Xiulu Ruan v. United States

P R E L I M I N A R Y P R I N T
Volume 597 U. S. Part 2
Pages 450–480
OFFICIAL REPORTS
OF
T H E S U P R E M E C O U R T
June 27, 2022
REBECCA A. WOMELDORF
reporter of decisions
Page Proof Pending Publication
N O T I C E : This preliminary print is subject to formal revision before
the bound volume is published. Users are requested to notify the Reporter
of Decisions, Supreme Court of the United States, Washington, D.C. 20543,
pio@supremecourt.gov, of any typographical or other formal errors.

450 OCTOBER
TERM, 2021
Syllabus
XIULU RUAN v. UNITED STATES
certiorari
to the united states court of appeals for
the eleventh circuit
No. 20–1410. Argued March 1, 2022—Decided June 27, 2022*
Petitioners Xiulu Ruan and Shakeel Kahn are medical doctors licensed to
prescr ibe control led subst ances. Each was tried for v iolati ng 21
U. S. C. § 841, which makes it a federal crime, “[e]xcept as authorized[,]
. . . for any person knowingly or intentionally . . . to manufacture, dis-
tribute, or dispense . . . a controlled substance.” A federal regulation
authorizes registered doctors to dispense controlled substances via pre-
scription, but only if the prescription is “issued for a legitimate medical
purpose by an individual practitioner acting in the usual course of his
professional practice.” 21 CFR § 1306.04(a). At issue in Ruan's and
Kahn's trials was the mens rea required to convict under § 841 for dis-
tributing controlled substances not “as authorized.” Ruan and Kahn
each contested the jury instructions pertaining to mens rea given at
their trials, and each was ultimately convicted under § 841 for prescrib-
ing in an unauthorized manner. Their convictions were separately af-
frmed by the Courts of Appeals.
Held: Section 841's “knowingly or intentionally” mens rea applies to the
statute's “except as authorized” clause. Once a defendant meets the
burden of producing evidence that his or her conduct was “authorized,”
the Government must prove beyond a reasonable doubt that the defend-
ant know i ng ly or i ntenti ona l ly ac ted i n an unauthor i zed manner.
Pp. 457–468.
(a) Criminal law generally seeks to punish conscious wrongdoing.
Thus, when interpreting criminal statutes, the Court “start[s] from a
longstanding presumption . . . that Congress intends to require a defend-
ant to possess a culpable mental state.” Rehaif v. United States, 588
U. S. –––, –––. This culpable mental state, known as scienter, refers to
the degree of knowledge necessary to make a person criminally respon-
sible for his or her acts. See ibid. The presumption of scienter applies
even when a statute does not include a scienter provision, and when a
statute does “includ[e] a general scienter provision,” “the presumption
applies with equal or greater force” to the scope of that provision. Ibid.
The Court has accordingly held that a word such as “knowingly” mod-
*Together with No. 21–5261, Kahn v. United States, on certiorari to the
United States Court of Appeals for the Tenth Circuit.
Page Proof Pending Publication

Cite
as: 597 U. S. 450 (2022)
451
Syllabus
ifes not only the words directly following it, but also those other statu-
tory
terms that “separate wrongful from innocent acts.” Id., at –––.
Here, § 841 contains a general scienter provision—“knowingly or in-
tentionally.” And in § 841 prosecutions, authorization plays a “crucial”
role in separating innocent conduct from wrongful conduct. United
States v. X-Citement Video, Inc., 513 U. S. 64, 73. Moreover, the regu-
latory language defning an authorized prescription is “ambiguous” and
“open to varying constructions,” Gonzales v. Oregon, 546 U. S. 243, 258,
meaning that prohibited conduct (issuing invalid prescriptions) is
“often diffcult to distinguish” from acceptable conduct (issuing valid
prescriptions). United States v. United States Gypsum Co., 438 U. S.
422, 441. A strong scienter requirement helps reduce the risk of “over-
deterrence,” i. e., punishing conduct that lies close to, but on the permis-
sible side of, the criminal line. Ibid.
The statutory provisions at issue here are also not the kind to which
the Court has held the presumption of scienter does not apply. Section
841 does not defne a regulatory or public welfare offense that carries
only minor penalties. Cf. Rehaif, 588 U. S., at –––; Staples v. United
States, 511 U. S. 600, 618–619. Nor is the “except as authorized” clause
a jurisdictional provision. Cf. Rehaif, 588 U. S., at –––. Pp. 457–460.
(b) Analogous precedent reinforces the Court's conclusion here. In
Liparota v. United States, 471 U. S. 419, United States v. X-Citement
Video, 513 U. S. 64, and Rehaif v. United States, 588 U. S. –––, the Court
interpreted statutes containing a general scienter provision (“know-
ingly”), and considered what mental state applied to a statutory clause
that did not immediately follow the “knowingly” provision. In all three
cases, the Court held that “knowingly” modifed the statutory clause in
question because that clause played a critical role in separating a de-
fendant's wrongful from innocent conduct. See Liparota, 471 U. S., at
426; X-Citement Video, 513 U. S., at 72–73; Rehaif, 588 U. S., at –––. As
in those cases, the Court today concludes that § 841's mens rea applies
to the “[e]xcept as authorized” clause, which serves to separate a defend-
ant's wrongful from proper conduct. Pp. 460–461.
(c) Neither the Government's nor the concurrence's contrary argu-
ments are convincing. First, the Government and the concurrence cor-
rectly note that the statutory clauses in the cases just described set
forth elements of an offense. Here, the Government and the concur-
rence say, § 841's “[e]xcept as authorized” clause does not set forth an
element of the offense. In support, they point to a separate statutory
provision—§ 885. Section 885 says that the Government need not “neg-
ative any exemption or exception . . . in any complaint, information,
indictment, or other pleading or in any trial,” and that “the burden of
going forward with the evidence with respect to any such exemption or
Page Proof Pending Publication

Page Proof Pending Publication
452 XIUL
U RUAN v. UNITED STATES
Syllabus
exception shall be upon the person claiming its beneft,” not upon the
prosecuti
on. But even assuming that lack of authorization is unlike an
element in these two ways, § 885 has little or nothing to do with scienter
requirements. Section 885 simply absolves the Government of having
to allege, in an indictment, the inapplicability of every statutory excep-
tion in each Controlled Substances Act prosecution. Section 885 also
shifts the burden of production—but not the burden of persuasion—
regarding statutory exceptions to the defendant, thereby relieving the
Government of having to disprove, at the outset of every prosecution,
the inapplicability of all exceptions.
Section 885 thus does not provide a basis for inferring that Congress
intended to do away with, or weaken, ordinary and longstanding scien-
ter requirements. At the same time, the factors discussed above—the
language of § 841; the crucial role authorization plays in distinguishing
morally blameworthy conduct from socially necessary conduct; the seri-
ous nature of the crime and its penalties; and the vague, highly general
regulatory language defning the scope of prescribing authority—all
support applying normal scienter principles to the “except as author-
ized” clause. And the Government does not deny that, once a defendant
satisfes his burden of production under § 885 by invoking the authoriza-
tion exception, the Government must then prove lack of authorization
by satisfying the ordinary criminal law burden of proof—beyond a rea-
sonable doubt.
The Government also offers a substitute mens rea standard. Instead
of applying the statute's “knowingly or intentionally” language to the
authorization clause, the Government instead asserts that the statute
implicitly contains an “objectively reasonable good-faith effort” or “ob-
jective honest-effort standard.” Brief for United States 16–17. But
§ 841 uses the words “knowingly or intentionally,” not “good faith,” “ob-
jectively,” “reasonable,” or “honest effort.” And the Government's
standard would turn a defendant's criminal liability on the mental state
of a hypothetical “reasonable” doctor, rather than on the mental state
of the defendant himself or herself. The Court has rejected analogous
suggestions in other criminal contexts. See Elonis v. United States,
575 U. S. 723. And the Government is wrong to assert that the Court
effectively endorsed its honest-effort standard in United States v.
Moore, 423 U. S. 122, as that case did not address mens rea at all. Nor
does United States v. Yermian, 468 U. S. 63, support the Government
here, as that case dealt with a jurisdictional clause, to which the pre-
sumption of scienter does not apply.
Finally, the Government argues that requiring it to prove that a doc-
tor knowingly or intentionally acted not “as authorized” will allow bad-
apple doctors to escape liability by claiming idiosyncratic views about

