SLACK v. McDANIEL, WARDEN, et al.

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Syllabus
SLACK v. McDANIEL, WARDEN, et al.
certiorari to the united states court of appeals for
the ninth circuit
No. 98–6322. Argued October 4, 1999—Reargued March 29, 2000—
Decided April 26, 2000
After petitioner Slack was convicted of second-degree murder in Nevada
and his direct appeal was unsuccessful, he filed, in 1991, a federal habeas
corpus petition under 28 U. S. C. § 2254. Because he wished to litigate
claims he had not yet presented to the Nevada courts, but could not do
so under the rule requiring complete exhaustion of state remedies, see
Rose v. Lundy, 455 U. S. 509, Slack filed a motion to hold his federal
petition in abeyance while he returned to state court. The Federal Dis-
trict Court ordered the habeas petition dismissed without prejudice,
granting Slack leave to file an application to renew upon exhausting
state remedies. After unsuccessful state postconviction proceedings,
Slack filed anew in the federal court in 1995, presenting 14 claims for
relief. The State moved to dismiss, arguing that (1) Slack’s was a
mixed petition raising some claims which had been presented to the
state courts and some which had not, and (2) under the established
Ninth Circuit rule, claims not raised in Slack’s 1991 federal petition had
to be dismissed as an abuse of the writ. The District Court granted the
State’s motion, holding, first, that Slack’s 1995 petition was “[a] second or
successive petition,” even though his 1991 petition had been dismissed
without prejudice for a failure to exhaust state remedies. The court
then invoked the abuse of the writ doctrine to dismiss with prejudice
the claims Slack had not raised in the 1991 petition. The dismissal
order was filed in 1998, after which Slack filed in the District Court a
pleading captioned “Notice of Appeal.” Consistent with Circuit prac-
tice, the court treated the notice as an application for a certificate of
probable cause (CPC) under the version of § 2253 that existed before
enactment of the Antiterrorism and Effective Death Penalty Act of 1996
(AEDPA). It denied a CPC, concluding the appeal would raise no sub-
stantial issue. The Ninth Circuit likewise denied a CPC, so that Slack
was not permitted to appeal the order dismissing his petition.
Held:
1. Where a habeas petitioner seeks to initiate an appeal of the dis-
missal of his petition after April 24, 1996 (AEDPA’s effective date), the
right to appeal is governed by the requirements now found at § 2253(c)—
which provides, inter alia, that such an appeal may not be taken unless

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474 SLACK v. McDANIEL
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a circuit Justice or judge issues a certificate of appealability (COA),
§ 2253(c)(1), and that the COA may issue only if the applicant has
made a substantial showing of the denial of a constitutional right,
§ 2253(c)(2)—even though the habeas petition was filed in the district
court before AEDPA’s effective date. Slack argues incorrectly that the
pre-AEDPA version of the statute, not § 2253(c), controls his case
because, in Lindh v. Murphy, 521 U. S. 320, 327, this Court held that
AEDPA’s § 2254 amendments governing entitlement to district court ha-
beas relief applied to cases filed after AEDPA’s effective date. In im-
plementing Lindh, it must be recognized that § 2254 is directed to dis-
trict court proceedings while § 2253 is directed to appellate proceedings.
Just as § 2254 applies to cases filed in the trial court post-AEDPA, § 2253
applies to appellate proceedings initiated post-AEDPA. Although
Lindh requires a court of appeals to apply pre-AEDPA law in reviewing
the trial court’s ruling in cases commenced there pre-AEDPA, post-
AEDPA law governs the right to appeal in cases such as the present.
While an appeal is a continuation of the litigation started in the trial
court, it is a distinct step. E. g., Hohn v. United States, 524 U. S. 236,
241. Under AEDPA, an appellate case is commenced when the appli-
cation for a COA is filed. Ibid. When Congress instructs that ap-
plication of a statute is triggered by the commencement of a case, the
relevant case for a statute directed to appeals is the one initiated in
the appellate court. Because Slack sought appellate review of the dis-
missal of his habeas petition two years after AEDPA’s effective date,
§ 2253(c) governs here, and Slack must apply for a COA. The Ninth
Circuit should have treated his notice of appeal as such an application.
Pp. 480–482.
2. When the district court denies a habeas petition on procedural
grounds without reaching the prisoner’s underlying constitutional claim,
a COA should issue (and an appeal of the district court’s order may
be taken) if the prisoner shows, at least, that jurists of reason would
find it debatable whether the petition states a valid claim of the denial
of a constitutional right, and that jurists of reason would find it debat-
able whether the district court was correct in its procedural ruling.
Pp. 483–485.
(a) The Court rejects the State’s contentions that, because § 2253(c)
provides that a COA may issue upon the “substantial showing of the
denial of a constitutional right,” only constitutional rulings may be
appealed, and no appeal can be taken if the district court relies on pro-
cedural grounds to dismiss the petition. In setting forth the precondi-
tions for issuance of a COA under § 2253(c), Congress expressed no
intention to allow trial court procedural error to bar vindication of sub-
stantial constitutional rights on appeal. This conclusion follows from

