban on the D&X does not further these inter-
ests. This is because, the reasoning continues, the D&E
method, which Nebraska claims to be beyond its intent to
regulate, can still be used to abort a fetus and is no less
dehumanizing than the D&X method. While not adopting
the argument in express terms, the Court indicates tacit ap-
proval of it by refusing to reject it in a forthright manner.
Rendering express what is only implicit in the majority opin-
ion, Justice Stevens and Justice Ginsburg are forth-
right in declaring that the two procedures are indistinguish-
able and that Nebraska has acted both irrationally and
without a proper purpose in enacting the law. The issue is
not whether members of the judiciary can see a difference
between the two procedures. It is whether Nebraska can.
The Court’s refusal to recognize Nebraska’s right to declare
a moral difference between the procedures is a dispiriting
disclosure of the illogic and illegitimacy of the Court’s ap-
proach to the entire case.
Nebraska was entitled to find the existence of a consequen-
tial moral difference between the procedures. We are re-
ferred to substantial medical authority that D&X perverts

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Kennedy, J., dissenting
the natural birth process to a greater degree than D&E, com-
mandeering the live birth process until the skull is pierced.
American Medical Association (AMA) publications describe
the D&X abortion method as “ethically wrong.” AMA
Board of Trustees Factsheet on HR 1122 (June 1997), in
App. to Brief for Association of American Physicians and
Surgeons et al. as Amici Curiae 1 (AMA Factsheet). The
D&X differs from the D&E because in the D&X the fetus is
“killed outside of the womb” where the fetus has “an auton-
omy which separates it from the right of the woman to
choose treatments for her own body.” Ibid.; see also App.
639–640; Brief for Association of American Physicians and
Surgeons et al. as Amici Curiae 27 (“Intact D&X is aberrant
and troubling because the technique confuses the disparate
role of a physician in childbirth and abortion in such a way
as to blur the medical, legal, and ethical line between infanti-
cide and abortion”). Witnesses to the procedure relate that
the fingers and feet of the fetus are moving prior to the
piercing of the skull; when the scissors are inserted in the
back of the head, the fetus’ body, wholly outside the woman’s
body and alive, reacts as though startled and goes limp.
D&X’s stronger resemblance to infanticide means Nebraska
could conclude the procedure presents a greater risk of disre-
spect for life and a consequent greater risk to the profession
and society, which depend for their sustenance upon recipro-
cal recognition of dignity and respect. The Court is without
authority to second-guess this conclusion.
Those who oppose abortion would agree, indeed would in-
sist, that both procedures are subject to the most severe
moral condemnation, condemnation reserved for the most re-
pulsive human conduct. This is not inconsistent, however,
with the further proposition that as an ethical and moral
matter D&X is distinct from D&E and is a more serious con-
cern for medical ethics and the morality of the larger society
the medical profession must serve. Nebraska must obey the
legal regime which has declared the right of the woman to

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964 STENBERG v. CARHART
Kennedy, J., dissenting
have an abortion before viability. Yet it retains its power
to adopt regulations which do not impose an undue burden
on the woman’s right. By its regulation, Nebraska instructs
all participants in the abortion process, including the mother,
of its moral judgment that all life, including the life of the
unborn, is to be respected. The participants, Nebraska has
determined, cannot be indifferent to the procedure used and
must refrain from using the natural delivery process to kill
the fetus. The differentiation between the procedures is it-
self a moral statement, serving to promote respect for human
life; and if the woman and her physician in contemplating the
moral consequences of the prohibited procedure conclude
that grave moral consequences pertain to the permitted
abortion process as well, the choice to elect or not to elect
abortion is more informed; and the policy of promoting re-
spect for life is advanced.
It ill-serves the Court, its institutional position, and the
constitutional sources it seeks to invoke to refuse to issue a
forthright affirmation of Nebraska’s right to declare that
critical moral differences exist between the two procedures.
The natural birth process has been appropriated; yet the
Court refuses to hear the State’s voice in defining its inter-
ests in its law. The Court’s holding contradicts Casey’s as-
surance that the State’s constitutional position in the realm
of promoting respect for life is more than marginal.
II
Demonstrating a further and basic misunderstanding of
Casey, the Court holds the ban on the D&X procedure fails
because it does not include an exception permitting an abor-
tionist to perform a D&X whenever he believes it will best
preserve the health of the woman. Casting aside the views
of distinguished physicians and the statements of leading
medical organizations, the Court awards each physician a
veto power over the State’s judgment that the procedures
should not be performed. Dr. Carhart has made the medical

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Kennedy, J., dissenting
judgment to use the D&X procedure in every case, regard-
less of indications, after 15 weeks’ gestation. 11 F. Supp.
2d, at 1105. Requiring Nebraska to defer to Dr. Carhart’s
judgment is no different from forbidding Nebraska from
enacting a ban at all; for it is now Dr. Leroy Carhart who
sets abortion policy for the State of Nebraska, not the legis-
lature or the people. Casey does not give precedence to the
views of a single physician or a group of physicians regarding
the relative safety of a particular procedure.
I am in full agreement with Justice Thomas that the ap-
propriate Casey inquiry is not, as the Court would have it,
whether the State is preventing an abortionist from doing
something that, in his medical judgment, he believes to be
the most appropriate course of treatment. Post, at 1009–
1013. Casey addressed the question “whether the State can
resolve . . . philosophic questions [about abortion] in such a
definitive way that a woman lacks all choice in the matter.”
505 U. S., at 850. We decided the issue against the State,
holding that a woman cannot be deprived of the opportunity
to make reproductive decisions. Id., at 860. Casey made it
quite evident, however, that the State has substantial con-
cerns for childbirth and the life of the unborn and may enact
laws “which in no real sense depriv[e] women of the ultimate
decision.” Id., at 875 (plurality opinion). Laws having the
“purpose or effect of placing a substantial obstacle in the
path of a woman seeking an abortion of a nonviable fetus”
are prohibited. Id., at 877. Nebraska’s law does not have
this purpose or effect.
The holding of Casey, allowing a woman to elect abortion
in defined circumstances, is not in question here. Nebraska,
however, was entitled to conclude that its ban, while advanc-
ing important interests regarding the sanctity of life, de-
prived no woman of a safe abortion and therefore did not
impose a substantial obstacle on the rights of any woman.
The American College of Obstetricians and Gynecologists
(ACOG) “could identify no circumstances under which [D&X]

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966 STENBERG v. CARHART
Kennedy, J., dissenting
would be the only option to save the life or preserve the
health of the woman.” App. 600–601. The AMA agrees,
stating the “AMA’s expert panel, which included an ACOG
representative, could not find ‘any’ identified circumstance
where it was ‘the only appropriate alternative.’ ” AMA
Factsheet 1. The Court’s conclusion that the D&X is the
safest method requires it to replace the words “may be” with
the word “is” in the following sentence from ACOG’s position
statement: “An intact D&X, however, may be the best or
most appropriate procedure in a particular circumstance.”
App. 600–601.
No studies support the contention that the D&X abortion
method is safer than other abortion methods. Brief for Re-
spondent 36, n. 41. Leading proponents of the procedure
acknowledge that the D&X has “disadvantages” versus other
methods because it requires a high degree of surgical skill
to pierce the skull with a sharp instrument in a blind proce-
dure. Haskell, 139 Cong. Rec. 8605 (1993). Other doctors
point to complications that may arise from the D&X. Brief
for American Physicians and Surgeons et al. as Amici Cu-
riae 21–23; App. 186. A leading physician, Frank Boehm,
M. D., who has performed and supervised abortions as direc-
tor of the Fetal Intensive Care Unit and the Maternal/Fetal
Medicine Division at Vanderbilt University Hospital, has re-
fused to support use of the D&X, both because no medical
need for the procedure exists and because of ethical con-
cerns. Id., at 636, 639–640, 656–657. Dr. Boehm, a fellow
of ACOG, id., at 565, supports abortion rights and has pro-
vided sworn testimony in opposition to previous state at-
tempts to regulate abortion. Id., at 608–614.
The Court cannot conclude the D&X is part of standard
medical practice. It is telling that no expert called by
Dr. Carhart, and no expert testifying in favor of the pro-
cedure, had in fact performed a partial birth abortion in his
or her medical practice. E. g., id., at 308 (testimony of
Dr. Phillip Stubblefield). In this respect their opinions were

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Kennedy, J., dissenting
courtroom conversions of uncertain reliability. Litigation in
other jurisdictions establishes that physicians do not adopt
the D&X procedure as part of standard medical practice.
E. g., Richmond Medical Center for Women v. Gilmore, 144
F. 3d 326, 328 (CA4 1998); Hope Clinic v. Ryan, 195 F. 3d 857,
871 (CA7 1999); see also App. 603–604. It is quite wrong for
the Court to conclude, as it seems to have done here, that
Dr. Carhart conforms his practice to the proper standard of
care because he has incorporated the procedure into his prac-
tice. Neither Dr. Boehm nor Dr. Carhart’s lead expert,
Dr. Stubblefield (the chairman of the Department of Obstet-
rics and Gynecology at Boston University School of Medicine
and director of obstetrics and gynecology for the Boston
Medical Center), has done so.
Substantial evidence supports Nebraska’s conclusion that
its law denies no woman a safe abortion. The most to be
said for the D&X is it may present an unquantified lower
risk of complication for a particular patient but that other
proven safe procedures remain available even for this pa-
tient. Under these circumstances, the Court is wrong to
limit its inquiry to the relative physical safety of the two
procedures, with the slightest potential difference requiring
the invalidation of the law. As Justice O’Connor ex-
plained in an earlier case, the State may regulate based on
matters beyond “what various medical organizations have to
say about the physical safety of a particular procedure.”
Akron v. Akron Center for Reproductive Health, Inc., 462
U. S. 416, 467 (1983) (dissenting opinion). Where the differ-
ence in physical safety is, at best, marginal, the State may
take into account the grave moral issues presented by a new
abortion method. See Casey, 505 U. S., at 880 (requiring a
regulation to impose a “significant threat to the life or health
of a woman” before its application would impose an undue
burden (internal quotation marks omitted)). Dr. Carhart
does not decide to use the D&X based on a conclusion that
it is best for a particular woman. Unsubstantiated and gen-

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968 STENBERG v. CARHART
Kennedy, J., dissenting
eralized health differences which are, at best, marginal, do
not amount to a substantial obstacle to the abortion right.
Id., at 874, 876 (plurality opinion). It is also important to
recognize that the D&X is effective only when the fetus is
close to viable or, in fact, viable; thus the State is regulating
the process at the point where its interest in life is nearing
its peak.
Courts are ill-equipped to evaluate the relative worth of
particular surgical procedures. The legislatures of the sev-
eral States have superior factfinding capabilities in this re-
gard. In an earlier case, Justice O’Connor had explained
that the general rule extends to abortion cases, writing that
the Court is not suited to be “the Nation’s ex officio medical
board with powers to approve or disapprove medical and
operative practices and standards throughout the United
States.” 462 U. S., at 456 (dissenting opinion) (internal quo-
tation marks omitted). “Irrespective of the difficulty of the
task, legislatures, with their superior factfinding capabilities,
are certainly better able to make the necessary judgments
than are courts.” Id., at 456, n. 4. Nebraska’s judgment
here must stand.
In deferring to the physician’s judgment, the Court turns
back to cases decided in the wake of Roe, cases which gave
a physician’s treatment decisions controlling weight. Before
it was repudiated by Casey, the approach of deferring to phy-
sicians had reached its apex in Akron, supra, where the
Court held an informed consent requirement was unconstitu-
tional. The law challenged in Akron required the abortion-
ist to inform the woman of the status of her pregnancy, the
development of her fetus, the date of possible viability, the
physical and emotional complications that may result from
an abortion, and the availability of agencies to provide assist-
ance and information. Id., at 442. The physician was also
required to advise the woman of the risks associated with
the abortion technique to be employed and other informa-
tion. Ibid. The law was invalidated based on the physi-

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969 Cite as: 530 U. S. 914 (2000)
Kennedy, J., dissenting
cian’s right to practice medicine in the way he or she saw fit;
for, according to the Akron Court, “[i]t remains primarily
the responsibility of the physician to ensure that appropriate
information is conveyed to his patient, depending on her
particular circumstances.” Id., at 443. Dispositive for the
Court was that the law was an “intrusion upon the discretion
of the pregnant woman’s physician.” Id., at 445. The phy-
sician was placed in an “undesired and uncomfortable strait-
jacket.” Ibid. (internal quotation marks omitted). The
Court’s decision today echoes the Akron Court’s deference
to a physician’s right to practice medicine in the way he or
she sees fit.
The Court, of course, does not wish to cite Akron; yet the
Court’s holding is indistinguishable from the reasoning in
Akron that Casey repudiated. No doubt exists that today’s
holding is based on a physician-first view which finds its
primary support in that now-discredited case. Rather than
exalting the right of a physician to practice medicine with
unfettered discretion, Casey recognized: “Whatever constitu-
tional status the doctor-patient relation may have as a gen-
eral matter, in the present context it is derivative of the
woman’s position.” 505 U. S., at 884 ( joint opinion of O’Con-
nor, Kennedy, and Souter, JJ.). Casey discussed the in-
formed consent requirement struck down in Akron and held
Akron was wrong. The doctor-patient relation was only
“entitled to the same solicitude it receives in other contexts.”
505 U. S., at 884. The standard of medical practice cannot
depend on the individual views of Dr. Carhart and his sup-
porters. The question here is whether there was substan-
tial and objective medical evidence to demonstrate the State
had considerable support for its conclusion that the ban cre-
ated a substantial risk to no woman’s health. Casey recog-
nized the point, holding the physician’s ability to practice
medicine was “subject to reasonable . . . regulation by the
State” and would receive the “same solicitude it receives in
other contexts.” Ibid. In other contexts, the State is enti-