Cite
as: 597 U. S. 450 (2022)
453
Syllabus
their prescribing authority. But the Court has often rejected this kind
of
argument, see, e. g., Rehaif, 588 U. S., at –––, and does so again here.
Pp. 462–467.
(d) The Court of Appeals in both cases evaluated the jury instructions
relating to mens rea under an incorrect understanding of § 841's scienter
requirements. On remand, those courts may address whether the in-
structions complied with the mens rea standard set forth here, as well
as whether any instructional error was harmless. P. 467.
966 F. 3d 1101 and 989 F. 3d 806, vacated and remanded.
Breyer, J. delivered the opinion of the Court, in which Roberts, C. J.,
and Sotomayor, Kagan, Gorsuch, and Kavanaugh, JJ., joined. Alito,
J., fled an opinion concurring in the judgment, in which Thomas, J., joined,
and in which Barrett, J., joined as to Parts I–A, I–B, and II, post, p. 468.
Lawrence S. Robbins argued the cause for petitioner in
No. 20 –1410. With h i m on the br iefs were Wi ll i am J.
Trunk, Jeffrey C. Thalhofer, Carolyn M. Forstein, and Leslie
C. Esbrook.
Beau B. Brindley argued the cause for petitioner in
No. 21–5261. With him on the briefs was Blair T. Westover.
Deputy Solicitor General Feigin argued the cause for the
United States in both cases. With him on the brief were
Solicitor General Prelogar, Assistant Attorney General Po-
lite, Nicole Frazer Reaves, Joshua K. Handell, and David
M. Lieberman.†
†Briefs of amici curiae urging reversal in both cases were fled for
Compassion & Choices by Robert A. Koch, Steven M. Wilker, and Kevin
Díaz; for the National Association of Criminal Defense Lawyers by Jeffrey
S. Beelaert and David Oscar Markus; and for Anmol Singh Kamra by
Peter Golberger and Pamela A. Wilk. A brief of amicus curiae urging
vacatur was fled in both cases for the National Pain Advocacy Center by
H. Christopher Bartolomucci and Kenneth A. Klukowski.
Briefs of amici curiae urging reversal in No. 20–1410 were fled for the
Association of American Physicians and Surgeons et al. by Andrew L.
Schlafy; for the Cato Institute by Clark Neily; for Professors of Health
Law and Policy by Jennifer D. Oliva; and for Stephen J. Ziegler et al. by
Ronald W. Chapman II.
Briefs of amici curiae were fled in No. 20–1410 for the Due Process
Institute by Andrew D. Prins and Shana-Tara O'Toole; for the Pacifc
Page Proof Pending Publication

454 XIUL
U RUAN v. UNITED STATES
Opinion of the Court
Justice Breyer delivered the opinion of the Court.
A
provision of the Controlled Substances Act, codifed at
21 U. S. C. § 841, makes it a federal crime, “[e]xcept as au-
thorized[,] . . . for any person knowingly or intentionally . . .
to manufacture, distribute, or dispense . . . a controlled sub-
stance,” such as opioids. 84 Stat. 1260, 21 U. S. C. § 841(a)
(emphasis added). Registered doctors may prescribe these
substances to their patients. But, as provided by regula-
tion, a prescription is only authorized when a doctor issues
it “for a legitimate medical purpose . . . acting in the usual
course of his professional practice.” 21 CFR § 1306.04(a)
(2021).
In each of these two consolidated cases, a doctor was con-
victed under § 841 for dispensing controlled substances not
“as authorized.” The question before us concerns the state
of mind that the Government must prove to convict these
doctors of violating the statute. We hold that the statute's
“knowingly or intentionally” mens rea applies to authoriza-
tion. After a defendant produces evidence that he or she
was authorized to dispense controlled substances, the Gov-
ernment must prove beyond a reasonable doubt that the de-
fendant knew that he or she was acting in an unauthorized
manner, or intended to do so.
I
The question we face concerns § 841's exception from the
general prohibition on dispensing controlled substances con-
tained in the phrase “[e]xcept as authorized.” In particular,
the question concerns the defendant's state of mind. To
prove that a doctor's dispensation of drugs via prescription
falls within the statute's prohibition and outside the authori-
Legal Foundation by Oliver J. Dun ford and Caleb Kruckenberg; and for
Physicians Against Abuse by Sebastian Ohanian.
Briefs of amici curiae were fled in both cases for the Chamber of Com-
merce of the United States of America by Michael R. Dreeben and Andrew
R. Varcoe; and for the National Association of Chain Drug Stores by
Trevor S. Cox, Torsten M. Kracht, and Cameron L. Davis.
Page Proof Pending Publication

Cite
as: 597 U. S. 450 (2022)
455
Opinion of the Court
zation exception, is it suffcient for the Government to prove
that
a prescription was in fact not authorized, or must the
Government prove that the doctor knew or intended that the
prescription was unauthorized?
Petitioners Xiulu Ruan and Shakeel Kahn are both doctors
who actively practiced medicine. They both possessed li-
censes permitting them to prescribe controlled substances.
The Government separately charged them with unlawfully
dispensing and distr ibuting dr ugs in vi olati on of § 841.
Each proceeded to a jury trial, and each was convicted of
the charges.
At their separate trials, Ruan and Kahn argued that their
dispensation of drugs was lawful because the drugs were dis-
pensed pursuant to valid prescriptions. As noted above, a
regulation provides that, “to be effective,” a prescription
“must be issued for a legitimate medical purpose by an indi-
vidual practitioner acting in the usual course of his profes-
sional practice.” 21 CFR § 1306.04(a). We assume, as did
the courts below and the parties here, that a prescription is
“authorized” and therefore lawful if it satisfes this standard.
At Ruan's and Kahn's trials, the Government argued that the
doctors' prescriptions failed to comply with this standard.
The doctors argued that their prescriptions did comply, and
that, even if not, the doctors did not knowingly deviate or
intentionally deviate from the standard.
Ruan, for example, asked for a jury instruction that would
have required the Government to prove that he subjectively
knew that his prescriptions fell outside the scope of his pre-
scribing authority. The District Court, however, rejected
this request. The court instead set forth a more objective
st andard, i nstr uc ti ng the jury that a doc tor ac ts law-
fully when he prescribes “in good faith as part of his medi-
cal treatment of a patient in accordance with the standard
of medical practice generally recognized and accepted in
the United States.” App. to Pet. for Cert. in No. 20–1410,
p. 139a. The court further instructed the jury that a doctor
Page Proof Pending Publication