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AEDPA’s present provisions, which incorporate earlier habeas corpus
principles. Except for substituting the word “constitutional” for the
word “federal,” the present § 2253 is a codification of the CPC standard
announced in Barefoot v. Estelle, 463 U. S. 880, 894. See Williams v.
Taylor, ante, at 434. Under Barefoot, a substantial showing of the de-
nial of a right includes showing that reasonable jurists could debate
whether (or, for that matter, agree that) the petition should have been
resolved in a different manner or that the issues presented were “ ‘ade-
quate to deserve encouragement to proceed further.’ ” 463 U. S., at 893,
and n. 4. Pp. 483–484.
(b) Determining whether a COA should issue where the petition
was dismissed on procedural grounds has two components, one directed
at the underlying constitutional claims and one directed at the district
court’s procedural holding. Section 2253 mandates that both showings
be made before the court of appeals may entertain the appeal. Each
component is part of a threshold inquiry, and a court may find that it
can dispose of the application in a fair and prompt manner if it proceeds
first to resolve the issue whose answer is more apparent from the record
and arguments. Resolution of procedural issues first is allowed and
encouraged by the rule that this Court will not pass upon a constitu-
tional question if there is also present some other ground upon which
the case may be disposed of. Ashwander v. TVA, 297 U. S. 288, 347.
Here, Slack did not attempt to make a substantial showing of the denial
of a constitutional right, instead arguing only that the District Court’s
procedural rulings were wrong. This Court does not attempt to deter-
mine whether Slack could make the required showing of constitutional
error, for the issue was neither briefed nor presented below because of
the view that the CPC, rather than COA, standards applied. It will be
necessary to consider the matter upon any remand for further proceed-
ings. The Court does, however, address the second component of the
§ 2253(c) inquiry, whether jurists of reason could conclude that the Dis-
trict Court’s dismissal on procedural grounds was debatable or incor-
rect. Pp. 484–485.
3. A habeas petition which is filed after an initial petition was dis-
missed without adjudication on the merits for failure to exhaust state
remedies is not a “second or successive” petition as that term is under-
stood in the habeas corpus context. Pp. 485–490.
(a) The District Court erred in concluding to the contrary. Be-
cause the question whether Slack’s pre-AEDPA, 1995 petition was sec-
ond or successive implicates his right to relief in the trial court, pre-
AEDPA law governs. See Lindh v. Murphy, supra. Whether the
dismissal was appropriate is controlled by Rule 9(b) of the Rules Gov-
erning § 2254, which incorporates the Court’s prior decisions on the