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Kennedy, J., dissenting
tled to make judgments where high medical authority is in
disagreement.
The Court fails to acknowledge substantial authority
allowing the State to take sides in a medical debate, even
when fundamental liberty interests are at stake and even
when leading members of the profession disagree with the
conclusions drawn by the legislature. In Kansas v. Hen-
dricks, 521 U. S. 346 (1997), we held that disagreements
among medical professionals “do not tie the State’s hands in
setting the bounds of . . . laws. In fact, it is precisely where
such disagreement exists that legislatures have been af-
forded the widest latitude.” Id., at 360, n. 3. Instead,
courts must exercise caution (rather than require deference
to the physician’s treatment decision) when medical uncer-
tainty is present. Ibid. (“[W]hen a legislature ‘undertakes
to act in areas fraught with medical and scientific uncertain-
ties, legislative options must be especially broad and courts
should be cautious not to rewrite legislation’ ”) (quoting
Jones v. United States, 463 U. S. 354, 370 (1983)); see also
Collins v. Texas, 223 U. S. 288, 297–298 (1912) (Holmes, J.)
(declaring the “right of the state to adopt a policy even upon
medical matters concerning which there is difference of opin-
ion and dispute”); Lambert v. Yellowley, 272 U. S. 581, 596–
597 (1926) (rejecting claim of distinguished physician because
“[h]igh medical authority being in conflict . . . , it would,
indeed, be strange if Congress lacked the power [to act]”);
Marshall v. United States, 414 U. S. 417, 427 (1974) (recog-
nizing “there is no agreement among members of the medi-
cal profession” (internal quotation marks omitted)); United
States v. Rutherford, 442 U. S. 544 (1979) (discussing regula-
tory approval process for certain drugs).
Instructive is Jacobson v. Massachusetts, 197 U. S. 11
(1905), where the defendant was convicted because he re-
fused to undergo a smallpox vaccination. The defendant
claimed the mandatory vaccination violated his liberty to
“care for his own body and health in such way as to him

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971 Cite as: 530 U. S. 914 (2000)
Kennedy, J., dissenting
seems best.” Id., at 26. He offered to prove that members
of the medical profession took the position that the vaccina-
tion was of no value and, in fact, was harmful. Id., at 30.
The Court rejected the claim, establishing beyond doubt the
right of the legislature to resolve matters upon which physi-
cians disagreed:
“Those offers [of proof by the defendant] in the main
seem to have had no purpose except to state the general
theory of those of the medical profession who attach lit-
tle or no value to vaccination as a means of preventing
the spread of smallpox, or who think that vaccination
causes other diseases of the body. What everybody
knows the court must know, and therefore the state
court judicially knew, as this court knows, that an oppo-
site theory accords with the common belief, and is main-
tained by high medical authority. We must assume
that, when the statute in question was passed, the legis-
lature of Massachusetts was not unaware of these oppos-
ing theories, and was compelled, of necessity, to choose
between them. It was not compelled to commit a mat-
ter involving the public health and safety to the final
decision of a court or jury. It is no part of the function
of a court or a jury to determine which one of two modes
was likely to be the most effective for the protection of
the public against disease. That was for the legislative
department to determine in the light of all the informa-
tion it had or could obtain. It could not properly abdi-
cate its function to guard the public health and safety.”
Ibid.
The Jacobson Court quoted with approval a recent state-
court decision which observed, in words having full applica-
tion today:
“The fact that the belief is not universal [in the medical
community] is not controlling, for there is scarcely any
belief that is accepted by everyone. The possibility that

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972 STENBERG v. CARHART
Kennedy, J., dissenting
the belief may be wrong, and that science may yet show
it to be wrong, is not conclusive; for the legislature has
the right to pass laws which, according to common belief
of the people, are adapted to [address medical matters].
In a free country, where government is by the people,
through their chosen representatives, practical legisla-
tion admits of no other standard of action.’ ” Id., at 35
(quoting Viemester v. White, 179 N. Y. 235, 241, 72 N. E.
97, 99 (1904)).
Justice O’Connor assures the people of Nebraska they
are free to redraft the law to include an exception permitting
the D&X to be performed when “the procedure, in appro-
priate medical judgment, is necessary to preserve the health
of the mother.” Ante, at 951. The assurance is meaning-
less. She has joined an opinion which accepts that Dr. Car-
hart exercises “appropriate medical judgment” in using the
D&X for every patient in every procedure, regardless of indi-
cations, after 15 weeks’ gestation. Ante, at 937 (requiring
any health exception to “tolerate responsible differences of
medical opinion” which “are present here”). A ban which
depends on the “appropriate medical judgment” of Dr. Car-
hart is no ban at all. He will be unaffected by any new
legislation. This, of course, is the vice of a health exception
resting in the physician’s discretion.
In light of divided medical opinion on the propriety of the
partial birth abortion technique (both in terms of physical
safety and ethical practice) and the vital interests asserted
by Nebraska in its law, one is left to ask what the first Justice
Harlan asked: “Upon what sound principles as to the rela-
tions existing between the different departments of govern-
ment can the court review this action of the legislature?”
Jacobson, supra, at 31. The answer is none.
III
The Court’s next holding is that Nebraska’s ban forbids
both the D&X procedure and the more common D&E proce-

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973 Cite as: 530 U. S. 914 (2000)
Kennedy, J., dissenting
dure. In so ruling the Court misapplies settled doctrines of
statutory construction and contradicts Casey’s premise that
the States have a vital constitutional position in the abortion
debate. I agree with the careful statutory analysis con-
ducted by Justice Thomas, post, at 989–1005. Like the
ruling requiring a physician veto, requiring a State to meet
unattainable standards of statutory draftsmanship in order
to have its voice heard on this grave and difficult subject is
no different from foreclosing state participation altogether.
Nebraska’s statute provides:
“No partial birth abortion shall be performed in this
state unless such procedure is necessary to save the life
of the mother whose life is endangered by a physical
disorder, physical illness, or physical injury, including
a life-endangering physical condition caused by or aris-
ing from the pregnancy itself.” Neb. Rev. Stat. Ann.
§ 28–328(1) (Supp. 1999).
The statute defines “partial birth abortion” as
“an abortion procedure in which the person performing
the abortion partially delivers vaginally a living unborn
child before killing the unborn child and completing the
delivery.” § 28–326(9).
It further defines “partially delivers vaginally a living un-
born child before killing the unborn child” to mean
“deliberately and intentionally delivering into the va-
gina a living unborn child, or a substantial portion
thereof, for the purpose of performing a procedure that
the person performing such procedure knows will kill
the unborn child and does kill the unborn child.” Ibid.
The text demonstrates the law applies only to the D&X pro-
cedure. Nebraska’s intention is demonstrated at three
points in the statutory language: references to “partial-birth
abortion” and to the “delivery” of a fetus; and the require-

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974 STENBERG v. CARHART
Kennedy, J., dissenting
ment that the delivery occur “before” the performance of the
death-causing procedure.
The term “partial birth abortion” means an abortion per-
formed using the D&X method as described above. The
Court of Appeals acknowledged the term “is commonly un-
derstood to refer to a particular procedure known as in-
tact dilation and extraction (D&X).” Little Rock Family
Planning Servs. v. Jegley, 192 F. 3d 794, 795 (CA8 1999).
Dr. Carhart’s own lead expert, Dr. Phillip Stubblefield, pref-
aced his description of the D&X procedure by describing it
as the procedure “which, in the lay press, has been called a
partial-birth abortion.” App. 271–272. And the AMA has
declared: “The ‘partial birth abortion’ legislation is by its
very name aimed exclusively [at the D&X.] There is no
other abortion procedure which could be confused with that
description.” AMA Factsheet 3. A commonsense under-
standing of the statute’s reference to “partial-birth abortion”
demonstrates its intended reach and provides all citizens the
fair warning required by the law. McBoyle v. United
States, 283 U. S. 25, 27 (1931).
The statute’s intended scope is demonstrated by its re-
quirement that the banned procedure include a partial “de-
livery” of the fetus into the vagina and the completion of a
“delivery” at the end of the procedure. Only removal of an
intact fetus can be described as a “delivery” of a fetus and
only the D&X involves an intact fetus. In a D&E, portions
of the fetus are pulled into the vagina with the intention of
dismembering the fetus by using the traction at the opening
between the uterus and vagina. This cannot be considered
a delivery of a portion of a fetus. In Dr. Carhart’s own
words, the D&E leaves the abortionist with a “tray full of
pieces,” App. 125, at the end of the procedure. Even if it
could be argued, as the majority does, ante, at 944, that
dragging a portion of an intact fetus into the vagina as the
first step of a D&E is a delivery of that portion of an intact
fetus, the D&E still does not involve “completing the deliv-

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975 Cite as: 530 U. S. 914 (2000)
Kennedy, J., dissenting
ery” of an intact fetus. Whatever the statutory term “com-
pleting the delivery” of an unborn child means, it cannot
mean, as the Court would have it, placing fetal remains on a
tray. See Planned Parenthood of Wis. v. Doyle, 9 F. Supp.
2d 1033, 1041 (WD Wis. 1998) (the statute is “readily applied
to the partial delivery of an intact child but hardly applicable
to the delivery of dismembered body parts”).
Medical descriptions of the abortion procedures confirm
the point, for it is only the description of the D&X that in-
vokes the word “delivery.” App. 600. The United States,
as amicus, cannot bring itself to describe the D&E as involv-
ing a “delivery,” instead substituting the word “emerges” to
describe how the fetus is brought into the vagina in a D&E.
Brief for United States as Amicus Curiae 10. The Court,
in a similar admission, uses the words “a physician pulling”
a portion of a fetus, ante, at 939, rather than a “physician
delivering” a portion of a fetus; yet only a procedure involv-
ing a delivery is banned by the law. Of all the definitions of
“delivery” provided by the Court, ante, at 944, not one
supports (or, more important for statutory construction pur-
poses, requires) the conclusion that the statutory term “com-
pleting the delivery” refers to the placement of dismembered
body parts on a tray rather than the removal of an intact
fetus from the woman’s body.
The operation of Nebraska’s law is further defined by the
requirement that the fetus be partially delivered into the
vagina “before” the abortionist kills it. The partial delivery
must be undertaken “for the purpose of performing a proce-
dure that the person . . . knows will kill the unborn child.”
Neb. Rev. Stat. Ann. § 28–326(9) (Supp. 1999). The law is
most naturally read to require the death of the fetus to take
place in two steps: First the fetus must be partially delivered
into the vagina and then the defendant must perform a
death-causing procedure. In a D&E, forcing the fetus into
the vagina (the pulling of extremities off the body in the
process of extracting the body parts from the uterus into the

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976 STENBERG v. CARHART
Kennedy, J., dissenting
vagina) is also the procedure that kills the fetus. Richmond
Medical Center for Women v. Gilmore, 144 F. 3d, at 330
(order of Luttig, J.). In a D&X, the fetus is partially deliv-
ered into the vagina before a separate procedure (the so-
called “reduction procedure”) is performed in order to kill
the fetus.
The majority rejects this argument based on its conclusion
that the word “procedure” must “refer to an entire abortion
procedure” each time it is used. Ante, at 944. This inter-
pretation makes no sense. It would require us to conclude
that the Nebraska Legislature considered the “entire abor-
tion procedure” to take place after the abortionist has al-
ready delivered into the vagina a living unborn child, or
a substantial portion thereof. Neb. Rev. Stat. Ann. § 28–
326(9) (Supp. 1999). All medical authorities agree, however,
that the entire abortion procedure begins several days be-
fore this stage, with the dilation of the cervix. The majority
asks us, in effect, to replace the words “for the purpose of
performing” with the words “in the course of performing” in
the portion of § 28–326(9) quoted in the preceding paragraph.
The reference to “procedure” refers to the separate death-
causing procedure that is unique to the D&X.
In light of the statutory text, the commonsense under-
standing must be that the statute covers only the D&X.
See Broadrick v. Oklahoma, 413 U. S. 601, 698 (1973). The
AMA does not disagree. It writes: “The partial birth abor-
tion legislation is by its very name aimed exclusively at a
procedure by which a living fetus is intentionally and delib-
erately given partial birth and delivered for the purpose of
killing it. There is no other abortion procedure which could
be confused with that description.” AMA Factsheet 3 (in-
ternal quotation marks omitted). Casey disavows strict
scrutiny review; and Nebraska must be afforded leeway
when attempting to regulate the medical profession. See
Kansas v. Hendricks, 521 U. S., at 359 (“[W]e have tradition-
ally left to legislators the task of defining terms of a medical

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977 Cite as: 530 U. S. 914 (2000)
Kennedy, J., dissenting
nature that have legal significance”). To hold the statute
covers the D&E, the Court must disagree with the AMA
and disregard the known intent of the legislature, adequately
expressed in the statute.
Strained statutory constructions in abortion cases are not
new, for Justice O’Connor identified years ago “an unprec-
edented canon of construction under which in cases involving
abortion, a permissible reading of a statute is to be avoided
at all costs.” Thornburgh v. American College of Obstetri-
cians and Gynecologists, 476 U. S. 747, 829 (1986) (dissenting
opinion) (internal quotation marks omitted). Casey ban-
ished this doctrine from our jurisprudence; yet the Court
today reinvigorates it and, in the process, ignores its obliga-
tion to interpret the law in a manner to validate it, not
render it void. E. g., Johnson v. Robison, 415 U. S. 361, 366–
367 (1974); Edward J. DeBartolo Corp. v. Florida Gulf Coast
Building & Constr. Trades Council, 485 U. S. 568, 575 (1988).
Avoidance of unconstitutional constructions is discussed only
in two sentences of the Court’s analysis and dismissed as
inapplicable because the statute is not susceptible to the con-
struction offered by the Nebraska Attorney General. Ante,
at 944–945. For the reasons here discussed, the statute is
susceptible to the construction; and the Court is required to
adopt it.
The Court and Justice O’Connor seek to shield them-
selves from criticism by citing the interpretations of the par-
tial birth abortion statutes offered by some other federal
courts. Ante, at 941–942. On this issue of nationwide im-
portance, these courts have no special competence; and of
appellate courts to consider similar statutes, a majority have,
in contrast to the Court, declared that the law could be inter-
preted to cover only the D&X. See Hope Clinic, 195 F. 3d,
at 865–871; Richmond Medical Center, supra, at 330–332
(order of Luttig, J.). Thirty States have enacted similar
laws. It is an abdication of responsibility for the Court to
suggest its hands are tied by decisions which paid scant at-