456 XIUL
U RUAN v. UNITED STATES
Opinion of the Court
violates § 841 when “the doctor's actions were either not for
a
legitimate medical purpose or were outside the usual
course of professional medical practice.” Ibid. The jury
convicted Ruan, and the trial court sentenced him to over 20
years in prison and ordered him to pay millions of dollars in
restitution and forfeiture.
The Eleventh Circuit affrmed Ruan's convictions. See
966 F. 3d 1101, 1120, 1166–1167 (2020). The appeals court
held that a doctor's “subjectiv[e] belie[f] that he is meeting
a patient's medical needs by prescribing a controlled sub-
stance” is not a “complete defense” to a § 841 prosecution.
Id., at 1167. Rather, the court said, “ `[w]hether a defendant
acts in the usual course of his professional practice must be
evaluated based on an objective standard, not a subjective
standard.' ” Id., at 1166 (quoting United States v. Joseph,
709 F. 3d 1082, 1097 (CA11 2013); emphasis added; alteration
in original).
Kahn's trial contained similar disagreements over the
proper mens rea instructions. Ultimately, the District
Court instructed the jury that it should not convict if it found
that Kahn acted in “good faith,” defned as “an attempt to
act in accordance with what a reasonable physician should
believe to be proper medical practice.” App. in No. 21–5261,
p. 486. The court added that to fnd “good faith,” the jury
must conclude that Kahn “acted in an honest effort to pre-
scribe for patients' medical conditions in accordance with
generally recognized and accepted standards of practice.”
Ibid. The court also told the jury that “good faith” was a
“complete defense” because it “would be inconsistent with
knowingly and intentionally distributing and/or dispensing
controlled substances outside the usual course of professional
practice and without a legitimate medical purpose.” Ibid.
The jury convicted Kahn of the § 841 charges, and he was
sentenced to 25 years in prison.
The Tenth Circuit affrmed Kahn's convictions. See 989
F. 3d 806, 812, 824–826 (2021). In doing so, the court held
Page Proof Pending Publication

Cite
as: 597 U. S. 450 (2022)
457
Opinion of the Court
that to convict under § 841, the Government must prove that
a
doctor “either: (1) subjectively knew a prescription was
issued not for a legitimate medical purpose; or (2) issued a
prescription that was objectively not in the usual course of
professional practice.” Id., at 825.
Both Ruan and Kahn fled petitions for certiorari. We
granted the petitions and consolidated the cases to consider
what mens rea applies to § 841's authorization exception.
II
As we have said, § 841 makes it unlawful, “[e]xcept as au-
thorized[,] . . . for any person knowingly or intentionally . . .
to manufacture, distribute, or dispense . . . a controlled sub-
stance.” We now hold that § 841's “knowingly or intention-
ally” mens rea applies to the “except as authorized” clause.
This means that once a defendant meets the burden of pro-
ducing evidence that his or her conduct was “authorized,”
the Government must prove beyond a reasonable doubt that
the defendant knowingly or intentionally acted in an unau-
thor i zed manner. Our conclusi on rests upon severa l
considerations.
A
First, as a general matter, our criminal law seeks to punish
the “ `vicious will.' ” Morissette v. United States, 342 U. S.
246, 251 (1952); see also id., at 250, n. 4 (quoting F. Sayre,
Cases on Criminal Law, p. xxxvi (R. Pound ed. 1927)). With
few exceptions, “ `wrongdoing must be conscious to be crimi-
nal.' ” Elonis v. United States, 575 U. S. 723, 734 (2015)
(quoting Morissette, 342 U. S., at 252). Indeed, we have said
that consciousness of wrongdoing is a principle “as universal
and persistent in mature systems of [criminal] law as belief
in freedom of the human will and a consequent ability and
duty of the normal individual to choose between good and
evil.” Id., at 250.
Consequently, when we interpret criminal statutes, we
normally “start from a longstanding presumption, traceable
Page Proof Pending Publication

458 XIUL
U RUAN v. UNITED STATES
Opinion of the Court
to the common law, that Congress intends to require a de-
fendant
to possess a culpable mental state.” Rehaif v.
United States, 588 U. S. –––, ––– (2019). We have referred
to this culpable mental state as “scienter,” which means the
degree of knowledge necessary to make a person criminally
responsible for his or her acts. See ibid.; Black's Law Dic-
tionary 1613 (11th ed. 2019); Morissette, 342 U. S., at 250–
252.
Applying the presumption of scienter, we have read into
criminal statutes that are “silent on the required mental
state”—meaning statutes that contain no mens rea provision
whatsoever—“ `that mens rea which is necessary to separate
wrongful conduct from “otherwise innocent conduct.” ' ”
Elonis, 575 U. S., at 736 (quoting Carter v. United States,
530 U. S. 255, 269 (2000); emphasis added). Unsurprisingly,
given the meaning of scienter, the mens rea we have read
into such statutes is often that of knowledge or intent. See,
e. g., Staples v. United States, 511 U. S. 600, 619 (1994);
United States v. United States Gypsum Co., 438 U. S. 422,
444–446 (1978).
And when a statute is not silent as to mens rea but instead
“includes a general scienter provision,” “the presumption
applies with equal or greater force” to the scope of that pro-
vision. Rehaif, 588 U. S., at ––– (emphasis added). We
have accordingly held that a word such as “knowingly” mod-
ifes not only the words directly following it, but also those
other statutory terms that “separate wrongful from innocent
acts.” Id., at –––; United States v. X-Citement Video, Inc.,
513 U. S. 64, 72 (1994); Liparota v. United States, 471 U. S.
419, 426 (1985).
Section 841 contains a general scienter provision—“know-
ingly or intentionally.” And in § 841 prosecutions, a lack of
authorization is often what separates wrongfulness from in-
nocence. Defendants who produce evidence that they are
“authorized” to dispense controlled substances are often doc-
Page Proof Pending Publication

Cite
as: 597 U. S. 450 (2022)
459
Opinion of the Court
tors dispensing drugs via prescription. We normally would
not
view such dispensations as inherently illegitimate; we
expect, and indeed usually want, doctors to prescribe the
medications that their patients need. In § 841 prosecutions,
then, it is the fact that the doctor issued an unauthorized
prescription that renders his or her conduct wrongful, not
the fact of the dispensation itself. In other words, authori-
zation plays a “crucial” role in separating innocent conduct—
and, in the case of doctors, socially benefcial conduct—from
wrongful conduct. X-Citement Video, 513 U. S., at 73.
Applying § 841's “knowingly or intentionally” mens rea to
the authorization clause thus “helps advance the purpose of
scienter, for it helps to separate wrongful from innocent
acts.” Rehaif, 588 U. S., at –––; see also X-Citement Video,
513 U. S., at 72–73.
In addition, the regulatory language defning an author-
ized prescription is, we have said, “ambiguous,” written in
“generalit[ies], susceptible to more precise defnition and
open to varying constructions.” Gonzales v. Oregon, 546
U. S. 243, 258 (2006); see id., at 257 (regulation “gives little
or no instruction on” major questions); see also 21 CFR
§ 1306.04(a) (regulation defning “effective” prescription as
one “issued for a legitimate medical purpose by an individual
practitioner acting in the usual course of his professional
practice”). The conduct prohibited by such language (issu-
ing invalid prescriptions) is thus “often diffcult to distin-
guish from the gray zone of socially acceptable . . . conduct”
(issuing valid prescriptions). United States Gypsum, 438
U. S., at 441. A strong scienter requirement helps to dimin-
ish the risk of “overdeterrence,” i. e., punishing acceptable
and benefcial conduct that lies close to, but on the permissi-
ble side of, the criminal line. Ibid.
The statutory provisions at issue here are also not the kind
that we have held fall outside the scope of ordinary scienter
requirements. Section 841 does not defne a regulatory or
Page Proof Pending Publication