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subject, McCleskey v. Zant, 499 U. S. 467, 487, and states: “A second
or successive petition [alleging new and different grounds] may be dis-
missed if . . . the judge finds that the failure . . . to assert those grounds
in a prior petition constituted an abuse of the writ.” The “second or
successive petition” phrase is a term of art given substance in, e. g.,
Rose v. Lundy, 455 U. S., at 510, which held that a district court must
dismiss habeas petitions containing both exhausted and unexhausted
claims, but contemplated that the prisoner could return to federal court
after the requisite exhaustion, id., at 520–521. Thus, a petition filed
after a mixed petition has been dismissed under Rose v. Lundy before
the district court adjudicated any claims is to be treated as any other
first petition and is not a second or successive petition. Neither Rose
v. Lundy nor Stewart v. Martinez-Villareal, 523 U. S. 637 (1998), sup-
ports the State’s contention that the prisoner, upon his return to federal
court, should be restricted to the claims made in his initial petition. It
is instead more appropriate to treat the initial mixed petition as though
it had not been filed, subject to whatever conditions the court attaches
to the dismissal. Accordingly, Slack’s 1995 petition should not have
been dismissed on the grounds that it was second or successive. To the
extent that the Court’s ruling might allow prisoners repeatedly to re-
turn to state court and thereby inject undue delay into the collateral
review process, the problem can be countered under the States’ power
to impose proper procedural bars and the federal courts’ broad powers
to prevent duplicative or unnecessary litigation. Pp. 485–489.
(b) Thus, Slack has demonstrated that reasonable jurists could con-
clude that the District Court’s abuse of the writ holding was wrong.
Whether Slack is otherwise entitled to the issuance of a COA is a ques-
tion to be resolved first upon remand. Pp. 489–490.
Reversed and remanded.
Kennedy, J., delivered the opinion of the Court, Part I of which was
unanimous, Part II of which was joined by Rehnquist, C. J., and O’Con-
nor, Scalia, Thomas, and Ginsburg, JJ., and Parts III and IV of which
were joined by Rehnquist, C. J., and Stevens, O’Connor, Souter,
Ginsburg, and Breyer, JJ. Stevens, J., filed an opinion concurring in
part and concurring in the judgment, in which Souter and Breyer, JJ.,
joined, post, p. 490. Scalia, J., filed an opinion concurring in part and
dissenting in part, in which Thomas, J., joined, post, p. 490.
Michael Pescetta, by appointment of the Court, 526 U. S.
1049, argued and reargued the cause for petitioner. With
him on the briefs was Timothy P. O’Toole.

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Opinion of the Court
Matthew D. Roberts argued the cause for the United
States as amicus curiae. With him on the brief were
Solicitor General Waxman, Assistant Attorney General
Robinson, Deputy Solicitor General Dreeben, and Vicki
S. Marani.
David F. Sarnowski, Chief Deputy Attorney General of
Nevada, argued and reargued the cause for respondents.
With him on the briefs were Frankie Sue Del Papa, Attor-
ney General, and Julie A. Slabaugh, Deputy Attorney Gen-
eral. With him on the brief on the original argument was
Ms. Del Papa.*
Justice Kennedy delivered the opinion of the Court.
We are called upon to resolve a series of issues regarding
the law of habeas corpus, including questions of the proper
application of the Antiterrorism and Effective Death Penalty
Act of 1996 (AEDPA). We hold as follows:
*Briefs of amici curiae urging reversal were filed for the National Asso-
ciation of Criminal Defense Lawyers et al. by Edward M. Chikofsky, Bar-
bara E. Bergman, and David M. Porter; and for the Rutherford Institute
by John W. Whitehead.
Briefs of amici curiae urging affirmance were filed for the State of
California et al. by Bill Lockyer, Attorney General of California, David P.
Druliner, Chief Assistant Attorney General, Carol Wendelin Pollack, Se-
nior Assistant Attorney General, and Donald E. De Nicola and A. Scott
Hayward, Deputy Attorneys General, joined by the Attorneys General for
their respective States as follows: Bill Pryor of Alabama, Bruce M. Bo-
telho of Alaska, Janet Napolitano of Arizona, Mark Pryor of Arkansas,
M. Jane Brady of Delaware, Robert A. Butterworth of Florida, Thomas J.
Miller of Iowa, Alan G. Lance of Idaho, Carla J. Stovall of Kansas, Rich-
ard P. Ieyoub of Louisiana, Mike Moore of Mississippi, Jeremiah W. (Jay)
Nixon of Missouri, Joseph P. Mazurek of Montana, Don Stenberg of
Nebraska, Patricia A. Madrid of New Mexico, Michael F. Easley of
North Carolina, W. A. Drew Edmondson of Oklahoma, D. Michael Fisher
of Pennsylvania, Charles M. Condon of South Carolina, Mark Barnett
of South Dakota, Paul G. Summers of Tennessee, Mark L. Earley of
Virginia, and Christine O. Gregoire of Washington; and for the Criminal
Justice Legal Foundation by Kent S. Scheidegger.