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978 STENBERG v. CARHART
Kennedy, J., dissenting
tention to Casey’s recognition of the State’s authority and
misapplied the doctrine of construing statutes to avoid con-
stitutional difficulty. Further, the leading case describing
the deference argument, Frisby v. Schultz, 487 U. S. 474, 483
(1988), declined to defer to a lower court construction of
the state statute at issue in the case. As Frisby observed,
the “lower courts ran afoul of the well-established principle
that statutes will be interpreted to avoid constitutional dif-
ficulties.” See also Webster v. Reproductive Health Serv-
ices, 492 U. S. 490, 514 (1989) (opinion of Rehnquist, C. J.);
id., at 525 (O’Connor, J., concurring in part and concurring
in judgment).
The majority and, even more so, the concurring opinion
by Justice O’Connor, ignore the settled rule against decid-
ing unnecessary constitutional questions. The State of Ne-
braska conceded, under its understanding of Casey, that if
this law must be interpreted to bar D&E as well as D&X it
is unconstitutional. Since the majority concludes this is in-
deed the case, that should have been the end of the matter.
Yet the Court and Justice O’Connor go much further.
They conclude that the statute requires a health exception
which, for all practical purposes and certainly in the circum-
stances of this case, allows the physician to make the deter-
mination in his own professional judgment. This is an im-
mense constitutional holding. It is unnecessary; and, for the
reasons I have sought to explain, it is incorrect. While it is
not clear which of the two halves of the majority opinion is
dictum, both are wrong.
The United States District Court in this case leaped to
prevent the law from being enforced, granting an injunction
before it was applied or interpreted by Nebraska. Cf. Hill
v. Colorado, ante, p. 703. In so doing, the court excluded
from the abortion debate not just the Nebraska legislative
branch but the State’s executive and judiciary as well. The
law was enjoined before the chief law enforcement officer

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979 Cite as: 530 U. S. 914 (2000)
Kennedy, J., dissenting
of the State, its Attorney General, had any opportunity to
interpret it. The federal court then ignored the representa-
tions made by that officer during this litigation. In like
manner, Nebraska’s courts will be given no opportunity to
define the contours of the law, although by all indications
those courts would give the statute a more narrow construc-
tion than the one so eagerly adopted by the Court today.
E. g., Stenberg v. Moore, 258 Neb. 199, 206, 602 N. W. 2d 465,
472 (1995). Thus the court denied each branch of Nebraska’s
government any role in the interpretation or enforcement of
the statute. This cannot be what Casey meant when it said
we would be more solicitous of state attempts to vindicate
interests related to abortion. Casey did not assume this
state of affairs.
IV
Ignoring substantial medical and ethical opinion, the
Court substitutes its own judgment for the judgment of Ne-
braska and some 30 other States and sweeps the law away.
The Court’s holding stems from misunderstanding the rec-
ord, misinterpretation of Casey, outright refusal to respect
the law of a State, and statutory construction in conflict with
settled rules. The decision nullifies a law expressing the
will of the people of Nebraska that medical procedures must
be governed by moral principles having their foundation in
the intrinsic value of human life, including the life of the
unborn. Through their law the people of Nebraska were
forthright in confronting an issue of immense moral conse-
quence. The State chose to forbid a procedure many decent
and civilized people find so abhorrent as to be among the
most serious of crimes against human life, while the State
still protected the woman’s autonomous right of choice as
reaffirmed in Casey. The Court closes its eyes to these pro-
found concerns.
From the decision, the reasoning, and the judgment,
I dissent.

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980 STENBERG v. CARHART
Thomas, J., dissenting
Justice Thomas, with whom The Chief Justice and
Justice Scalia join, dissenting.
In 1973, this Court struck down an Act of the Texas Legis-
lature that had been in effect since 1857, thereby rendering
unconstitutional abortion statutes in dozens of States. Roe
v. Wade, 410 U. S. 113, 119. As some of my colleagues on
the Court, past and present, ably demonstrated, that decision
was grievously wrong. See, e. g., Doe v. Bolton, 410 U. S.
179, 221–223 (1973) (White, J., dissenting); Roe v. Wade,
supra, at 171–178 (Rehnquist, J., dissenting). Abortion is
a unique act, in which a woman’s exercise of control over
her own body ends, depending on one’s view, human life or
potential human life. Nothing in our Federal Constitution
deprives the people of this country of the right to determine
whether the consequences of abortion to the fetus and to
society outweigh the burden of an unwanted pregnancy on
the mother. Although a State may permit abortion, nothing
in the Constitution dictates that a State must do so.
In the years following Roe, this Court applied, and, worse,
extended, that decision to strike down numerous state stat-
utes that purportedly threatened a woman’s ability to obtain
an abortion. The Court voided parental consent laws, see
Planned Parenthood of Central Mo. v. Danforth, 428 U. S.
52, 75 (1976), legislation requiring that second-trimester
abortions take place in hospitals, see Akron v. Akron Center
for Reproductive Health, Inc., 462 U. S. 416, 431 (1983), and
even a requirement that both parents of a minor be notified
before their child has an abortion, see Hodgson v. Minnesota,
497 U. S. 417, 455 (1990). It was only a slight exaggeration
when this Court described, in 1976, a right to abortion “with-
out interference from the State.” Danforth, supra, at 61.
The Court’s expansive application of Roe in this period, even
more than Roe itself, was fairly described as the “unre-
strained imposition of [the Court’s] own, extraconstitutional
value preferences” on the American people. Thornburgh v.

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981 Cite as: 530 U. S. 914 (2000)
Thomas, J., dissenting
American College of Obstetricians and Gynecologists, 476
U. S. 747, 794 (1986) (White, J., dissenting).
It appeared that this era of Court-mandated abortion on
demand had come to an end, first with our decision in Web-
ster v. Reproductive Health Services, 492 U. S. 490 (1989),
see id., at 557 (Blackmun, J., concurring in part and dissent-
ing in part) (lamenting that the plurality had “discard[ed]”
Roe), and then finally (or so we were told) in our decision in
Planned Parenthood of Southeastern Pa. v. Casey, 505 U. S.
833 (1992). Although in Casey the separate opinions of The
Chief Justice and Justice Scalia urging the Court to
overrule Roe did not command a majority, seven Members of
that Court, including six Members sitting today, acknowl-
edged that States have a legitimate role in regulating abor-
tion and recognized the States’ interest in respecting fetal
life at all stages of development. See 505 U. S., at 877 ( joint
opinion of O’Connor, Kennedy, and Souter, JJ.); id., at 944
(Rehnquist, C. J., joined by White, Scalia, and Thomas,
JJ., concurring in judgment in part and dissenting in part);
id., at 979 (Scalia, J., joined by Rehnquist, C. J., and White
and Thomas, JJ., concurring in judgment in part and dissent-
ing in part). The plurality authored by Justices O’Con-
nor, Kennedy, and Souter concluded that prior case law
“went too far” in “undervalu[ing] the State’s interest in po-
tential life” and in “striking down . . . some abortion regula-
tions which in no real sense deprived women of the ultimate
decision.” Id., at 875. 1 Roe and subsequent cases, accord-
ing to the plurality, had wrongly “treat[ed] all governmental
attempts to influence a woman’s decision on behalf of the
potential life within her as unwarranted,” a treatment that
was “incompatible with the recognition that there is a sub-
stantial state interest in potential life throughout preg-
nancy.” Id., at 876. Accordingly, the plurality held that so
1 Unless otherwise noted, all subsequent cites of Planned Parenthood of
Southeastern Pa. v. Casey, 505 U. S. 833 (1992), are to the joint opinion of
O’Connor, Kennedy, and Souter, JJ.

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982 STENBERG v. CARHART
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long as state regulation of abortion furthers legitimate inter-
ests—that is, interests not designed to strike at the right
itself—the regulation is invalid only if it imposes an undue
burden on a woman’s ability to obtain an abortion, meaning
that it places a substantial obstacle in the woman’s path.
Id., at 874, 877.
My views on the merits of the Casey plurality have been
fully articulated by others. Id., at 944 (Rehnquist, C. J.,
concurring in judgment in part and dissenting in part); id.,
at 979 (Scalia, J., concurring in judgment in part and dis-
senting in part). I will not restate those views here, except
to note that the Casey plurality opinion was constructed by
its authors out of whole cloth. The standard set forth in the
Casey plurality has no historical or doctrinal pedigree. The
standard is a product of its authors’ own philosophical views
about abortion, and it should go without saying that it has
no origins in or relationship to the Constitution and is, conse-
quently, as illegitimate as the standard it purported to re-
place. Even assuming, however, as I will for the remainder
of this dissent, that Casey’s fabricated undue-burden stand-
ard merits adherence (which it does not), today’s decision is
extraordinary. Today, the Court inexplicably holds that the
States cannot constitutionally prohibit a method of abortion
that millions find hard to distinguish from infanticide and
that the Court hesitates even to describe. Ante, at 923.
This holding cannot be reconciled with Casey’s undue-burden
standard, as that standard was explained to us by the au-
thors of the plurality opinion, and the majority hardly pre-
tends otherwise. In striking down this statute—which ex-
presses a profound and legitimate respect for fetal life and
which leaves unimpeded several other safe forms of abor-
tion—the majority opinion gives the lie to the promise of
Casey that regulations that do no more than “express pro-
found respect for the life of the unborn are permitted, if they
are not a substantial obstacle to the woman’s exercise of the
right to choose” whether or not to have an abortion. 505

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983 Cite as: 530 U. S. 914 (2000)
Thomas, J., dissenting
U. S., at 877. Today’s decision is so obviously irreconcilable
with Casey’s explication of what its undue-burden standard
requires, let alone the Constitution, that it should be seen
for what it is, a reinstitution of the pre-Webster abortion-on-
demand era in which the mere invocation of “abortion rights”
trumps any contrary societal interest. If this statute is un-
constitutional under Casey, then Casey meant nothing at all,
and the Court should candidly admit it.
To reach its decision, the majority must take a series of
indefensible steps. The majority must first disregard the
principles that this Court follows in every context but abor-
tion: We interpret statutes according to their plain meaning,
and we do not strike down statutes susceptible of a narrow-
ing construction. The majority also must disregard the
very constitutional standard it purports to employ, and then
displace the considered judgment of the people of Nebraska
and 29 other States. The majority’s decision is lamentable,
because of the result the majority reaches, the illogical steps
the majority takes to reach it, and because it portends a re-
turn to an era I had thought we had at last abandoned.
I
In the almost 30 years since Roe, this Court has never
described the various methods of aborting a second- or
third-trimester fetus. From reading the majority’s sani-
tized description, one would think that this case involves
state regulation of a widely accepted routine medical proce-
dure. Nothing could be further from the truth. The most
widely used method of abortion during this stage of preg-
nancy is so gruesome that its use can be traumatic even for
the physicians and medical staff who perform it. See App.
656 (testimony of Dr. Boehm); W. Hern, Abortion Practice
134 (1990). And the particular procedure at issue in this
case, “partial birth abortion,” so closely borders on infanti-
cide that 30 States have attempted to ban it. I will begin
with a discussion of the methods of abortion available to

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984 STENBERG v. CARHART
Thomas, J., dissenting
women late in their pregnancies before addressing the statu-
tory and constitutional questions involved.2
1. The primary form of abortion used at or after 16 weeks’
gestation is known as “dilation and evacuation” or “D&E.”
11 F. Supp. 2d 1099, 1103, 1129 (Neb. 1998). When per-
formed during that stage of pregnancy, the D&E procedure
requires the physician to dilate the woman’s cervix and then
extract the fetus from her uterus with forceps. Id., at 1103;
App. 490 (American Medical Association (AMA), Report of
the Board of Trustees on Late-Term Abortion). Because of
the fetus’ size at this stage, the physician generally removes
the fetus by dismembering the fetus one piece at a time.3
11 F. Supp. 2d, at 1103–1104. The doctor grabs a fetal
extremity, such as an arm or a leg, with forceps and “pulls
it through the cervical os . . . tearing . . . fetal parts from
the fetal body . . . by means of traction.” Id., at 1104. See
App. 55 (testimony of Dr. Carhart). In other words, the
physician will grasp the fetal parts and “basically tear off
pieces of the fetus and pull them out.” Id., at 267 (testimony
of Dr. Stubblefield). See also id., at 149 (testimony of
2 In 1996, the most recent year for which abortion statistics are available
from the Centers for Disease Control and Prevention, there were approxi-
mately 1,221,585 abortions performed in the United States. Centers for
Disease Control and Prevention, Abortion Surveillance—United States,
1996, p. 1 (July 30, 1999). Of these abortions, about 67,000—5.5%—were
performed in or after the 16th week of gestation, that is, from the middle
of the second trimester through the third trimester. Id., at 5. The ma-
jority apparently accepts that none of the abortion procedures used for
pregnancies in earlier stages of gestation, including “dilation and evacua-
tion” (D&E) as it is practiced between 13 and 15 weeks’ gestation, would
be compromised by the statute. See ante, at 938–940 (concluding that
the statute could be interpreted to apply to instrumental dismemberment
procedures used in a later term D&E). Therefore, only the methods of
abortion available to women in this later stage of pregnancy are at issue
in this case.
3 At 16 weeks’ gestation, the average fetus is approximately six inches
long. By 20 weeks’ gestation, the fetus is approximately eight inches
long. K. Moore & T. Persaud, The Developing Human 112 (6th ed. 1998).