460 XIUL
U RUAN v. UNITED STATES
Opinion of the Court
public welfare offense that carries only minor penalties. Cf.
Rehai
f, 588 U. S., at –––; Staples, 511 U. S., at 606. Rather,
§ 841 imposes severe penalties upon those who violate it, in-
cluding life imprisonment and fnes up to $1 million. See
§ 841(b)(1)(C); see generally § 841(b). Such severe penalties
counsel in favor of a strong scienter requirement. See Sta-
ples, 511 U. S., at 618–619 (noting that “a severe penalty is a
further factor tending to suggest that . . . the usual presump-
tion that a defendant must know the facts that make his con-
duct illegal should apply”); United States Gypsum, 438 U. S.,
at 442, n. 18.
Nor is the “except as authorized” clause a jurisdictional
provision, to which the presumption of scienter would not
apply. Cf. Rehaif, 588 U. S., at –––; United States v. Yer-
mian, 468 U. S. 63, 68–69 (1984). To the contrary, and as we
have explained, a lack of authorization is often the critical
thing distinguishing wrongful from proper conduct.
B
Analogous precedent reinforces our conclusion. In Lipar-
ota, we interpreted a statute penalizing anyone who “ `know-
ingly uses [food stamps] in any manner not authorized by' ”
statute. 471 U. S., at 420. We held that “knowingly” modi-
fed both the “use” of food stamps element and the element
that the use be “not authorized.” Id., at 423, 433. We ap-
plied “knowingly” to the authorization language even though
Congress had not “explicitly and unambiguously” indicated
that it should so apply. Id., at 426. But if knowingly did
not modify the fact of nonauthorization, we explained, the
statute “would . . . criminalize a broad range of apparently
innocent conduct.” Ibid.
Similarly, in X-Citement Video, we interpreted a statute
penalizing anyone who “ `knowingly transports' ” or “ `know-
ingly receives' ” videos “ `involv[ing] the use of a minor en-
gaging in sexually explicit conduct.' ” 513 U. S., at 68. We
held that “knowingly” applied not only to the element of
Page Proof Pending Publication

Cite
as: 597 U. S. 450 (2022)
461
Opinion of the Court
transporting or receiving videos but also to the elemental
fac
t that the videos involve “the use of a minor.” Id., at
66. We recognized that this was not “the most grammatical
reading of the statute.” Id., at 70. But, we explained,
“the age of the performers is the crucial element separating
legal innocence from wrongful conduct,” for possessing sex-
ually explicit videos involving nonminors is protected First
Amendment activity. Id., at 72–73.
Finally, in Rehaif, we interpreted a statutory scheme in
which one statutory subsection provided penalties for any-
one who “knowingly violates” a separate subsection. 588
U. S., at ––– – –––. This latter subsection made it “unlawful”
for people with certain statuses (i. e., being a felon or being
in the country unlawfully) to possess a gun. Ibid. We held
that the frst subsection's “knowingly” language applied to
the status element in the second subsection. Id., at –––.
To convict under the statute, then, the Government had to
prove that a defendant knew he had one of the listed sta-
tuses. Ibid. “Without knowledge of that status,” we rea-
soned, “the defendant may well lack the intent needed to
make his behavior wrongful,” because “[a]ssuming compli-
ance with ordinary licensing requirements, the possession of
a gun can be entirely innocent.” Id., at –––.
Like the statutes at issue in these cases, the statute here
contains a scienter provision. Section 841 states: “Except
as authorized by this subchapter, it shall be unlawful for any
person knowingly or intentionally . . . to manufacture, dis-
tribute, or dispense . . . a controlled substance.” (Emphasis
added.) Like those three cases, the question here concerns
the mental state that applies to a statutory clause (“[e]xcept
as authorized”) that does not immediately follow the scienter
provision. Like the three cases, the statutory clause in
question plays a critical role in separating a defendant's
wrongful from innocent conduct. And, like the Court in
those cases, we conclude that the statute's mens rea applies
to that critical clause.
Page Proof Pending Publication

462 XIUL
U RUAN v. UNITED STATES
Opinion of the Court
III
W
e are not convinced by the Government's arguments to
the contrary. First, the Government correctly points out,
and the concurrence emphasizes, that the statutory language
at issue in the cases we have just described set forth ele-
ments of the offense. Here, the Government and the con-
currence say, the “except as authorized” clause does not set
forth an element. See, e. g., post, at 470–473 (Alito, J., con-
curring in judgment).
The Government and the concurrence point to two ways
in which the “except as authorized” clause is unlike an ele-
ment, both of which rely on a different provision of the Con-
trolled Substances Act—§ 885. Section 885 says that the
Government need not “negative”—i. e., refute—“any exemp-
tion or exception . . . in any complaint, information, indict-
ment, or other pleading.” This means that, in a prosecution
under the Controlled Substances Act, the Government need
not refer to a lack of authorization (or any other exemption
or exception) in the criminal indictment. Cf. United States
v. Resendiz-Ponce, 549 U. S. 102, 108 (2007) (criminal indict-
ment must set forth all elements of the charged crime).
Section 885 also says that the Government need not “nega-
tive any exemption or exception . . . in any trial,” and that
“the burden of going forward with the evidence with respect
to any such exemption or exception shall be upon the person
claiming its beneft,” not upon the prosecution. Cf. Patter-
son v. New York, 432 U. S. 197, 210 (1977) (Government bears
burden of proving all elements of charged offense).
But even assuming that lack of authorization is unlike an
element for the two purposes that § 885 sets forth, those two
purposes have little or nothing to do with scienter require-
ments. The frst has to do with the indictment. It simply
says that the Government need not set forth in an indictment
a lack of authorization, or otherwise allege that a defendant
does not fall within the many exceptions and exemptions
that the Controlled Substances Act contains. The Act ex-
Page Proof Pending Publication

Cite
as: 597 U. S. 450 (2022)
463
Opinion of the Court
cepts, for example, licensed professionals such as dentists,
veter
inarians, scientifc investigators, and pharmacists from
the prohibition on dispensing controlled substances. See 21
U. S. C. § 802(21). The Act also excepts employees of drug
manufacturers, common carriers, and people with sick fam-
ily members or pets from the prohibition on possessing
controlled substances. See §§ 802(27), 822(c). Section 885
merely absolves the Government of having to allege, in an
indictment, the inapplicability of every statutory exception
in each Controlled Substances Act prosecution.
Section 885's second purpose refers only to “the burden of
going forward with the evidence,” i. e., the burden of produc-
tion. See Black's Law Dictionary, at 244. It says nothing
regarding the distinct issue of the burden of persuasion—
i. e., the burden of proving a lack of authorization. Cf. Di-
rector, Offce of Workers' Compensation Programs v. Green-
wich Collieries, 512 U. S. 267, 274 (1994) (“our opinions con-
sistently distinguis[h] between burden of proof, which we
defned as burden of persuasion, and . . . the burden of pro-
duction or the burden of going forward with the evidence”);
see also Schaffer v. Weast, 546 U. S. 49, 56 (2005). Section
885 can thus be understood as providing a presumptive de-
vice, akin to others we have recognized in the criminal con-
text, which “merely shift[s] the burden of production to the
defendant, following the satisfaction of which the ultimate
burden of persuasion returns to the prosecution.” County
Court of Ulster Cty. v. Allen, 442 U. S. 140, 157–158, n. 16
(1979); see Parker v. Matthews, 567 U. S. 37, 42, n. 1 (2012)
(per curiam). Contrary to the concurrence's assertion, see
post, at 475–477, the differences between these two burdens
and the use of procedural mechanisms to shift one burden
but not the other are well established. See, e. g., 29 Am.
Jur. 2d Evidence § 207, p. 246 (2019) (“due process does not
prohibit the use of a . . . procedural device that shifts to a
defendant the burden of producing some evidence contesting
a fact that may otherwise be inferred, provided the prosecu-
Page Proof Pending Publication