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First, when a habeas corpus petitioner seeks to initiate
an appeal of the dismissal of a habeas corpus petition after
April 24, 1996 (the effective date of AEDPA), the right to
appeal is governed by the certificate of appealability (COA)
requirements now found at 28 U. S. C. § 2253(c) (1994 ed.,
Supp. III). This is true whether the habeas corpus petition
was filed in the district court before or after AEDPA’s effec-
tive date.
Second, when the district court denies a habeas petition
on procedural grounds without reaching the prisoner’s un-
derlying constitutional claim, a COA should issue (and an
appeal of the district court’s order may be taken) if the pris-
oner shows, at least, that jurists of reason would find it de-
batable whether the petition states a valid claim of the denial
of a constitutional right, and that jurists of reason would
find it debatable whether the district court was correct in its
procedural ruling.
Third, a habeas petition which is filed after an initial peti-
tion was dismissed without adjudication on the merits for
failure to exhaust state remedies is not a “second or succes-
sive” petition as that term is understood in the habeas corpus
context. Federal courts do, however, retain broad powers
to prevent duplicative or unnecessary litigation.
I
Petitioner Antonio Slack was convicted of second-degree
murder in Nevada state court in 1990. His direct appeal
was unsuccessful. On November 27, 1991, Slack filed a peti-
tion for writ of habeas corpus in federal court under 28
U. S. C. § 2254. Early in the federal proceeding, Slack de-
cided to litigate claims he had not yet presented to the Ne-
vada courts. He could not raise the claims in federal court
because, under the exhaustion of remedies rule explained in
Rose v. Lundy, 455 U. S. 509 (1982), a federal court was re-
quired to dismiss a petition presenting claims not yet liti-

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gated in state court. Accordingly, Slack filed a motion seek-
ing to hold his federal petition in abeyance while he returned
to state court to exhaust the new claims. Without objection
by the State, the District Court ordered the habeas petition
dismissed “without prejudice.” The order, dated February
19, 1992, further stated, “Petitioner is granted leave to file an
application to renew upon exhaustion of all State remedies.”
Slack v. Director, Nev. Dept. of Prisons, No. CV–N–91–561
(D. Nev.), App. 22.
After an unsuccessful round of state postconviction pro-
ceedings, Slack filed a new federal habeas petition on May
30, 1995. The District Court later appointed counsel, direct-
ing him to file an amended petition or a notice of intention
to proceed with the current petition. On December 24, 1997,
counsel filed an amended petition presenting 14 claims for
relief. The State moved to dismiss the petition. As its first
ground, the State argued that Slack’s petition must be dis-
missed because it was a mixed petition, that is to say a peti-
tion raising some claims which had been presented to the
state courts and some which had not. As its second ground,
the State cited Farmer v. McDaniel, 98 F. 3d 1548 (CA9
1996), and contended that, under the established rule in the
Ninth Circuit, claims Slack had not raised in his 1991 federal
habeas petition must be dismissed as an abuse of the writ.
The District Court granted the State’s motion. First, the
court relied on Farmer to hold that Slack’s 1995 petition was
“[a] second or successive petition,” even though his 1991 peti-
tion had been dismissed without prejudice for a failure to
exhaust state remedies. The court then invoked the abuse
of the writ doctrine to dismiss with prejudice the claims
Slack had not raised in the 1991 petition. This left Slack
with four claims, each having been raised in the 1991 peti-
tion; but one of these, the court concluded, had not yet been
presented to the state courts. The court therefore dis-
missed Slack’s remaining claims because they were in a