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Thomas, J., dissenting
Dr. Hodgson) (“[Y]ou grasp the fetal parts, and you often
don’t know what they are, and you try to pull it down, and
its . . . simply all there is to it”). The fetus will die from
blood loss, either because the physician has separated the
umbilical cord prior to beginning the procedure or because
the fetus loses blood as its limbs are removed. Id., at 62–
64 (testimony of Dr. Carhart); id., at 151 (testimony of
Dr. Hodgson).4 When all of the fetus’ limbs have been re-
moved and only the head is left in utero, the physician will
then collapse the skull and pull it through the cervical canal.
Id., at 106 (testimony of Dr. Carhart); id., at 297 (testimony
of Dr. Stubblefield); Causeway Medical Suite v. Foster, 43
F. Supp. 2d 604, 608 (ED La. 1999). At the end of the proce-
dure, the physician is left, in respondent’s words, with a
“tray full of pieces.” App. 125 (testimony of Dr. Carhart).
2. Some abortions after the 15th week are performed
using a method of abortion known as induction. 11 F. Supp.
2d, at 1108; App. 492 (AMA, Report of the Board of Trustees
on Late-Term Abortion). In an induction procedure, the
amniotic sac is injected with an abortifacient such as a sa-
line solution or a solution that contains prostaglandin. 11
F. Supp. 2d, at 1108. Uterine contractions typically follow,
causing the fetus to be expelled. Ibid.
3. A third form of abortion for use during or after 16
weeks’ gestation is referred to by some medical professionals
as “intact D&E.” There are two variations of this method,
both of which require the physician to dilate the woman’s
cervix. Gynecologic, Obstetric, and Related Surgery 1043
(D. Nichols & D. Clarke-Pearson eds., 2d ed. 2000); App. 271
(testimony of Dr. Stubblefield). The first variation is used
only in vertex presentations, that is, when the fetal head is
presented first. To perform a vertex-presentation intact
D&E, the doctor will insert an instrument into the fetus’
4 Past the 20th week of gestation, respondent attempts to induce fetal
death by injection prior to beginning the procedure in patients. 11
F. Supp. 2d, at 1106; App. 64.

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skull while the fetus is still in utero and remove the brain
and other intracranial contents. 11 F. Supp. 2d, at 1111;
Gynecologic, Obstetric, and Related Surgery, supra, at 1043;
App. 271 (testimony of Dr. Stubblefield). When the fetal
skull collapses, the physician will remove the fetus.
The second variation of intact D&E is the procedure com-
monly known as “partial birth abortion.” 5 11 F. Supp. 2d,
at 1106; Gynecologic, Obstetric, and Related Surgery, supra,
at 1043; App. 271 (testimony of Dr. Stubblefield). This pro-
cedure, which is used only rarely, is performed on mid- to
late-second-trimester (and sometimes third-trimester) fe-
tuses.6 Although there are variations, it is generally per-
5 There is a disagreement among the parties regarding the appropriate
term for this procedure. Congress and numerous state legislatures, in-
cluding Nebraska’s, have described this procedure as “partial birth abor-
tion,” reflecting the fact that the fetus is all but born when the physician
causes its death. See infra this page and 987. Respondent prefers to
refer generically to “intact dilation and evacuation” or “intact D&E” with-
out reference to whether the fetus is presented head first or feet first.
One of the doctors who developed the procedure, Martin Haskell, de-
scribed it as “Dilation and Extraction” or “D&X.” See The Partial-Birth
Abortion Ban Act of 1995, Hearing on H. R. 1833 before the Senate Com-
mittee on the Judiciary, 104th Cong., 1st Sess., 5 (1995) (hereinafter H. R.
1833 Hearing). The Executive Board of the American College of Obste-
tricians and Gynecologists (ACOG) refers to the procedure by the hybrid
term “intact dilation and extraction” or “intact D&X,” see App. 599
(ACOG Executive Board, Statement on Intact Dilation and Extraction
(Jan. 12, 1997)), which term was adopted by the AMA, see id., at 492
(AMA, Report of the Board of Trustees on Late-Term Abortion). I will
use the term “partial birth abortion” to describe the procedure because it
is the legal term preferred by 28 state legislatures, including the State of
Nebraska, and by the United States Congress. As I will discuss, see
infra, at 999–1001, there is no justification for the majority’s preference
for the terms “breech-conversion intact D&E” and “D&X” other than the
desire to make this procedure appear to be medically sanctioned.
6 There is apparently no general understanding of which women are ap-
propriate candidates for the procedure. Respondent uses the procedure
on women at 16 to 20 weeks’ gestation. 11 F. Supp. 2d, at 1105. The
doctor who developed the procedure, Dr. Martin Haskell, indicated that he

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Thomas, J., dissenting
formed as follows: After dilating the cervix, the physician
will grab the fetus by its feet and pull the fetal body out of
the uterus into the vaginal cavity. 11 F. Supp. 2d, at 1106.
At this stage of development, the head is the largest part of
the body. Assuming the physician has performed the dila-
tion procedure correctly, the head will be held inside the
uterus by the woman’s cervix. Ibid.; H. R. 1833 Hearing 8.
While the fetus is stuck in this position, dangling partly out
of the woman’s body, and just a few inches from a completed
birth, the physician uses an instrument such as a pair of scis-
sors to tear or perforate the skull. 11 F. Supp. 2d, at 1106;
App. 664 (testimony of Dr. Boehm); Joint Hearing on S. 6 and
H. R. 929 before the Senate Committee on the Judiciary and
the Subcommittee on the Constitution of the House Commit-
tee on the Judiciary, 105th Cong., 1st Sess., 45 (1995) (herein-
after S. 6 and H. R. 929 Joint Hearing). The physician will
then either crush the skull or will use a vacuum to remove
the brain and other intracranial contents from the fetal skull,
collapse the fetus’ head, and pull the fetus from the uterus.
11 F. Supp. 2d, at 1106.7
Use of the partial birth abortion procedure achieved prom-
inence as a national issue after it was publicly described by
Dr. Martin Haskell, in a paper entitled “Dilation and Extrac-
tion for Late Second Trimester Abortion,” at the National
Abortion Federation’s September 1992 Risk Management
Seminar. In that paper, Dr. Haskell described his version
of the procedure as follows:
“With a lower [fetal] extremity in the vagina, the
surgeon uses his fingers to deliver the opposite lower
performed the procedure on patients 20 through 24 weeks and on certain
patients 25 through 26 weeks. See H. R. 1833 Hearing 36.
7 There are, in addition, two forms of abortion that are used only rarely:
hysterotomy, a procedure resembling a Caesarean section, requires the
surgical delivery of the fetus through an incision on the uterine wall, and
hysterectomy. 11 F. Supp. 2d, at 1109.

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extremity, then the torso, the shoulders and the upper
extremities.
“The skull lodges at the internal cervical os. Usually
there is not enough dilation for it to pass through. The
fetus is oriented dorsum or spine up.
“At this point, the right-handed surgeon slides the
fingers of the left hand along the back of the fetus and
‘hooks’ the shoulders of the fetus with the index and
ring fingers (palm down).
“[T]he surgeon takes a pair of blunt curved Metzen-
baum scissors in the right hand. He carefully advances
the tip, curved down, along the spine and under his mid-
dle finger until he feels it contact the base of the skull
under the tip of his middle finger.
“[T]he surgeon then forces the scissors into the base
of the skull or into the foramen magnum. Having
safely entered the skull, he spreads the scissors to en-
large the opening.
“The surgeon removes the scissors and introduces a
suction catheter into this hole and evacuates the skull
contents. With the catheter still in place, he applies
traction to the fetus, removing it completely from the
patient.” H. R. 1833 Hearing 3, 8–9.
In cases in which the physician inadvertently dilates the
woman to too great a degree, the physician will have to hold
the fetus inside the woman so that he can perform the proce-
dure. Id., at 80 (statement of Pamela Smith, M. D.) (“In
these procedures, one basically relies on cervical entrapment
of the head, along with a firm grip, to help keep the baby in
place while the practitioner plunges a pair of scissors into
the base of the baby’s skull”). See also S. 6 and H. R. 929
Joint Hearing 45 (“I could put dilapan in for four or five days
and say I’m doing a D&E procedure and the fetus could just
fall out. But that’s not really the point. The point here is
you’re attempting to do an abortion . . . . Not to see how do

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Thomas, J., dissenting
I manipulate the situation so that I get a live birth instead”)
(quoting Dr. Haskell).
II
Nebraska, along with 29 other States, has attempted to
ban the partial birth abortion procedure. Although the Ne-
braska statute purports to prohibit only “partial birth abor-
tion,” a phrase which is commonly used, as I mentioned, to
refer to the breech extraction version of intact D&E, the
majority concludes that this statute could also be read in
some future case to prohibit ordinary D&E, the first proce-
dure described above. According to the majority, such an
application would pose a substantial obstacle to some women
seeking abortions and, therefore, the statute is unconstitu-
tional. The majority errs with its very first step. I think
it is clear that the Nebraska statute does not prohibit the
D&E procedure. The Nebraska partial birth abortion stat-
ute at issue in this case reads as follows:
“No partial-birth abortion shall be performed in this
state, unless such procedure is necessary to save the life
of the mother whose life is endangered by a physical
disorder, physical illness, or physical injury, including
a life-endangering physical condition caused by or aris-
ing from the pregnancy itself.” Neb. Rev. Stat. Ann.
§ 28–328(1) (Supp. 1999).
“Partial birth abortion” is defined in the statute as
“an abortion procedure in which the person performing
the abortion partially delivers vaginally a living unborn
child before killing the unborn child and completing the
delivery. For purposes of this subdivision, the term
partially delivers vaginally a living unborn child before
killing the unborn child means deliberately and inten-
tionally delivering into the vagina a living unborn child,
or a substantial portion thereof, for the purpose of per-
forming a procedure that the person performing such

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990 STENBERG v. CARHART
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procedure knows will kill the unborn child and does kill
the unborn child.” § 28–326(9).
A
Starting with the statutory definition of “partial birth
abortion,” I think it highly doubtful that the statute could
be applied to ordinary D&E. First, the Nebraska statute
applies only if the physician “partially delivers vaginally a
living unborn child,” which phrase is defined to mean “delib-
erately and intentionally delivering into the vagina a living
unborn child, or a substantial portion thereof.” § 28–326(9)
(emphases added). When read in context, the term “par-
tially delivers” cannot be fairly interpreted to include remov-
ing pieces of an unborn child from the uterus one at a time.
The word “deliver,” particularly delivery of an “unborn
child,” refers to the process of “assist[ing] in giving birth,”
which suggests removing an intact unborn child from the
womb, rather than pieces of a child. See Webster’s Ninth
New Collegiate Dictionary 336 (1991) (defining “deliver” as
“to assist in giving birth; to aid in the birth of ”); Stedman’s
Medical Dictionary 409 (26th ed. 1995) (“To assist a woman
in childbirth”). Without question, one does not “deliver” a
child when one removes the child from the uterus piece by
piece, as in a D&E. Rather, in the words of respondent and
his experts, one “remove[s]” or “dismember[s]” the child in a
D&E. App. 45, 55 (testimony of Dr. Carhart) (referring to
the act of removing the fetus in a D&E); id., at 150 (testi-
mony of Dr. Hodgson) (same); id., at 267 (testimony of
Dr. Stubblefield) (physician “dismember[s]” the fetus). See
also H. R. 1833 Hearing 3, 8 (Dr. Haskell describing “deliv-
ery” of part of the fetus during a D&X). The majority cites
sources using the terms “deliver” and “delivery” to refer to
removal of the fetus and the placenta during birth. But
these sources also presume an intact fetus, rather than dis-
membered fetal parts. See Obstetrics: Normal & Problem
Pregnancies 388 (S. Gabbe, J. Niebyl, & J. Simpson eds., 3d

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Thomas, J., dissenting
ed. 1996) (“After delivery [of infant and placenta], the pla-
centa, cord, and membranes should be examined”); 4 Oxford
English Dictionary 421, 422 (2d ed. 1989) (“To disburden (a
woman) of the foetus, to bring to childbirth”); B. Maloy, Med-
ical Dictionary for Lawyers 221 (2d ed. 1989) (“To aid in the
process of childbirth; to bring forth; to deliver the fetus, pla-
centa”). The majority has pointed to no source in which
“delivery” is used to refer to removal of first a fetal arm,
then a leg, then the torso, etc. In fact, even the majority
describes the D&E procedure without using the word “de-
liver” to refer to the removal of fetal tissue from the uterus.
See ante, at 939 (“pulling a ‘substantial portion’ of a still
living fetus” (emphasis added)); ibid. (“portion of a living
fetus has been pulled into the vagina” (emphasis added)).
No one, including the majority, understands the act of pulling
off a part of a fetus to be a “delivery.”
To make the statute’s meaning even more clear, the statute
applies only if the physician “partially delivers vaginally a
living unborn child before killing the unborn child and com-
pleting the delivery.” The statute defines this phrase to
mean that the physician must complete the delivery “for the
purpose of performing a procedure” that will kill the unborn
child. It is clear from these phrases that the procedure that
kills the fetus must be subsequent to, and therefore separate
from, the “partia[l] deliver[y]” or the “deliver[y] into the
vagina” of “a living unborn child or substantial portion
thereof.” In other words, even if one assumes, arguendo,
that dismemberment—the act of grasping a fetal arm or leg
and pulling until it comes off, leaving the remaining part of
the fetal body still in the uterus—is a kind of “delivery,” it
does not take place “before” the death-causing procedure or
“for the purpose of performing” the death-causing proce-
dure; it is the death-causing procedure. Under the majori-
ty’s view, D&E is covered by the statute because when the
doctor pulls on a fetal foot until it tears off he has “delivered”
a substantial portion of the unborn child and has performed

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a procedure known to cause death. But, significantly, the
physician has not “delivered” the child before performing the
death-causing procedure or “for the purpose of ” performing
the death-causing procedure; the dismemberment “delivery”
is itself the act that causes the fetus’ death.8
Moreover, even if removal of a fetal foot or arm from the
uterus incidental to severing it from the rest of the fetal
body could amount to delivery before, or for the purpose of,
performing a death-causing procedure, the delivery would
not be of an “unborn child, or a substantial portion thereof.”
And even supposing that a fetal foot or arm could conceiv-
ably be a “substantial portion” of an unborn child, both the
common understanding of “partial birth abortion” and the
principle that statutes will be interpreted to avoid consti-
tutional difficulties would require one to read “substantial”
otherwise. See infra, at 996–997.
B
Although I think that the text of § 28–326(9) forecloses any
application of the Nebraska statute to the D&E procedure,
even if there were any ambiguity, the ambiguity would be
conclusively resolved by reading the definition in light of the
fact that the Nebraska statute, by its own terms, applies only
to “partial birth abortion,” § 28–328(1). By ordinary rules
of statutory interpretation, we should resolve any ambiguity
in the specific statutory definition to comport with the com-
mon understanding of “partial birth abortion,” for that term
itself, no less than the specific definition, is part of the stat-
8 The majority argues that the statute does not explicitly require that
the death-causing procedure be separate from the overall abortion proce-
dure. That is beside the point; under the statute the death-causing proce-
dure must be separate from the delivery. Moreover, it is incorrect to
state that the statute contemplates only one “procedure.” The statute
clearly uses the term “procedure” to refer to both the overall abortion
procedure (“partial birth abortion” is “an abortion procedure”) as well as
to a component of the overall abortion procedure (“for the purpose of per-
forming a procedure . . . that will kill the unborn child”).