Page Proof Pending Publication
464 XIUL
U RUAN v. UNITED STATES
Opinion of the Court
tion retains the ultimate burden of proof ”); 1 W. LaFave,
Subst
antive Criminal Law § 1.8(a), p. 102 (3d ed. 2018) (simi-
lar). In a § 841 prosecution, then, once the defendant satis-
fes the initial burden of production by producing evidence of
authorization, the burden of proving a lack of authorization
shifts back to the Government. And, as with § 885's indict-
ment-related purpose, § 885's burden-related purpose simply
relieves the Government from having to disprove, at the out-
set of every Controlled Substances Act prosecution, every
exception in the statutory scheme.
Section 885 thus does not provide a basis for inferring that
Congress intended to do away with, or weaken, ordinary and
longstanding scienter requirements. At the same time, the
language of § 841 (which explicitly includes a “knowingly or
intentionally” provision); the crucial role authorization (or
lack thereof ) plays in distinguishing morally blameworthy
conduct from socially necessary conduct; the serious nature
of the crime and its penalties; and the vague, highly general
language of the regulation defning the bounds of prescribing
authority all support applying normal scienter principles to
the “except as authorized” clause. That statutory require-
ment, while differing from an element in some respects, is
suffciently like an element in respect to the matter at issue
here as to warrant similar legal treatment.
And the Government does not deny that, once a defendant
claims that he or she falls within the authorization exception
and the burden shifts back to the Government, the Govern-
ment must prove a lack of authorization by satisfying the
ordinary criminal law burden of proof—beyond a reasonable
doubt. See Brief for United States 26; Tr. of Oral Arg. 50–
51; see also id., at 62–65. But see post, at 477 (concurrence
suggesting, contrary to the position advanced by all parties
to these cases, that the Government need only prove lack of
authorization by a preponderance of the evidence). Once
the defendant meets h is or her burden of produc ti on,

Cite
as: 597 U. S. 450 (2022)
465
Opinion of the Court
then, the Government must prove lack of authorization be-
yond
a reasonable doubt.
Resisting the “knowingly or intentionally” standard, the
Government instead offers a substitute mens rea standard.
The Government says that rather than simply apply the stat-
ute's “knowingly or intentionally” language to the authori-
zati on clause, we shou ld read the st atute as i mpl icitly
containing an “objectively reasonable good-faith effort” or
“objective honest-effort standard.” Brief for United States
16–17; cf. post, at 479 (concurrence arguing that doctors can
defend against a § 841 prosecution by proving that they
have “act[ed] in subjective good faith in prescribing drugs”).
That is to say, once a defendant meets his or her burden of
production, the Government can convict “by proving beyond
a reasonable doubt that [the defendant] did not even make
an objectively reasonable attempt to ascertain and act within
the bounds of professional medicine.” Brief for United
States 16.
We are not convinced. For one thing, § 841, like many
criminal statutes, uses the familiar mens rea words “know-
ingly or intentionally.” It nowhere uses words such as
“good faith,” “objectively,” “reasonable,” or “honest effort.”
For another, the Government's standard would turn a de-
fendant's criminal liability on the mental state of a hypotheti-
cal “reasonable” doctor, not on the mental state of the de-
fendant himself or herself. Cf. id., at 24 (Government
arguing that “a physician can violate Section 841(a) when
he makes no objectively reasonable attempt to conform his
conduct to something that his fellow doctors would view as
medical care” (emphasis added)).
We have rejected analogous suggestions in other criminal
contexts. In Elonis, for example, we considered the mental
state applicable to a statute that criminalized threatening
communications but contained no explicit mens rea require-
ment. 575 U. S., at 732. The Government argued that the
Page Proof Pending Publication

Page Proof Pending Publication
466 XIUL
U RUAN v. UNITED STATES
Opinion of the Court
statute required proof that a reasonable person would fnd
the
communications threatening. Id., at 738–739. But, we
said, “[h]aving liability turn on whether a `reasonable per-
son' regards the communication as a threat—regardless of
what the defendant thinks—reduces culpability on the all-
important element of the crime to negligence.” Id., at 738
(some internal quotation marks omitted). “[A]nd,” we em-
phasized, “we `have long been reluctant to infer that a negli-
gence standard was intended in criminal statutes.' ” Ibid.
(quoting Rogers v. United States, 422 U. S. 35, 47 (1975) (Mar-
shall, J., concurring)). We believe the same of the Govern-
ment's proposed standard here.
The Government asserts that we held to the contrary, and
“effectively endorsed” its honest-effort standard, in United
States v. Moore, 423 U. S. 122 (1975). Brief for United
States 26. But the question in Moore was whether doctors
could ever be held criminally liable under § 841. 423 U. S.,
at 124. Moore did not directly address the issue before us
here regarding the mens rea required to convict under the
statute.
Further, the Government, citing Yermian, notes that the
authorization clause precedes the words “knowingly or in-
tentionally.” And, the Government argues, grammatically
speaking, that fact prevents the latter mens rea provision
from modifying the former clause. See Brief for United
States 24–25. But Yermian based its holding on the fact
that the clause preceding the mens rea provision set forth a
jurisdictional criteria, which is typically not subject to a sci-
enter requirement. 468 U. S., at 68–69; see also Rehaif, 588
U. S., at –––. Yermian did not base its holding on the gram-
matical positioning of the statutory language.
Finally, the Government argues that requiring it to prove
that a doctor knowingly or intentionally acted not as author-
ized will allow bad-apple doctors to escape liability by claim-
ing idiosyncratic views about their prescribing authority.
See, e. g., Brief for United States 33. This kind of argument,
however, can be made in many cases imposing scienter re-

Page Proof Pending Publication
Cite
as: 597 U. S. 450 (2022)
467
Opinion of the Court
quirements, and we have often rejected it on bases similar
to
those we have set forth in Part II of this opinion. See,
e. g., Rehaif, 588 U. S., at –––; Liparota, 471 U. S., at 433–
434.
We do the same here. The Government, of course, can
prove knowledge of a lack of authorization through circum-
stantial evidence. See ibid. And the regulation defning
the scope of a doctor's prescribing authority does so by refer-
ence to objective criteria such as “legitimate medical pur-
pose” and “usual course” of “professional practice.” 21 CFR
§ 1306.04(a); see Gonzales, 546 U. S., at 285 (Scalia, J., dissent-
ing) (“The use of the word `legitimate' connotes an objective
standard of `medicine' ”); Moore, 423 U. S., at 141–142 (de-
scribing Congress' intent “to confne authorized medical
practice within accepted limits” (emphasis added)). As we
have said before, “the more unreasonable” a defendant's “as-
serted beliefs or misunderstandings are,” especially as meas-
ured against objective criteria, “the more likely the jury . . .
will fnd that the Government has carried its burden of prov-
ing knowledge.” Cheek v. United States, 498 U. S. 192, 203–
204 (1991). But the Government must still carry this bur-
den. And for purposes of a criminal conviction under § 841,
this requires proving that a defendant knew or intended that
his or her conduct was unauthorized.
IV
The Government argues that we should affrm Ruan's and
Kahn's convictions because the jury instructions at their
trials conveyed the requisite mens rea. Alternatively, the
Government argues that any instructional error was harm-
less. But the Court of Appeals in both cases evaluated the
jury instructions under an incorrect understanding of § 841's
scienter requirements. We decline to decide in the frst in-
stance whether the instructions complied with the standard
we have set forth today. Cf. Rehaif, 588 U. S., at –––. We
leave that and any harmlessness questions for the courts to
address on remand.