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Thomas, J., dissenting
ute. United States v. Morton, 467 U. S. 822, 828 (1984) (“We
do not . . . construe statutory phrases in isolation; we read
statutes as a whole”).9
“Partial birth abortion” is a term that has been used by a
majority of state legislatures, the United States Congress,
medical journals, physicians, reporters, even judges, and has
never, as far as I am aware, been used to refer to the D&E
procedure. The number of instances in which “partial birth
abortion” has been equated with the breech extraction form
of intact D&E (otherwise known as “D&X”) 10 and explicitly
contrasted with D&E, are numerous. I will limit myself to
just a few examples.
First, numerous medical authorities have equated “partial
birth abortion” with D&X. The AMA has done so and has
recognized that the procedure is “different from other de-
structive abortion techniques because the fetus . . . is killed
outside of the womb.” AMA Board of Trustees Factsheet
on H. R. 1122 (June 1997), in App. to Brief for Association of
American Physicians and Surgeons et al. as Amici Curiae 1.
Medical literature has also equated “partial birth abortion”
with D&X as distinguished from D&E. See Gynecologic,
Obstetric, and Related Surgery, at 1043; Sprang & Neerhof,
Rationale for Banning Abortions Late in Pregnancy, 280
JAMA 744 (Aug. 26, 1998); Bopp & Cook, Partial Birth Abor-
tion: The Final Frontier of Abortion Jurisprudence, 14 Is-
sues in Law and Medicine 3 (1998). Physicians have equated
“partial birth abortion” with D&X. See Planned Parent-
hood v. Doyle, 44 F. Supp. 2d 975, 999 (WD Wis. 1999) (citing
testimony); Richmond Medical Center for Women v. Gil-
9 It is certainly true that an undefined term must be construed in accord-
ance with its ordinary and plain meaning. FDIC v. Meyer, 510 U. S. 471,
476 (1994). But this does not mean that the ordinary and plain meaning
of a term is wholly irrelevant when that term is defined.
10 As noted, see n. 5, supra, there is no consensus regarding which of
these terms is appropriate to describe the procedure. I assume, as the
majority does, that the terms are, for purposes here, interchangeable.

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more, 55 F. Supp. 2d 441, 455 (ED Va. 1999) (citing testi-
mony). Even respondent’s expert, Dr. Phillip Stubblefield,
acknowledged that breech extraction intact D&E is referred
to in the lay press as “partial birth abortion.” App. 271.
Second, the lower courts have repeatedly acknowledged
that “partial birth abortion” is commonly understood to
mean D&X. See Little Rock Family Planning Services v.
Jegley, 192 F. 3d 794, 795 (CA8 1999) (“The term ‘partial-
birth abortion,’ . . . is commonly understood to refer to a
particular procedure also known as intact dilation and ex-
traction”); Planned Parenthood of Greater Iowa, Inc. v.
Miller, 195 F. 3d 386, 387 (CA8 1999) (“The [Iowa] Act pro-
hibits ‘partial-birth abortion,’ a term commonly understood
to refer to a procedure called a dilation and extraction
(D&X)”). The District Court in this case noted that
“[p]artial-birth abortions” are “known medically as intact di-
lation and extraction or D&X.” 11 F. Supp. 2d, at 1121,
n. 26. Even the majority notes that “partial birth abortion”
is a term “ordinarily associated with the D&X procedure.”
Ante, at 942.
Third, the term “partial birth abortion” has been used in
state legislation on 28 occasions and by Congress twice.
The term “partial birth abortion” was adopted by Congress
in both 1995 and 1997 in two separate pieces of legislation
prohibiting the procedure.11 In considering the legislation,
11 Congressional legislation prohibiting the procedure was first intro-
duced in June 1995, with the introduction of the Partial Birth Abortion
Ban Act, H. R. 1833. This measure, which was sponsored by 165 individ-
ual House Members, passed both Houses by wide margins, 141 Cong. Rec.
35892 (1995); 142 Cong. Rec. 31169 (1996), but was vetoed by President
Clinton, see id., at 7467. The House voted to override the veto on Sep-
tember 19, 1996, see id., at 23851; however, the Senate failed to override
by a margin of 13 votes, see id., at 25829. In the next Congress, 181
individual House cosponsors reintroduced the Partial Birth Abortion Ban
Act as H. R. 929, which was later replaced in the House with H. R. 1122.
See H. R. 1122, 105th Cong., 1st Sess. (1997). The House and Senate
again adopted the legislation, as amended, by wide margins. See 143

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Thomas, J., dissenting
Congress conducted numerous hearings and debates on the
issue, which repeatedly described “partial birth abortion” as
a procedure distinct from D&E. The Congressional Record
contained numerous references to Dr. Haskell’s procedure.
See, e. g., H. R. 1833 Hearing 3, 17, 52, 77; S. 6 and H. R. 929
Joint Hearing 45. Since that time, debates have taken place
in state legislatures across the country, 30 of which have
voted to prohibit the procedure. With only two exceptions,
the legislatures that voted to ban the procedure referred to
it as “partial birth abortion.” 12 These debates also referred
to Dr. Haskell’s procedure as D&X. Both the evidence be-
fore the legislators and the legislators themselves equated
“partial birth abortion” with D&X. The fact that 28 States
adopted legislation banning “partial birth abortion,” defined
it in a way similar or identical to Nebraska’s definition,13 and,
Cong. Rec. H1230 (Mar. 20, 1997); id., at S4715 (May 20, 1997). President
Clinton again vetoed the bill. See id., at H8891 (Oct. 10, 1997). Again,
the veto override passed in the House and fell short in the Senate. See
144 Cong. Rec. H6213 (July 23, 1998); id., at S10564 (Sept. 18, 1998).
12 Consistent with the practice of Dr. Haskell (an Ohio practitioner), Ohio
referred to the procedure as “dilation and extraction,” defined as “the
termination of a human pregnancy by purposely inserting a suction device
into the skull of a fetus to remove the brain.” Ohio Rev. Code Ann.
§ 2919.15(A) (1997). Missouri refers to the killing of a “partially-born”
infant as “infanticide.” Mo. Stat. Ann. § 565.300 (Vernon Supp. 2000).
13 For the most part, these States defined the term “partial birth abor-
tion” using language similar to that in the 1995 proposed congressional
legislation, that is “an abortion in which the person performing the abor-
tion partially vaginally delivers a living fetus before killing the fetus and
completing the delivery.” See H. R. 1833 Hearing 210. See, e. g., Alaska
Stat. Ann. § 18.16.050 (1998); Ariz. Rev. Stat. Ann. § 13–3603.01 (Supp.
1999); Ark. Code Ann. § 5–61–202 (1997); Fla. Stat. § 390.011 (Supp. 2000);
Ill. Comp. Stat., ch. 720, § 513/5 (1999); Ind. Code Ann. § 16–18–2–267.5
(West Supp. 1999); Mich. Comp. Laws Ann. § 333.17016(5)(c) (West Supp.
2000); Miss. Code Ann. § 41–41–73(2)(a) (Supp. 1998); S. C. Code Ann. § 44–
41–85(A)(1) (1999 Cum. Supp.). Other States, including Nebraska, see
Neb. Rev. Stat. Ann. § 28–326 (Supp. 1999), defined “partial-birth abortion”
using language similar to that used in the 1997 proposed congressional

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Thomas, J., dissenting
in doing so, repeatedly referred to the breech extraction
form of intact D&E and repeatedly distinguished it from or-
dinary D&E, makes it inconceivable that the term “partial
birth abortion” could reasonably be interpreted to mean
D&E.
C
Were there any doubt remaining whether the statute could
apply to a D&E procedure, that doubt is no ground for invali-
dating the statute. Rather, we are bound to first consider
whether a construction of the statute is fairly possible that
would avoid the constitutional question. Erznoznik v. Jack-
sonville, 422 U. S. 205, 216 (1975) (“[A] state statute should
not be deemed facially invalid unless it is not readily subject
to a narrowing construction by the state courts”); Frisby v.
Schultz, 487 U. S. 474, 482 (1988) (“The precise scope of the
ban is not further described within the text of the ordinance,
but in our view the ordinance is readily subject to a narrow-
ing construction that avoids constitutional difficulties”).
This principle is, as Justice O’Connor has said, so “well-
established” that failure to apply is “plain error.” Id., at
483. Although our interpretation of a Nebraska law is of
course not binding on Nebraska courts, it is clear, as Erznoz-
nik and Frisby demonstrate, that, absent a conflicting inter-
pretation by Nebraska (and there is none here), we should,
if the text permits, adopt such a construction.
legislation, which retained the definition of partial birth abortion used in
the 1995 bill, that is “an abortion in which the person performing the
abortion partially vaginally delivers a living fetus before killing the fetus
and completing the delivery,” but further defined that phrase to mean
“deliberately and intentionally delivers into the vagina a living fetus, or a
substantial portion there of, for the purpose of performing a procedure
the physician knows will kill the fetus, and kills the fetus.” See Partial
Birth Abortion Ban Act of 1997, H. R. 1122, 105th Cong., 1st Sess. (1997).
See, e. g., Idaho Code § 18– 613(a) (Supp. 1999); Iowa Code Ann.
§ 707.8A(1)(c) (Supp. 1999); N. J. Stat. Ann. § 2A:65A–6(e) (West Supp.
2000); Okla. Stat. Ann., Tit. 21, § 684 (Supp. 2000); R. I. Gen. Laws § 23–
4.12–1 (Supp. 1999); Tenn. Code Ann. § 39–15–209(a)(1) (1997).

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Thomas, J., dissenting
The majority contends that application of the Nebraska
statute to D&E would pose constitutional difficulties because
it would eliminate the most common form of second-
trimester abortions. To the extent that the majority’s con-
tention is true, there is no doubt that the Nebraska statute
is susceptible of a narrowing construction by Nebraska
courts that would preserve a physicians’ ability to perform
D&E. See State v. Carpenter, 250 Neb. 427, 434, 551 N. W.
2d 518, 524 (1996) (“A penal statute must be construed so as
to meet constitutional requirements if such can reasonably
be done”). For example, the statute requires that the physi-
cian “deliberately and intentionally delive[r] into the vagina
a living unborn child, or a substantial portion thereof,” be-
fore performing a death-causing procedure. The term “sub-
stantial portion” is susceptible to a narrowing construction
that would exclude the D&E procedure. One definition of
the word “substantial” is “being largely but not wholly that
which is specified.” Webster’s Ninth New Collegiate Dic-
tionary, at 1176. See Pierce v. Underwood, 487 U. S. 552,
564 (1988) (describing different meanings of the term “sub-
stantial”). In other words, “substantial” can mean “almost
all” of the thing denominated. If nothing else, a court could
construe the statute to require that the fetus be “largely, but
not wholly,” delivered out of the uterus before the physician
performs a procedure that he knows will kill the unborn
child. Or, as I have discussed, a court could (and should)
construe “for the purpose of performing a procedure” to
mean “for the purpose of performing a separate procedure.”
III
The majority and Justice O’Connor reject the plain lan-
guage of the statutory definition, refuse to read that defini-
tion in light of the statutory reference to “partial birth abor-
tion,” and ignore the doctrine of constitutional avoidance.
In so doing, they offer scant statutory analysis of their own.
See ante, at 938–940 (majority opinion); cf. ante, at 940–945

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998 STENBERG v. CARHART
Thomas, J., dissenting
(majority opinion); ante, at 948–949 (O’Connor, J., concur-
ring). In their brief analyses, the majority and Justice
O’Connor disregard all of the statutory language except for
the final definitional sentence, thereby violating the funda-
mental canon of construction that statutes are to be read as
a whole. United States v. Morton, 467 U. S., at 828 (“We do
not . . . construe statutory phrases in isolation; we read stat-
utes as a whole. Thus, the words [in question] must be read
in light of the immediately following phrase”) (footnote omit-
ted)); United States v. Heirs of Boisdore´, 8 How. 113, 122
(1849) (“In expounding a statute, we must not be guided by
a single sentence or member of a sentence, but look to the
provisions of the whole law, and to its object and policy”);
Gustafson v. Alloyd Co., 513 U. S. 561, 575 (1995) (“[A] word
is known by the company it keeps”).14 In lieu of analyzing
the statute as a whole, the majority and Justice O’Connor
14 The majority argues that its approach is supported by Meese v. Keene,
481 U. S. 465, 487 (1987), in which the Court stated that “the statutory
definition of [a] term excludes unstated meanings of that term.” But this
case provides no support for the approach adopted by the majority and
Justice O’Connor. In Meese, the Court addressed a statute that used
the term “political propaganda.” Id., at 470. The Court noted that there
were two commonly understood meanings to the term “political propa-
ganda,” id., at 477, and, not surprisingly, chose the definition that was
most consistent with the statutory definition, id., at 485. Nowhere did
the Court suggest that, because “political propaganda” was defined in the
statute, the commonly understood meanings of that term were irrelevant.
Indeed, a significant portion of the Court’s opinion was devoted to describ-
ing the effect of Congress’ use of that term. Id., at 477–479, 483–484. So
too, Colautti v. Franklin, 439 U. S. 379, 392–393, n. 10 (1979), and Western
Union Telegraph Co. v. Lenroot, 323 U. S. 490 (1945), support the proposi-
tion that when there are two possible interpretations of a term, and only
one comports with the statutory definition, the term should not be read
to include the unstated meaning. But here, there is only one possible
interpretation of “partial birth abortion”—the majority can cite no author-
ity using that term to describe D&E—and so there is no justification for
the majority’s willingness to entirely disregard the statute’s use of that
term.

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Thomas, J., dissenting
offer five principal arguments for their interpretation of the
statute. I will address them in turn.
First, the majority appears to accept, if only obliquely, an
argument made by respondent: If the term “partial birth
abortion” refers to only the breech extraction form of intact
D&E, or D&X, the Nebraska Legislature should have used
the medical nomenclature. See ante, at 943 (noting that the
Nebraska Legislature rejected an amendment that would re-
place “partial birth abortion” with “dilation and extraction”);
Brief for Respondent 4–5, 24.
There is, of course, no requirement that a legislature use
terminology accepted by the medical community. A legisla-
ture could, no doubt, draft a statute using the term “heart
attack” even if the medical community preferred “myocardial
infarction.” Legislatures, in fact, sometimes use medical
terms in ways that conflict with their clinical definitions, see,
e. g., Barber v. Director, 43 F. 3d 899, 901 (CA4 1995) (noting
that the medical definition of “pneumoconiosis” is only a sub-
set of the afflictions that fall within the definition of “pneu-
moconiosis” in the Black Lung Act), a practice that is unre-
markable so long as the legal term is adequately defined.
We have never, until today, suggested that legislature may
only use words accepted by every individual physician.
Rather, “we have traditionally left to legislators the task of
defining terms of a medical nature that have legal signifi-
cance.” Kansas v. Hendricks, 521 U. S. 346, 359 (1997).
And we have noted that “[o]ften, those definitions do not fit
precisely with the definitions employed by the medical com-
munity.” Ibid.
Further, it is simply not true that the many legislatures,
including Nebraska’s, that prohibited “partial birth abortion”
chose to use a term known only in the vernacular in place
of a term with an accepted clinical meaning. When the
Partial-Birth Abortion Ban Act of 1995 was introduced in
Congress, the term “dilation and extraction” did not appear
in any medical dictionary. See, e. g., Dorland’s Illustrated

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1000 STENBERG v. CARHART
Thomas, J., dissenting
Medical Dictionary 470 (28th ed. 1994); Stedman’s Medical
Dictionary, at 485; Miller-Keane Encyclopedia & Dictionary
of Medicine, Nursing, & Allied Health 460 (6th ed. 1997); The
Sloane-Dorland Annotated Medical-Legal Dictionary 204
(1987); I. Dox, J. Melloni, & G. Eisher, The HarperCollins
Illustrated Medical Dictionary 131 (1993). The term did not
appear in descriptions of abortion methods in leading medi-
cal textbooks. See, e. g., G. Cunningham et al., Williams Ob-
stetrics 579–605 (20th ed. 1997); Obstetrics: Normal & Prob-
lem Pregnancies, at 1249–1279; W. Hern, Abortion Practice
(1990). Abortion reference books also omitted any refer-
ence to the term. See, e. g., Modern Methods of Inducing
Abortion (D. Baird, D. Grimes, & P. Van Look eds. 1995);
E. Glick, Surgical Abortion (1998).15
Not only did D&X have no medical meaning at the time,
but the term is ambiguous on its face. “Dilation and extrac-
tion” would, on its face, accurately describe any procedure
in which the woman is “dilated” and the fetus “extracted,”
including D&E. See supra, at 984–985. In contrast, “par-
tial birth abortion” has the advantage of faithfully describing
the procedure the legislature meant to address because the
fact that a fetus is “partially born” during the procedure is
indisputable. The term “partial birth abortion” is com-
pletely accurate and descriptive, which is perhaps the reason
why the majority finds it objectionable. Only a desire to
find fault at any cost could explain the Court’s willingness to
penalize the Nebraska Legislature for failing to replace a
15 Nor, for that matter, did the terms “intact dilation and extraction” or
“intact dilation and evacuation” appear in textbooks or medical dictionar-
ies. See supra, at 999 and this page. In fact, respondent’s preferred
term “intact D&E” would compound, rather than remedy, any confusion
regarding the statute’s meaning. As is evident from the majority opinion,
there is no consensus on what this term means. Compare ante, at 927
(describing “intact D&E” to refer to both breech and vertex presentation
procedures), with App. 6 (testimony of Dr. Henshaw) (using “intact D&E”
to mean only breech procedure), with id., at 275 (testimony of Dr. Stub-
blefield) (using “intact D&E” to refer to delivery of fetus that has died
in utero).

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Thomas, J., dissenting
descriptive term with a vague one. There is, therefore,
nothing to the majority’s argument that the Nebraska Legis-
lature is at fault for declining to use the term “dilation and
extraction.” 16
Second, the majority faults the Nebraska Legislature for
failing to “track the medical differences between D&E and
D&X” and for failing to “suggest that its application turns
on whether a portion of the fetus’ body is drawn into the
vagina as part of a process to extract an intact fetus after
collapsing the head as opposed to a process that would dis-
member the fetus.” Ante, at 939. I have already explained
why the Nebraska statute reflects the medical differences
between D&X and D&E. To the extent the majority means
that the Nebraska Legislature should have “tracked the
medical differences” by adopting one of the informal defini-
tions of D&X, this argument is without merit; none of these
definitions would have been effective to accomplish the
State’s purpose of preventing abortions of partially born fe-
tuses. Take, for example, ACOG’s informal definition of the
term “intact D&X.” According to ACOG, an “intact D&X”
consists of the following four steps: (1) deliberate dilation of
16 The fact that the statutory term “partial birth abortion” may express
a political or moral judgment, whereas “dilation and extraction” does not,
is irrelevant. It is certainly true that technical terms are frequently
empty of normative content. (Of course, the decision to use a technical
term can itself be normative. See ante, passim (majority opinion)). But,
so long as statutory terms are adequately defined, there is no requirement
that Congress or state legislatures draft statutes using morally agnostic
terminology. See, e. g., 18 U. S. C. § 922(v) (making it unlawful to “manu-
facture, transfer, or possess a semiautomatic assault weapon”); Kobay-
ashi & Olson et al., In re 101 California Street: A Legal and Economic
Analysis of Strict Liability for the Manufacture and Sale of “Assault Weap-
ons,” 8 Stan. L. & Pol’y Rev. 41, 43 (1997) (“Prior to 1989, the term ‘assault
weapon’ did not exist in the lexicon of firearms. It is a political term,
developed by anti-gun publicists to expand the category of ‘assault rifles’
so as to allow an attack on as many additional firearms as possible on
the basis of undefined ‘evil’ appearance”). See also Meese, 481 U. S., at
484–485.

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1002 STENBERG v. CARHART
Thomas, J., dissenting
the cervix, usually over a sequence of days; (2) instrumental
conversion of the fetus to a footling breach; (3) breech extrac-
tion of the body excepting the head; and (4) partial evacua-
tion of the intracranial contents of a living fetus to effect
vaginal delivery of a dead but otherwise intact fetus. App.
599–600 (ACOG Executive Board, Statement on Intact Dila-
tion and Extraction (Jan. 12, 1997)). ACOG emphasizes that
“unless all four elements are present in sequence, the proce-
dure is not an intact D&X.” Id., at 600. Had Nebraska
adopted a statute prohibiting “intact D&X,” and defined it
along the lines of the ACOG definition, physicians attempting
to perform abortions on partially born fetuses could have
easily evaded the statute. Any doctor wishing to perform a
partial birth abortion procedure could simply avoid liability
under such a statute by performing the procedure, as re-
spondent does, only when the fetus is presented feet first,
thereby avoiding the necessity of “conversion of the fetus to
a footling breech.” Id., at 599. Or, a doctor could convert
the fetus without instruments. Or, the doctor could cause
the fetus’ death before “partial evacuation of the intracranial
contents,” id., at 600, by plunging scissors into the fetus’
heart, for example. A doctor could even attempt to evade
the statute by chopping off two fetal toes prior to completing
delivery, preventing the State from arguing that the fetus
was “otherwise intact.” Presumably, however, Nebraska,
and the many other legislative bodies that adopted partial
birth abortion bans, were not concerned with whether death
was inflicted by injury to the brain or the heart, whether the
fetus was converted with or without instruments, or whether
the fetus died with its toes attached. These legislative bod-
ies were, I presume, concerned with whether the child was
partially born before the physician caused its death. The
legislatures’ evident concern was with permitting a proce-
dure that resembles infanticide and threatens to dehumanize
the fetus. They, therefore, presumably declined to adopt a

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Thomas, J., dissenting
ban only on “intact D&X,” as defined by ACOG, because it
would have been ineffective to that purpose. Again, the
majority is faulting Nebraska for a legitimate legislative
calculation.
Third, the majority and Justice O’Connor argue that
this Court generally defers to lower federal courts’ interpre-
tations of state law. Ante, at 940 (majority opinion); ante,
at 949 (O’Connor, J., concurring). However, a decision
drafted by Justice O’Connor, which she inexplicably fails
to discuss, Frisby v. Schultz, 487 U. S. 474 (1988), makes clear
why deference is inappropriate here. As Justice O’Con-
nor explained in that case:
“[W]hile we ordinarily defer to lower court construc-
tions of state statutes, we do not invariably do so. We
are particularly reluctant to defer when the lower courts
have fallen into plain error, which is precisely the situa-
tion presented here. To the extent they endorsed a
broad reading of the ordinance, the lower courts ran
afoul of the well-established principle that statutes will
be interpreted to avoid constitutional difficulties.” Id.,
at 483 (citations omitted).
Frisby, then, identifies exactly why the lower courts’ opin-
ions here are not entitled to deference: The lower courts
failed to identify the narrower construction that, consistent
with the text, would avoid any constitutional difficulties.
Fourth, the majority speculates that some Nebraska
prosecutor may attempt to stretch the statute to apply it to
D&E. But a state statute is not unconstitutional on its face
merely because we can imagine an aggressive prosecutor
who would attempt an overly aggressive application of the
statute. We have noted that “ ‘[w]ords inevitably contain
germs of uncertainty.’ ” Broadrick v. Oklahoma, 413 U. S.
601, 608 (1973). We do not give statutes the broadest defi-
nition imaginable. Rather, we ask whether “the ordinary

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1004 STENBERG v. CARHART
Thomas, J., dissenting
person exercising ordinary common sense can sufficiently un-
derstand and comply with [the statute].” Ibid. (quoting
Civil Service Comm’n v. Letter Carriers, 413 U. S. 548, 579
(1973)). While a creative legal mind might be able to stretch
the plain language of the Nebraska statute to apply to D&E,
“citizens who desire to obey the statute will have no diffi-
culty in understanding it.” Colten v. Kentucky, 407 U. S.
104, 110 (1972) (internal quotation marks omitted).
Finally, the majority discusses at some length the reasons
it will not defer to the interpretation of the statute proffered
by the Nebraska Attorney General, despite the Attorney
General’s repeated representations to this Court that his
State will not apply the partial birth abortion statute to
D&E. See Brief for Petitioners 11–13; Tr. of Oral Arg. 10–
11. The fact that the Court declines to defer to the inter-
pretation of the Attorney General is not, however, a reason
to give the statute a contrary representation. Even without
according the Attorney General’s view any particular re-
spect, we should agree with his interpretation because it is
undoubtedly the correct one. Moreover, Justice O’Connor
has noted that the Court should adopt a narrow interpreta-
tion of a state statute when it is supported by the principle
that statutes will be interpreted to avoid constitutional dif-
ficulties as well as by “the representations of counsel . . . at
oral argument.” Frisby v. Schultz, supra, at 483. Such an
approach is particularly appropriate in this case because, as
the majority notes, Nebraska courts accord the Nebraska At-
torney General’s interpretations of state statutes “substan-
tial weight.” See State v. Coffman, 213 Neb. 560, 561, 330
N. W. 2d 727, 728 (1983). Therefore, any renegade prosecu-
tor bringing criminal charges against a physician for per-
forming a D&E would find himself confronted with a con-
trary interpretation of the statute by the Nebraska Attorney
General, and, I assume, a judge who both possessed common

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Thomas, J., dissenting
sense and was aware of the rule of lenity. See State v.
White, 254 Neb. 566, 575, 577 N. W. 2d 741, 747 (1998).17
IV
Having resolved that Nebraska’s partial birth abortion
statute permits doctors to perform D&E abortions, the ques-
tion remains whether a State can constitutionally prohibit
the partial birth abortion procedure without a health excep-
tion. Although the majority and Justice O’Connor pur-
port to rely on the standard articulated in the Casey plural-
ity in concluding that a State may not, they in fact disregard
it entirely.
A
Though Justices O’Connor, Kennedy, and Souter de-
clined in Casey, on the ground of stare decisis, to reconsider
whether abortion enjoys any constitutional protection, 505
U. S., at 844–846, 854–869 (majority opinion); id., at 871 (plu-
rality opinion), Casey professed to be, in part, a repudiation
of Roe and its progeny. The Casey plurality expressly noted
that prior case law had undervalued the State’s interest in
potential life, 505 U. S., at 875–876, and had invalidated regu-
lations of abortion that “in no real sense deprived women of
the ultimate decision,” id., at 875. See id., at 871 (“Roe v.
Wade speaks with clarity in establishing . . . the State’s ‘im-
portant and legitimate interest in potential life.’ That por-
17 The majority relies on Justice Scalia’s observation in Crandon v.
United States, 494 U. S. 152 (1990), that “we have never thought that the
interpretation of those charged with prosecuting criminal statutes is enti-
tled to deference.” Id., at 177. But Justice Scalia was commenting on
the United States Attorney General’s overly broad interpretation of a fed-
eral statute, deference to which, as he said, would “turn the normal con-
struction of criminal statutes upside-down, replacing the doctrine of lenity
with a doctrine of severity.” Id., at 178. Here, the Nebraska Attorney
General has adopted a narrow view of a criminal statute, one that com-
ports with the rule of lenity (not to mention the statute’s plain meaning).