468 XIUL
U RUAN v. UNITED STATES
Alito, J., concurring in judgment
***
W
e conclude that § 841's “knowingly or intentionally”
mens rea applies to the “except as authorized” clause. This
means that in a § 841 prosecution in which a defendant meets
his burden of production under § 885, the Government must
prove beyond a reasonable doubt that the defendant know-
ingly or intentionally acted in an unauthorized manner. We
vacate the judgments of the Courts of Appeals below and
remand the cases for further proceedings consistent with
this opinion.
It is so ordered.
Justice Alito, with whom Justice Thomas joins, and
with whom Justice Barrett joins as to Parts I–A, I–B,
and II, concurring in the judgment.
In criminal law, the distinction between the elements of an
offense and an affrmative defense is well-known and impor-
tant. In these cases, however, the Court recognizes a new
hybrid that has some characteristics of an element and some
characteristics of an affrmative defense. The consequences
of this innovation are hard to foresee, but the result may
well be confusi on and disruption. That risk is entirely
unnecessary.
We granted certiorari in these cases to decide whether a
physician may be convicted of dispensing or distributing
drugs by prescription under a provision of the Controlled
Substances Act of 1970 (CSA), 21 U. S. C. § 841(a), if he or
she believed in good faith that the prescription was within
the course of professional practice. In my view, there is a
straightforward answer to this question. The CSA contains
an exception for prescriptions issued in the course of profes-
sional practice, and this exception is a carry-over from the
CSA's predecessor, the Harrison Narcotics Act of 1914, 38
Stat. 785. In interpreting the Harrison Act, this Court held
that a registered physician acts “in the course of his profes-
sional practice” when the physician writes prescriptions “in
Page Proof Pending Publication

Page Proof Pending Publication
Cite
as: 597 U. S. 450 (2022)
469
Alito, J., concurring in judgment
good faith.” Linder v. United States, 268 U. S. 5, 17–18
(1925).
I would hold that this rule applies under the CSA
and would therefore vacate the judgments below and remand
for further proceedings.
The Court declines to adopt this approach and instead
takes a radical new course. It holds that the mental state
expressed by the terms “knowingly or intentionally” in
§ 841(a) applies to the provision's “[e]xcept as authorized”
proviso. It bases this conclusion not on anything in the lan-
guage of the CSA, but instead on the “presumption, trace-
able to the common law, that Congress intends to require
a defendant to possess a culpable mental state.” Rehaif v.
United States, 588 U. S. –––, ––– (2019).
The Court's analysis rests on an obvious conceptual mis-
take. A culpable mental state—or, to use the traditional
Latin term, “mens rea”—is the mental state an accused must
have in relation to the elements of an offense. But the au-
thorizations in the CSA that excuse acts that are otherwise
unlawful under § 841(a) are not elements of the offenses cre-
ated by that provision. They are affrmative defenses.
The presumption that elements must be accompanied by a
culpable mental state—which I will call “the mens rea
canon”—provides no guidance on what a defendant must
prove to establish an affrmative defense. And for that rea-
son, that canon does not help to decide whether there is a
good-faith defense in § 841(a) prosecutions of physicians.
The Court does not claim that the “[e]xcept as authorized”
proviso actually constitutes an element of dispensing or dis-
tributing a controlled substance. But it concludes, based on
a vague four-part test, that the proviso is “suffciently like
an element in respect to the matter at issue here as to war-
rant similar legal treatment.” Ante, at 464. How many
other affrmative defenses might warrant similar treatment,
the Court does not say. It leaves prosecutors, defense attor-
neys, and the lower courts in the dark. I cannot accept this
cavalier treatment of an important question.

470 XIUL
U RUAN v. UNITED STATES
Alito, J., concurring in judgment
Nor can I accept the Court's conclusion that once a defend-
ant
produces evidence that his or her conduct was “author-
ized,” “the Government must prove beyond a reasonable
doubt that the defendant knowingly or intentionally acted in
an unauthorized manner.” Ante, at 457. We did not grant
certiorari on the question of the burden of proof applicable
to authorizations to dispense or distribute controlled sub-
stances. No party has briefed this issue, and its resolution
is not essential to our decision in these cases. In keeping
with our normal practice, I would not address this question.
But because the Court volunteers its own answer, I will offer
one as well. As I see it, the text of the CSA does not show
that Congress intended to deviate from the common-law rule
that the burden of proving “affrmative defenses—indeed,
`all . . . circumstances of justifcation, excuse or alleviation'—
rest[s] on the defendant.” Patterson v. New York, 432 U. S.
197, 202 (1977) (quoting 4 W. Blackstone Commentaries
*201). And absolutely nothing in the text of the statute in-
dicates that Congress intended to impose a burden on the
Gover nment to disprove a ll asser ti ons of authorizati on
beyond a reasonable doubt.
I
A
As relevant here, § 841(a)(1) provides that “[e]xcept as au-
thorized by this subchapter, it shall be unlawful for any per-
son knowingly or intentionally . . . to manufacture, distrib-
ute, or dispense, or possess with intent to manufacture,
distribute, or dispense, . . . a controlled substance.” Accord-
ing to the Court's reasoning, the terms “knowingly or inten-
tionally” in § 841(a)(1) apply to the “except as authorized”
proviso at the beginning of the provision. But it is hard to
see how this could be true.
As a matter of elementary syntax, the adverbs “know-
ingly” and “intentionally” are most naturally understood to
modify the verbs that follow, i. e., “manufacture,” “distrib-
ute,” etc., and not the introductory phrase “except as author-
Page Proof Pending Publication

Page Proof Pending Publication
Cite
as: 597 U. S. 450 (2022)
471
Alito, J., concurring in judgment
ized.” That phrase, in turn, clearly modifes the term
“unlawfu
l.”
The Court does not suggest otherwise. It does not claim
that “knowingly or “intentionally” modifes the introductory
proviso in a grammatical sense. (If it did, the introductory
phrase would clearly be an element, and for reasons that I
will explain, infra, at 472–473, 21 U. S. C. § 885 unmistakably
rules that out.) Instead, the Court pointedly uses different
terminology. It repeatedly says that the phrase “knowingly
or intentionally” “applies” to the introductory phrase, ante,
at 454, 457, 458, 461, 468 (emphasis added). And it reaches
this conclusion based on grounds that have nothing to do
with grammar or syntax.
Specifcally, the Court relies on a substantive canon of in-
terpretation—the mens rea canon. Under this canon, the
Court interprets criminal statutes to require a mens rea for
each element of an offense “even where `the most grammati-
cal reading of the statute' does not support” that interpreta-
tion. Rehaif, 588 U. S., at ––– (quoting United States v. X-
Citement Video, Inc., 513 U. S. 64, 70 (1994)).* But until
*Why we have held that the mens rea canon allows courts to ignore
obvious textual evidence of congressional intent is not obvious. In our
constitutional system, it is Congress that has the power to defne the ele-
ments of criminal offenses, not the federal courts. Liparota v. United
States, 471 U. S. 419, 424 (1985); see also United States v. Davis, 588 U. S.
–––, ––– (2019) (“Only the people's elected representatives in the legisla-
ture are authorized to `make an act a crime' ” (quoting United States v.
Hudson, 7 Cranch 32, 34 (1812))). The mens rea canon is legitimate when
it is used to determine what elements Congress intended to include in the
defnition of an offense. See, e. g., Staples v. United States, 511 U. S. 600,
605 (1994) (explaining that the canon is founded on an inference of congres-
sional intent). But applying that canon to override the intentions of Con-
gress would be inconsistent with the Constitution's separation of powers.
Federal courts have no constitutional authority to re-write the statutes
Congress has passed based on judicial views about what constitutes
“sound” or “just” criminal law. Cf. X-Citement Video, 513 U. S., at 80–
82 (Scalia, J., dissenting) (criticizing our mens rea canon precedents for
“convert[ing a] rule of interpretation into a rule of law” binding on
Congress).

472 XIUL
U RUAN v. UNITED STATES
Alito, J., concurring in judgment
today, this canon has been applied only to elements, and the
“except
as authorized” introductory phrase in § 841(a)(1) is
plainly not an element.
“The defnition of the elements of a criminal offense is en-
trusted to the legislature, particularly in the case of federal
crimes, which are solely creatures of statute.” Liparota v.
United States, 471 U. S. 419, 424 (1985). See also Dixon v.
United States, 548 U. S. 1, 7 (2006). But authorization to
dispense or distribute a controlled substance lacks the most
basic features of an element of an offense. For one thing, it
is black-letter law that an indictment must allege “the ele-
ments of the offense charged.” Hamling v. United States,
418 U. S. 87, 117 (1974). So if lack of authorization were
an element, it would be necessary to allege that in every
§ 841(a)(1) indictment. But § 885 says that it is not “neces-
sary for the United States to negative any exemption or ex-
ception set forth in [the relevant subchapter] in any . . . in-
dictment.” Beyond that, the prosecution bears the burden
of producing evidence with respect to every element of a
crime. Patterson, 432 U. S., at 215. But § 885(a)(1) also
provides that “the burden of going forward with the evi-
dence with respect to any such exemption or exception shall
be upon the person claiming its beneft.” It could hardly
be more obvious that Congress did not cast the “except as
authorized” introductory proviso as an element of distribut-
ing or dispensing a controlled substance.
Instead, that proviso clearly creates an affrmative de-
fense—that is, a “justifcation or excuse which is a bar to the
imposition of criminal liability” on conduct that satisfes the
elements of an offense. 1 W. LaFave, Substantive Criminal
Law § 1.8(c) (3d ed. 2018). Section 841(a)(1) has two main
parts: a principal clause generally prohibiting “knowingly or
intentionally” doing certain things with respect to controlled
substances (i.e., manufacturing them, distributing them,
etc.), and a proviso indicating that these acts are unlawful
“except as authorized” by other statutory provisions. As
Page Proof Pending Publication

Cite
as: 597 U. S. 450 (2022)
473
Alito, J., concurring in judgment
we have long held, the default rule for interpreting provi-
si
ons with this structure is that “ `an exception made by a
proviso or other distinct clause' ” designates an affrmative
defense that the Government has no duty to “ `negative.' ”
Dixon, 548 U. S., at 13 (quoting McKelvey v. United States,
260 U. S. 353, 357 (1922)); see also United States v. Dickson,
15 Pet. 141, 165 (1841) (calling this “the general rule of law
which has always prevailed”). When this rule applies, it is
“ `incumbent on one who relies on such an exception to set it
up and establish it.' ” Dixon, 548 U. S., at 13 (quoting Mc-
Kelvey, 260 U. S., at 357).
The CSA explicitly incorporates this default rule. As
noted, § 885(a)(1) provides that the prosecution need not
“negative any exemption or exception set forth in this sub-
chapter in any complaint, information, indictment, or other
pleading or in any trial, hearing, or other proceeding.”
(Emphasis added.) Short of using the words “affrmative
defense,” there is no clearer way of indicating that authoriza-
tion constitutes an affrmative defense.
On the most natural reading, then, § 841(a)(1) creates an
offense that has as its elements (1) knowingly or intention-
ally (2) distributing or dispensing (3) a controlled substance.
The “[e]xcept as authorized” proviso recognizes an affr-
mative defense that excuses or justifes conduct that other-
wise would fall within § 841(a)(1)'s general prohibition. The
mens rea canon does not speak to the constituents of that
defense.
B
While the Court does not claim that the “[e]xcept as au-
thorized” proviso is an element of a § 841(a)(1) offense, the
Court argues that the proviso is “suffciently like an element
in respect to the matter at issue here” for the mens rea
canon to apply, ante, at 464. The Court provides four rea-
sons for this conclusion: “[T]he language of § 841 (which ex-
plicitly includes a `knowingly or intentionally' provision); the
crucial role authorization (or lack thereof ) plays in distin-
Page Proof Pending Publication

474 XIUL
U RUAN v. UNITED STATES
Alito, J., concurring in judgment
guishing morally blameworthy conduct from socially neces-
sary
conduct; the serious nature of the crime and its penal-
ties; and the vague, highly general language of the
regulation defning the bounds of prescribing authority.”
Ibid. Not one of these reasons withstands scrutiny.
“[T]he language of § 841.” The Court notes that this pro-
vision expressly sets out a mens rea that applies to the ele-
ments of the offense, ibid., but the vast majority of criminal
statutes share this characteristic. Therefore, this feature
does not set § 841 apart.
“[T]he crucial role authorization (or lack thereof) plays
in distinguishing morally blameworthy conduct from so-
cially necessary conduct.” The Court claims that authori-
zation separates out morally blameworthy innocent conduct;
but something very similar may be said about most, if not
all, affrmative defenses. Take the common-law defense of
duress. Duress “excuse[s] criminal conduct where the actor
was under an unlawful threat of imminent death or serious
bodily injury” and the “threat caused the actor to engage
in conduct violating the literal terms of the criminal law.”
United States v. Bailey, 444 U. S. 394, 409 (1980). But a per-
son who acts under duress is not “morally blameworthy”—
that is part of what it means to say that duress excuses
otherwise-criminal conduct. Similarly, individuals who kill
or wound another person in self-defense to prevent their own
death or serious injury are not considered morally blame-
worthy. No one supposes that these defenses are hybrids,
or that the mens rea canon is a guide to their content.
It is unclear why the Court thinks that § 841(a)'s affrma-
tive defense is different. There are hints in the Court's
opinion that it has crafted a special rule for doctors—for ex-
ample, the Court describes their conduct in writing prescrip-
tions as not just “innocent,” but “socially benefcial” and “so-
cially necessary.” Ante, at 459, 464. But § 841(a) is not a
doctor-specifc provision. Section 841(a)'s proviso presum-
ably applies in the same way for all § 841(a) defendants—
Page Proof Pending Publication

Cite
as: 597 U. S. 450 (2022)
475
Alito, J., concurring in judgment
whether they are drug dealers accused of selling heroin or
are
physicians charged with abusing their authority to pre-
scribe painkillers.
“[T]he serious nature of the crime and its penalties.”
The Court also suggests that authorization is “like an ele-
ment” because dispensing or distributing a controlled sub-
stance is a felony that carries a substantial sentence. But
would all felonies qualify? If not, where would the Court
draw the line? The Court provides no answers.
“[T]he vague, highly general language of the regulation
defning prescribing authority.” As the Court explains, the
regulation defning the authority of physicians to prescribe
controlled substances allows them to issue a prescription “for
a legitimate medical purpose . . . in the usual course of . . .
professional practice.” 21 CFR § 1306.04(a) (2021). But
§ 841(a) applies to many other types of violations and many
other categories of defendants. Is the proviso a hybrid ele-
ment/defense only for doctors? Would its status change if
the regulation were reframed in more specifc terms? How
can the status of a phrase in a statute depend upon an imple-
menting regulation? The Court provides no answer to
these or any other questions naturally raised by its ipse dixit
that the exception in § 841(a) is “suffciently like” an element
to require that it be treated as such in some respects but
not others.
C
The Court also errs in holding that, if a § 841(a)(1) defend-
ant “meets the burden of producing evidence that his or her
conduct was `authorized,' ” the Government has the burden
to “prove beyond a reasonable doubt that the defendant
knowingly or intentionally acted in an unauthorized man-
ner,” ante, at 457. As noted, the common-law rule was that
the defendant had the burden of production and persuasion
on any affrmative defense. And the Court has held that
when Congress does not address the burden of proof in the
text of a statute, “we presume that Congress intended to
Page Proof Pending Publication

476 XIUL
U RUAN v. UNITED STATES
Alito, J., concurring in judgment
preserve the common-law rule.” Smith v. United States,
568
U. S. 106, 112 (2013); see also Dixon, 548 U. S., at 13–14.
The Court identifes one and only one reason for deviating
from this background rule—the fact that § 885(a)(1) states
that “the burden of going forward with the evidence with
respect to any . . . exemption or exception shall be upon the
person claiming its beneft.” Because this provision does
not say expressly that a defendant also has the burden of
persuasion, the Court infers that Congress meant to allocate
that burden to the prosecution. That inference is unwar-
ranted. Section 885(a)(1) explicitly relieves the Government
of the burden of “negativ[ing]” exceptions “in any trial.”
And it is hard to see how the Government does not have
the burden to “negative” exceptions if it must affrmatively
disprove a prima facie case of authorization any time a de-
fendant satisfes the initial burden of production.
But even if one credits the majority's assumption that the
CSA partly deviates from the common-law rule by shifting
the burden of persuasion to the Government, the majority's
further holding that the Government must carry that burden
with proof “beyond a reasonable doubt” comes out of thin
air. The usual rule is that affrmative defenses must be
proved “by a preponderance of the evidence.” Id., at 17.
But the majority does not identify a single word in §§ 841(a)
(1), 885(a)(1), or any other provision of the CSA that even
suggests that the statute imposes a burden of disproving au-
thorization defenses beyond a reasonable doubt.
The only thing that could conceivably justify reading a
reasonable-doubt requirement into a statute that says noth-
ing on the subject is the principle that an ambiguous statute
must be interpreted, when possible, to avoid unconstitution-
ality. See A. Scalia & B. Garner, Reading Law: The Inter-
pretation of Legal Texts 247–251 (2012). But the Court does
not claim that it would be unconstitutional for Congress to
require the Government to prove lack of authorization by
only a preponderance of the evidence. Indeed, the Court
Page Proof Pending Publication