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1006 STENBERG v. CARHART
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tion of the decision in Roe has been given too little acknowl-
edgment” (citation omitted)). The plurality repeatedly
recognized the States’ weighty interest in this area. See
id., at 877 (“State . . . may express profound respect for the
life of the unborn”); id., at 878 (“the State’s profound interest
in potential life”); id., at 850 (majority opinion) (“profound
moral and spiritual implications of terminating a pregnancy,
even in its earliest stage”). And, the plurality expressed
repeatedly the States’ legitimate role in regulating abortion
procedures. See id., at 876 (“The very notion that the State
has a substantial interest in potential life leads to the conclu-
sion that not all regulations must be deemed unwarranted”);
id., at 875 (“Not all governmental intrusion [with abortion]
is of necessity unwarranted”). According to the plurality:
“The fact that a law which serves a valid purpose, one not
designed to strike at the right itself, has the incidental effect
of making it more difficult or more expensive to procure an
abortion cannot be enough to invalidate it.” Id., at 874.
The Casey plurality therefore adopted the standard: “Only
where state regulation imposes an undue burden on a wom-
an’s ability to make this decision does the power of the State
reach into the heart of the liberty protected by the Due Proc-
ess Clause.” Ibid. A regulation imposes an “undue bur-
den” only if it “has the effect of placing a substantial obstacle
in the path of a woman’s choice.” Id., at 877.
B
There is no question that the State of Nebraska has a valid
interest—one not designed to strike at the right itself—in
prohibiting partial birth abortion. Casey itself noted that
States may “express profound respect for the life of the un-
born.” Ibid. States may, without a doubt, express this
profound respect by prohibiting a procedure that approaches
infanticide, and thereby dehumanizes the fetus and trivial-
izes human life. The AMA has recognized that this proce-
dure is “ethically different from other destructive abortion

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Thomas, J., dissenting
techniques because the fetus, normally twenty weeks or
longer in gestation, is killed outside the womb. The ‘partial
birth’ gives the fetus an autonomy which separates it from
the right of the woman to choose treatments for her own
body.” AMA Board of Trustees Factsheet on H. R. 1122
(June 1997), in App. to Brief for Association of American
Physicians and Surgeons et al. as Amici Curiae 1. Thirty
States have concurred with this view.
Although the description of this procedure set forth above
should be sufficient to demonstrate the resemblance between
the partial birth abortion procedure and infanticide, the tes-
timony of one nurse who observed a partial birth abortion
procedure makes the point even more vividly:
“The baby’s little fingers were clasping and unclasp-
ing, and his little feet were kicking. Then the doctor
stuck the scissors in the back of his head, and the baby’s
arms jerked out, like a startle reaction, like a flinch, like
a baby does when he thinks he is going to fall.
“The doctor opened up the scissors, stuck a high-
powered suction tube into the opening, and sucked
the baby’s brains out. Now the baby went completely
limp.” H. R. 1833 Hearing 18 (statement of Brenda
Pratt Shafer).
The question whether States have a legitimate interest in
banning the procedure does not require additional authority.
See ante, at 961–964 (Kennedy, J., dissenting).18 In a civi-
18 I read the majority opinion to concede, if only implicitly, that the State
has a legitimate interest in banning this dehumanizing procedure. The
threshold question under Casey is whether the abortion regulation serves
a legitimate state interest. 505 U. S. 833 (1992). Only if the statute
serves a legitimate state interest is it necessary to consider whether the
regulation imposes a substantial obstacle to women seeking an abortion.
Ibid. The fact that the majority considers whether Nebraska’s statute
creates a substantial obstacle suggests that the Members of the majority
other than Justice Stevens and Justice Ginsburg have rejected
respondent’s threshold argument that the statute serves no legitimate
state purpose.

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1008 STENBERG v. CARHART
Thomas, J., dissenting
lized society, the answer is too obvious, and the contrary ar-
guments too offensive, to merit further discussion. But see
ante, at 946–947 (Stevens, J., concurring) (arguing that the
decision of 30 States to ban the partial birth abortion proce-
dure was “simply irrational” because other forms of abortion
were “equally gruesome”); ante, at 951–952 (Ginsburg, J.,
concurring) (similar).19
19 Justice Ginsburg seems to suggest that even if the Nebraska stat-
ute does not impose an undue burden on women seeking abortions, the
statute is unconstitutional because it has the purpose of imposing an undue
burden. Justice Ginsburg’s view is, apparently, that we can presume
an unconstitutional purpose because the regulation is not designed to save
any fetus from “destruction” or protect the health of pregnant women and
so must, therefore, be designed to “chip away at . . . Roe.” Ante, at 952.
This is a strange claim to make with respect to legislation that was
enacted in 30 individual States and was enacted in Nebraska by a vote of
45 to 1, Nebraska Legislative Journal, 95th Leg., 1st Sess., 2609 (1997).
Moreover, in support of her assertion that the Nebraska Legislature acted
with an unconstitutional purpose, Justice Ginsburg is apparently unable
to muster a single shred of evidence that the Nebraska legislation was
enacted to prevent women from obtaining abortions (a purpose to which
it would be entirely ineffective), let alone the kind of persuasive proof we
would require before concluding that a legislature acted with an unconsti-
tutional intent. In fact, as far as I can tell, Justice Ginsburg’s views
regarding the motives of the Nebraska Legislature derive from the views
of a dissenting Court of Appeals judge discussing the motives of legis-
lators of other States. Justice Ginsburg’s presumption is, in addition,
squarely inconsistent with Casey, which stated that States may enact leg-
islation to “express profound respect for the life of the unborn,” 505 U. S.,
at 877, and with our opinion in Mazurek v. Armstrong, 520 U. S. 968 (1997)
(per curiam), in which we stated:
“[E]ven assuming . . . that a legislative purpose to interfere with the con-
stitutionally protected right to abortion without the effect of interfering
with that right . . . could render the Montana law invalid—there is no
basis for finding a vitiating legislative purpose here. We do not assume
unconstitutional legislative intent even when statutes produce harmful re-
sults, see, e. g., Washington v. Davis, 426 U. S. 229, 246 (1976); much less
do we assume it when the results are harmless.” Id., at 972 (emphases
in original).

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C
The next question, therefore, is whether the Nebraska
statute is unconstitutional because it does not contain an ex-
ception that would allow use of the procedure whenever
“ ‘ “necessary, in appropriate medical judgment, for the pres-
ervation of the . . . health of the mother.” ’ ” Ante, at 930
(majority opinion) (quoting Casey, 505 U. S., at 879, in turn
quoting Roe, 410 U. S., at 164–165) (emphasis deleted). Ac-
cording to the majority, such a health exception is required
here because there is a “division of opinion among some med-
ical experts over whether D&X is generally safer [than
D&E], and an absence of controlled medical studies that
would help answer these medical questions.” Ante, at 936–
937. In other words, unless a State can conclusively estab-
lish that an abortion procedure is no safer than other proce-
dures, the State cannot regulate that procedure without
including a health exception. Justice O’Connor agrees.
Ante, at 947–948 (concurring opinion). The rule set forth by
the majority and Justice O’Connor dramatically expands
on our prior abortion cases and threatens to undo any state
regulation of abortion procedures.
The majority and Justice O’Connor suggest that their
rule is dictated by a straightforward application of Roe and
Casey. Ante, at 929–930 (majority opinion); ante, at 947–948
(O’Connor, J., concurring). But that is simply not true. In
Roe and Casey, the Court stated that the State may “regu-
late, and even proscribe, abortion except where it is neces-
sary, in appropriate medical judgment, for the preservation
of the life or health of the mother.” Roe, supra, at 165;
Casey, 505 U. S., at 879. Casey said that a health exception
must be available if “continuing her pregnancy would consti-
tute a threat” to the woman. Id., at 880 (majority opinion)
(emphasis added). Under these cases, if a State seeks to
prohibit abortion, even if only temporarily or under particu-
lar circumstances, as Casey says that it may, id., at 879 (plu-

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1010 STENBERG v. CARHART
Thomas, J., dissenting
rality opinion), the State must make an exception for cases
in which the life or health of the mother is endangered by
continuing the pregnancy. These cases addressed only the
situation in which a woman must obtain an abortion because
of some threat to her health from continued pregnancy. But
Roe and Casey say nothing at all about cases in which a phy-
sician considers one prohibited method of abortion to be pref-
erable to permissible methods. Today’s majority and Jus-
tice O’Connor twist Roe and Casey to apply to the situation
in which a woman desires—for whatever reason—an abor-
tion and wishes to obtain the abortion by some particular
method. See ante, at 929–931 (majority opinion); ante, at
947–948 (concurring opinion). In other words, the majority
and Justice O’Connor fail to distinguish between cases in
which health concerns require a woman to obtain an abortion
and cases in which health concerns cause a woman who de-
sires an abortion (for whatever reason) to prefer one method
over another.
It is clear that the Court’s understanding of when a health
exception is required is not mandated by our prior cases. In
fact, we have, post-Casey, approved regulations of methods
of conducting abortion despite the lack of a health exception.
Mazurek v. Armstrong, 520 U. S. 968, 971 (1997) (per cu-
riam) (reversing Court of Appeals holding that plaintiffs
challenging requirement that only physicians perform abor-
tions had a “ ‘fair chance of success’ ”); id., at 979 (Stevens,
J., dissenting) (arguing that the regulation was designed to
make abortion more difficult). And one can think of vast
bodies of law regulating abortion that are valid, one would
hope, despite the lack of health exceptions. For example,
physicians are presumably prohibited from using abortifa-
cients that have not been approved by the Food and Drug
Administration even if some physicians reasonably believe

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Thomas, J., dissenting
that these abortifacients would be safer for women than
existing abortifacients.20
The majority effectively concedes that Casey provides no
support for its broad health exception rule by relying on
pre-Casey authority, see ante, at 931, including a case that
was specifically disapproved of in Casey for giving too little
weight to the State’s interest in fetal life. See Casey, supra,
at 869, 882 (overruling the parts of Thornburgh v. American
College of Obstetricians and Gynecologists, 476 U. S. 747
(1986), that were “inconsistent with Roe’s statement that the
State has a legitimate interest in promoting the life or poten-
tial life of the unborn,” 505 U. S., at 870); id., at 893 (majority
opinion) (relying on Thornburgh, supra, at 783 (Burger, C. J.,
dissenting), for the proposition that the Court was expanding
on Roe in that case). Indeed, Justice O’Connor, who joins
the Court’s opinion, was on the Court for Thornburgh and
was in dissent, arguing that, under the undue-burden stand-
ard, the statute at issue was constitutional. See 476 U. S.,
at 828–832 (arguing that the challenged state statute was not
“unduly burdensome”). The majority’s resort to this case
proves my point that the holding today assumes that the
standard set forth in the Casey joint opinion is no longer
governing.
And even if I were to assume that the pre-Casey standards
govern, the cases cited by the majority provide no support
for the proposition that the partial birth abortion ban must
20 As I discuss below, the only question after Casey is whether a ban on
partial birth abortion without a health exception imposes an “undue bur-
den” on a woman seeking an abortion, meaning that it creates a “substan-
tial obstacle” for the woman. I assume that the Court does not discuss
the health risks with respect to undue burden, and instead suggests that
health risks are relevant to the necessity of a health exception, because a
marginal increase in safety risk for some women is clearly not an undue
burden within the meaning of Casey. At bottom, the majority is using the
health exception language to water down Casey’s undue-burden standard.

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1012 STENBERG v. CARHART
Thomas, J., dissenting
include a health exception because some doctors believe that
partial birth abortion is safer. In Thornburgh, Danforth,
and Doe, the Court addressed health exceptions for cases in
which continued pregnancy would pose a risk to the woman.
Thornburgh, supra, at 770; Planned Parenthood of Central
Mo. v. Danforth, 428 U. S. 52 (1976); Doe v. Bolton, 410 U. S.,
at 197. And in Colautti v. Franklin, 439 U. S. 379 (1979),
the Court explicitly declined to address whether a State can
constitutionally require a tradeoff between the woman’s
health and that of the fetus. The broad rule articulated by
the majority and by Justice O’Connor are unprecedented
expansions of this Court’s already expansive pre-Casey
jurisprudence.
As if this state of affairs were not bad enough, the major-
ity expands the health exception rule articulated in Casey in
one additional and equally pernicious way. Although Roe
and Casey mandated a health exception for cases in which
abortion is “necessary” for a woman’s health, the majority
concludes that a procedure is “necessary” if it has any com-
parative health benefits. Ante, at 937. In other words, ac-
cording to the majority, so long as a doctor can point to sup-
port in the profession for his (or the woman’s) preferred
procedure, it is “necessary” and the physician is entitled to
perform it. Ibid. See also ante, at 952 (Ginsburg, J., con-
curring) (arguing that a State cannot constitutionally “sto[p]
a woman from choosing the procedure her doctor ‘reasonably
believes’ ” is in her best interest). But such a health excep-
tion requirement eviscerates Casey’s undue-burden standard
and imposes unfettered abortion on demand. The exception
entirely swallows the rule. In effect, no regulation of abor-
tion procedures is permitted because there will always be
some support for a procedure and there will always be some
doctors who conclude that the procedure is preferable. If
Nebraska reenacts its partial birth abortion ban with a
health exception, the State will not be able to prevent physi-
cians like Dr. Carhart from using partial birth abortion as a
routine abortion procedure. This Court has now expressed

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Thomas, J., dissenting
its own conclusion that there is “highly plausible” support
for the view that partial birth abortion is safer, which, in
the majority’s view, means that the procedure is therefore
“necessary.” Ante, at 937. Any doctor who wishes to per-
form such a procedure under the new statute will be able to
do so with impunity. Therefore, Justice O’Connor’s assur-
ance that the constitutional failings of Nebraska’s statute can
be easily fixed, ante, at 950–951, is illusory. The majority’s
insistence on a health exception is a fig leaf barely covering
its hostility to any abortion regulation by the States—a hos-
tility that Casey purported to reject.21
D
The majority assiduously avoids addressing the actual
standard articulated in Casey—whether prohibiting partial
birth abortion without a health exception poses a substantial
obstacle to obtaining an abortion. 505 U. S., at 877. And
for good reason: Such an obstacle does not exist. There are
two essential reasons why the Court cannot identify a sub-
stantial obstacle. First, the Court cannot identify any real,
much less substantial, barrier to any woman’s ability to ob-
tain an abortion. And second, the Court cannot demon-
strate that any such obstacle would affect a sufficient number
of women to justify invalidating the statute on its face.
1
The Casey joint opinion makes clear that the Court should
not strike down state regulations of abortion based on the
21 The majority’s conclusion that health exceptions are required when-
ever there is any support for use of a procedure is particularly troubling
because the majority does not indicate whether an exception for physical
health only is required, or whether the exception would have to account
for “all factors—physical, emotional, psychological, familial, and the wom-
an’s age—relevant to the well being of the patient.” Doe v. Bolton, 410
U. S. 179, 192 (1973). See also Voinovich v. Women’s Medical Profes-
sional Corp., 523 U. S. 1036, 1037 (1998) (Thomas, J., joined by Rehn-
quist, C. J., and Scalia, J., dissenting from denial of certiorari).