Page Proof Pending Publication
Cite
as: 597 U. S. 450 (2022)
477
Alito, J., concurring in judgment
does not even claim that it would be unconstitutional to shift
the
burden of persuasion to the defendant. Nor could it.
Our precedents establish that governments are “foreclosed
from shifting the burden of proof to the defendant only `when
an affrmative defense . . . negate[s] an element of the
crime.' ” Smith, 568 U. S., at 110 (quoting Martin v. Ohio,
480 U. S. 228, 237 (1987) (Powell, J., dissenting)). And we
have held that when an affrmative defense instead justifes
or “ `excuse[s] conduct that would otherwise be punishable,' ”
the “Government has no constitutional duty to overcome the
defense beyond a reasonable doubt.” 568 U. S., at 110 (quot-
ing Dixon, 548 U. S., at 6).
The authorization defense made available to prescribing
physicians by the CSA plainly does not negate any of the
defning elements of dispensing or distributing a controlled
substance in violation of § 841(a)(1). As a result, the Court
has no basis for reading a requirement to disprove authoriza-
tion into the CSA. And at a minimum, even if the Govern-
ment must bear the ultimate burden of persuasion once the
burden of production is satisfed, the CSA should be read to
preserve a traditional preponderance-of-the-evidence stand-
ard for authorization defenses.
II
My analysis thus far establishes that authorization is an
affrmative defense to liability under § 841(a)(1), and the con-
stituents of that defense cannot be identifed through brute-
force application of a canon designed to identify the elements
of an offense. In my view, the contours of that defense can
be elucidated only by examining the text, structure, and his-
tory of the provisions of the CSA that defne it. I turn to
that task now.
The authorization relied on by the petitioners in these
cases permits physicians registered with the federal Drug
Enforcement Administration to prescribe controlled sub-
stances to patients by prescription. §§ 822(b), 823(f ), 829(a).

478 XIUL
U RUAN v. UNITED STATES
Alito, J., concurring in judgment
As we have previously interpreted it, this authorization does
not
allow physicians to dispense controlled substances by
prescription for any reason they choose; instead, the authori-
zation “is limited to the dispensing and use of drugs `in
the course of professional practice or research.' ” United
States v. Moore, 423 U. S. 122, 141 (1975) (quoting § 802(20)
(1970 ed.)).
The notion of action taken “in the course of professional
practice” is not defned in the CSA, but our precedents hold
that when Congress employs a term of art “obviously trans-
planted from another legal source,” it “brings the old soil
with it.” George v. McDonough, 596 U. S. –––, ––– (2022)
(quoting Taggart v. Lorenzen, 587 U. S. –––, ––– (2019); in-
ternal quotation marks omitted). And the notion that a
prescription is authorized if it is issued in the course of pro-
fessional practice is directly traceable to the Harrison Act,
which prohibited “any person” from distributing or dispens-
ing coca leaves or opium “except in pursuance of a written
order” issued by a practitioner “in the course of his pro-
fessional practice only.” § 2, 38 Stat. 786. Arguably, the
phrase “in the course of . . . professional practice” could have
been read to refer only to conduct that conforms to the
standards of medical practice as a purely objective matter.
But our Harrison Act precedents interpreted that phrase to
refer to “bona fde medical practice,” which meant that any
prescription issued “in good faith” qualifed as an authorized
act of dispensing one of the drugs proscribed by the statute.
Linder, 268 U. S., at 17–18; see also Boyd v. United States,
271 U. S. 104, 107 (1926); Webb v. United States, 249 U. S. 96,
99 (1919).
Nothing in the CSA suggests that Congress intended to
depart from the preexisting understanding of action “in the
course of professional practice.” We have previously held
that the CSA incorporates settled understandings of “the ex-
emption given to doctors” to dispense controlled substances
“ `in the course of . . . professional practice' ” under the Har-
Page Proof Pending Publication

Cite
as: 597 U. S. 450 (2022)
479
Alito, J., concurring in judgment
rison Act. Moore, 423 U. S., at 139–140 (quoting 38 Stat.
786).
And the language of the CSA supports the same con-
clusions that we previously reached about the Harrison Act.
As our CSA precedents have explained, to act “in the course
of professional practice” is to engage in the practice of medi-
cine—or, as we have put it, to “act `as a physician.' ” Moore,
423 U. S., at 141. For a practitioner to “practice medicine,”
he or she must act for a medical purpose—which means aim-
ing to prevent, cure, or alleviate the symptoms of a disease
or injury—and must believe that the treatment is a medically
legitimate means of treating the relevant disease or injury.
But acting “as a physician” does not invariably mean act-
ing as a good physician, as an objective understanding of the
“in the course of professional practice” standard would sug-
gest. A doctor who makes negligent or even reckless mis-
takes in prescribing drugs is still “acting as a doctor”—he or
she is simply acting as a bad doctor. The same cannot be
said, however, when a doctor knowingly or purposefully is-
sues a prescription to facilitate “addiction and recreational
abuse,” Gonzales v. Oregon, 546 U. S. 243, 274 (2006). Ob-
jectives of that kind are alien to medical practice, and a doc-
tor who prescribes drugs for those purposes is not “acting
as a physician” in any meaningful sense.
I would thus hold that a doctor who acts in subjective good
faith in prescribing drugs is entitled to invoke the CSA's au-
thorization defense. Under the correct understanding of
that defense, a doctor acts “in the course of professional
practice” in issuing a prescription under the CSA if—but
only if—he or she believes in good faith that the prescription
is a valid means of pursuing a medical purpose. A doctor
who knows that he or she is acting for a purpose foreign to
medicine—such as facilitating addiction or recreational drug
abuse—is not protected by the CSA's authorization to dis-
tribute controlled substances by prescription. Such doctors
may be convicted of unlawfully distributing or dispensing a
controlled substance under § 841(a)(1).
Page Proof Pending Publication

480 XIUL
U RUAN v. UNITED STATES
Alito, J., concurring in judgment
Based on this holding, I would vacate the judgments of the
Cour
ts of Appeals below. And like the Court, I would leave
it to those courts to determine on remand whether the in-
structions provided in petitioners' respective trials ade-
quately described the good-faith defense and whether any
errors in the instructions were harmless.
Page Proof Pending Publication

Page Proof Pending Publication
Reporter’s Note
The attached opinion has been revised to refect the usual publication
and citation style of the United States Reports. The revised pagination
makes available the offcial United States Reports citation in advance of
publication. The syllabus has been prepared by the Reporter of Decisions
for the convenience of the reader and constitutes no part of the opinion of
the Court. A list of counsel who argued or fled briefs in this case, and
who were members of the bar of this Court at the time this case was
argued, has been inserted following the syllabus. Other revisions may
include adjustments to formatting, captions, citation form, and any errant
punctuation. The following additional edits were made:
p. 455, line 2 from bottom: “20–410” is replaced with “20–1410”
p. 456, line 13 from bottom: “App.” is replaced with “App. in No. 21–5261,
p.”
p. 469, line 5 from bottom: “legal” is inserted after “similar”