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1014 STENBERG v. CARHART
Thomas, J., dissenting
fact that some women might face a marginally higher health
risk from the regulation. In Casey, the Court upheld a 24-
hour waiting period even though the Court credited evidence
that for some women the delay would, in practice, be much
longer than 24 hours, and even though it was undisputed that
any delay in obtaining an abortion would impose additional
health risks. Id., at 887; id., at 937 (Blackmun, J., concurring
in part, concurring in judgment in part, and dissenting in
part) (“The District Court found that the mandatory 24-hour
delay could lead to delays in excess of 24 hours, thus increas-
ing health risks”). Although some women would be able to
avoid the waiting period because of a “medical emergency,”
the medical emergency exception in the statute was limited
to those women for whom delay would create “serious risk
of substantial and irreversible impairment of a major bodily
function.” Id., at 902 (appendix to joint opinion) (internal
quotation marks omitted). Without question, there were
women for whom the regulation would impose some addi-
tional health risk who would not fall within the medical
emergency exception. The Court concluded, despite the
certainty of this increased risk, that there was no showing
that the burden on any of the women was substantial. Id.,
at 887.
The only case in which this Court has overturned a State’s
attempt to prohibit a particular form of abortion also demon-
strates that a marginal increase in health risks is not suffi-
cient to create an undue burden. In Planned Parenthood of
Central Mo. v. Danforth, 428 U. S. 52 (1976), the Court
struck down a state regulation because the State had out-
lawed the method of abortion used in 70% of abortions and
because alternative methods were, the Court emphasized,
“significantly more dangerous and critical” than the prohib-
ited method. Id., at 76.
Like the Casey 24-hour waiting period, and in contrast to
the situation in Danforth, any increased health risk to
women imposed by the partial birth abortion ban is minimal

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1015 Cite as: 530 U. S. 914 (2000)
Thomas, J., dissenting
at most. Of the 5.5% of abortions that occur after 15 weeks
(the time after which a partial birth abortion would be possi-
ble), the vast majority are performed with a D&E or induc-
tion procedure. And, for any woman with a vertex presen-
tation fetus, the vertex presentation form of intact D&E,
which presumably shares some of the health benefits of the
partial birth abortion procedure but is not covered by the
Nebraska statute, is available. Of the remaining women—
that is, those women for whom a partial birth abortion proce-
dure would be considered and who have a breech presenta-
tion fetus—there is no showing that any one faces a signifi-
cant health risk from the partial birth abortion ban. A
select committee of ACOG “could identify no circumstances
under which this procedure . . . would be the only option to
save the life or preserve the health of the woman.” App.
600 (ACOG Executive Board, Statement on Intact Dilation
and Extraction (Jan. 12, 1997)). See also Hope Clinic v.
Ryan, 195 F. 3d 857, 872 (CA7 1999) (en banc) (“ ‘There does
not appear to be any identified situation in which intact
D&X is the only appropriate procedure to induce abortion’ ”
(quoting Late Term Pregnancy Techniques, AMA Policy
H–5.982 W. D. Wis. 1999)); Planned Parenthood of Wis. v.
Doyle, 44 F. Supp. 2d, at 980 (citing testimony of Dr. Haskell
that “the D&X procedure is never medically necessary to . . .
preserve the health of a woman”), vacated, 195 F. 3d 857
(CA7 1999). And, an ad hoc coalition of doctors, including
former Surgeon General Koop, concluded that there are
no medical conditions that require use of the partial birth
abortion procedure to preserve the mother’s health. See
App. 719.
In fact, there was evidence before the Nebraska Legisla-
ture that partial birth abortion increases health risks rela-
tive to other procedures. During floor debates, a proponent
of the Nebraska legislation read from and cited several arti-
cles by physicians concluding that partial birth abortion pro-
cedures are risky. App. in Nos. 98–3245, 98–3300 (CA8),

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1016 STENBERG v. CARHART
Thomas, J., dissenting
p. 812. One doctor testifying before a committee of the Ne-
braska Legislature stated that partial birth abortion in-
volves three “very risky procedures”: dilation of the cervix,
using instruments blindly, and conversion of the fetus. App.
721 (quoting testimony of Paul Hays, M. D.).22
There was also evidence before Congress that partial birth
abortion “does not meet medical standards set by ACOG nor
has it been adequately proven to be safe nor efficacious.”
H. R. 1833 Hearing 112 (statement of Nancy G. Romer,
M. D.); see id., at 110–111.23 The AMA supported the con-
gressional ban on partial birth abortion, concluding that the
procedure is “not medically indicated” and “not good medi-
cine.” See 143 Cong. Rec. S4670 (May 19, 1997) (reprinting
a letter from the AMA to Sen. Santorum). And there was
evidence before Congress that there is “certainly no basis
upon which to state the claim that [partial birth abortion] is
a safer or even a preferred procedure.” Partial Birth Abor-
tion: The Truth, S. 6 and H. R. 929 Joint Hearing 123 (state-
ment of Curtis Cook, M. D.). This same doctor testified that
22 Use of the procedure may increase the risk of complications, including
cervical incompetence, because it requires greater dilation of the cervix
than other forms of abortion. See Epner, Jonas, & Seckinger, Late-term
Abortion, 280 JAMA 724, 726 (Aug. 26, 1998). Physicians have also sug-
gested that the procedure may pose a greater risk of infection. See
Planned Parenthood of Wis. v. Doyle, 44 F. Supp. 2d 975, 979 (WD Wis.
1999). See also Sprang & Neerhof, Rationale for Banning Abortions Late
in Pregnancy, 280 JAMA 744 (Aug. 26, 1998) (“Intact D&X poses serious
medical risks to the mother”).
23 Nebraska was entitled to rely on testimony and evidence presented to
Congress and to other state legislatures. Cf. Erie v. Pap’s A. M., 529
U. S. 277, 296–297 (2000); Renton v. Playtime Theatres, Inc., 475 U. S.
41, 51 (1986). At numerous points during the legislative debates, various
members of the Nebraska Legislature made clear that that body was
aware of, and relying on, evidence before Congress and other legislative
bodies. See App. in Nos. 98–3245, 98–3300 (CA8), pp. 846, 852–853, 878–
879, 890–891, 912–913.

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Thomas, J., dissenting
“partial-birth abortion is an unnecessary, unsteady, and po-
tentially dangerous procedure,” and that “safe alternatives
are in existence.” Id., at 122.
The majority justifies its result by asserting that a “sig-
nificant body of medical opinion” supports the view that par-
tial birth abortion may be a safer abortion procedure. Ante,
at 937. I find this assertion puzzling. If there is a “signifi-
cant body of medical opinion” supporting this procedure, no
one in the majority has identified it. In fact, it is uncon-
tested that although this procedure has been used since at
least 1992, no formal studies have compared partial birth
abortion with other procedures. 11 F. Supp. 2d, at 1112 (cit-
ing testimony of Dr. Stubblefield); id., at 1115 (citing testi-
mony of Dr. Boehm); Epner, Jonas, & Seckinger, Late-term
Abortion, 280 JAMA 724 (Aug. 26, 1998); Sprang & Neerhof,
Rationale for Banning Abortion Late in Pregnancy, 280
JAMA 744 (Aug. 26, 1998). Cf. Kumho Tire Co. v. Carmi-
chael, 526 U. S. 137, 149–152 (1999) (observing that the relia-
bility of a scientific technique may turn on whether the tech-
nique can be and has been tested; whether it has been
subjected to peer review and publication; and whether there
is a high rate of error or standards controlling its operation).
The majority’s conclusion makes sense only if the undue-
burden standard is not whether a “significant body of medi-
cal opinion” supports the result, but rather, as Justice
Ginsburg candidly admits, whether any doctor could rea-
sonably believe that the partial birth abortion procedure
would best protect the woman. Ante, at 952.
Moreover, even if I were to assume credible evidence on
both sides of the debate, that fact should resolve the undue-
burden question in favor of allowing Nebraska to legislate.
Where no one knows whether a regulation of abortion poses
any burden at all, the burden surely does not amount to a
“substantial obstacle.” Under Casey, in such a case we
should defer to the legislative judgment. We have said:

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1018 STENBERG v. CARHART
Thomas, J., dissenting
“[I]t is precisely where such disagreement exists that
legislatures have been afforded the widest latitude in
drafting such statutes. . . . [W]hen a legislature under-
takes to act in areas fraught with medical and scientific
uncertainties, legislative options must be especially
broad . . . .” Kansas v. Hendricks, 521 U. S., at 360, n. 3
(internal quotations marks omitted).
In Justice O’Connor’s words:
“It is . . . difficult to believe that this Court, without
the resources available to those bodies entrusted with
making legislative choices, believes itself competent to
make these inquiries and to revise these standards
every time the American College of Obstetricians and
Gynecologists (ACOG) or similar group revises its views
about what is and what is not appropriate medical pro-
cedure in this area.” Akron v. Akron Center for Re-
productive Health, Inc., 462 U. S., at 456 (dissenting
opinion).
See id., at 456, n. 4 (“Irrespective of the difficulty of the task,
legislatures, with their superior factfinding capabilities, are
certainly better able to make the necessary judgments than
are courts”); Webster v. Reproductive Health Services, 492
U. S., at 519 (plurality opinion) (Court should not sit as an “ex
officio medical board with powers to approve or disapprove
medical and operative practices and standards throughout
the United States (internal quotations marks omitted));
Jones v. United States, 463 U. S. 354, 365, n. 13 (1983) (“The
lesson we have drawn is not that government may not act in
the face of this [medical] uncertainty, but rather that courts
should pay particular deference to reasonable legislative
judgments”). The Court today disregards these principles
and the clear import of Casey.
2
Even if I were willing to assume that the partial birth
method of abortion is safer for some small set of women, such

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Thomas, J., dissenting
a conclusion would not require invalidating the Act, because
this case comes to us on a facial challenge. The only ques-
tion before us is whether respondent has shown that “ ‘no
set of circumstances exists under which the Act would be
valid.’ ” Ohio v. Akron Center for Reproductive Health, 497
U. S. 502, 514 (1990) (quoting Webster v. Reproductive Health
Services, supra, at 524 (O’Connor, J., concurring in part and
concurring in judgment)). Courts may not invalidate on its
face a state statute regulating abortion “based upon a
worst-case analysis that may never occur.” 497 U. S., at 514.
Invalidation of the statute would be improper even assum-
ing that Casey rejected this standard sub silentio (at least
so far as abortion cases are concerned) in favor of a so-called
“ ‘large fraction’ ” test. See Fargo Women’s Health Organi-
zation v. Schafer, 507 U. S. 1013, 1014 (1993) (O’Connor,
J., joined by Souter, J., concurring) (arguing that the “no
set of circumstances” standard is incompatible with Casey).
See also Janklow v. Planned Parenthood, Sioux Falls
Clinic, 517 U. S. 1174, 1177–1179 (1996) (Scalia, J., dissent-
ing from denial of certiorari). In Casey, the Court was pre-
sented with a facial challenge to, among other provisions, a
spousal notice requirement. The question, according to the
majority, was whether the spousal notice provision operated
as a “substantial obstacle” to the women “whose conduct it
affects,” namely, “married women seeking abortions who do
not wish to notify their husbands of their intentions and who
do not qualify for one of the statutory exceptions to the
notice requirement.” 505 U. S., at 895. The Court deter-
mined that a “large fraction” of the women in this category
were victims of psychological or physical abuse. Ibid. For
this subset of women, according to the Court, the provision
would pose a substantial obstacle to the ability to obtain an
abortion because their husbands could exercise an effective
veto over their decision. Id., at 897.
None of the opinions supporting the majority so much as
mentions the large fraction standard, undoubtedly because

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1020 STENBERG v. CARHART
Thomas, J., dissenting
the Nebraska statute easily survives it. I will assume, for
the sake of discussion, that the category of women whose
conduct Nebraska’s partial birth abortion statute might af-
fect includes any woman who wishes to obtain a safe abortion
after 16 weeks’ gestation. I will also assume (although I
doubt it is true) that, of these women, every one would be
willing to use the partial birth abortion procedure if so ad-
vised by her doctor. Indisputably, there is no “large frac-
tion” of these women who would face a substantial obstacle
to obtaining a safe abortion because of their inability to use
this particular procedure. In fact, it is not clear that any
woman would be deprived of a safe abortion by her inability
to obtain a partial birth abortion. More medically sophisti-
cated minds than ours have searched and failed to identify a
single circumstance (let alone a large fraction) in which par-
tial birth abortion is required. But no matter. The “ad hoc
nullification” machine is back at full throttle. See Thorn-
burgh v. American College of Obstetricians and Gynecolo-
gists, 476 U. S., at 814 (O’Connor, J., dissenting); Madsen
v. Women’s Health Center, Inc., 512 U. S. 753, 785 (1994)
(Scalia, J., concurring in judgment in part and dissenting
in part).
* * *
We were reassured repeatedly in Casey that not all regula-
tions of abortion are unwarranted and that the States may
express profound respect for fetal life. Under Casey, the
regulation before us today should easily pass constitutional
muster. But the Court’s abortion jurisprudence is a particu-
larly virulent strain of constitutional exegesis. And so
today we are told that 30 States are prohibited from banning
one rarely used form of abortion that they believe to border
on infanticide. It is clear that the Constitution does not
compel this result.
I respectfully dissent.