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mixed petition. Here, Slack seeks to challenge the dismissal
of claims as abusive; he does not contend that all claims pre-
sented in the amended petition were exhausted.
The District Court’s dismissal order was filed March 30,
1998. On April 29, 1998, Slack filed in the District Court
a pleading captioned “Notice of Appeal.” Consistent with
Circuit practice, the court treated the notice as an applica-
tion for a certificate of probable cause (CPC) under the pre-
AEDPA version of 28 U. S. C. § 2253; and it denied a CPC,
concluding the appeal would raise no substantial issue. The
Court of Appeals likewise denied a CPC. No. CV–95–194
(CA9, July 7, 1998), App. 197. As a result, Slack was not
permitted to take an appeal of the order dismissing his peti-
tion. We granted certiorari. 525 U. S. 1138 (1999). Slack
contends that he is entitled to an appeal of the dismissal of
his petition, arguing that the District Court was wrong to
hold that his 1995 petition was “second or successive.” We
agree that Slack’s 1995 petition was not second or successive,
but first we must resolve two preliminary questions.
II
Before AEDPA, appellate review of the dismissal of a ha-
beas petition was governed by a version of 28 U. S. C. § 2253
enacted in 1948. Act of June 25, 1948, 62 Stat. 967. The
statute provided no appeal could be taken from the final
order in a habeas corpus proceeding “unless the justice or
judge who rendered the order or a circuit justice or judge
issues a certificate of probable cause.” Ibid. The statute
did not explain the standards for the issuance of a CPC, but
the Court established what a prisoner must show to obtain
a CPC in Barefoot v. Estelle, 463 U. S. 880 (1983): “a substan-
tial showing of the denial of a federal right.” Id., at 893
(citation and brackets omitted).
Effective April 24, 1996, AEDPA amended § 2253. As rel-
evant here, AEDPA added subsection (c), which provides:

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“(1) Unless a circuit justice or judge issues a certifi-
cate of appealability, an appeal may not be taken to the
court of appeals from—
“(A) the final order in a habeas corpus proceeding in
which the detention complained of arises out of process
issued by a State court; or
“(B) the final order in a proceeding under section
2255.
“(2) A certificate of appealability may issue under
paragraph (1) only if the applicant has made a substan-
tial showing of the denial of a constitutional right.
“(3) The certificate of appealability under paragraph
(1) shall indicate which specific issue or issues satisfy
the showing required by paragraph (2).” 28 U. S. C.
§ 2253(c) (1994 ed., Supp. III).
The issue we consider at the outset is whether the pre- or
post-AEDPA version of § 2253 controls Slack’s right to ap-
peal. In Lindh v. Murphy, 521 U. S. 320 (1997), the Court
held that AEDPA’s amendments to 28 U. S. C. § 2254, the
statute governing entitlement to habeas relief in the district
court, applied to cases filed after AEDPA’s effective date.
521 U. S., at 327. Slack contends that Lindh means § 2253(c)
does not apply to him because his case was commenced in
the District Court pre-AEDPA. That position is incorrect.
For purposes of implementing the holding in Lindh, it must
be recognized that § 2254 is directed to proceedings in the
district courts while § 2253 is directed to proceedings in
the appellate courts. Just as § 2254 applies to cases filed
in the trial court post-AEDPA, § 2253 applies to appellate
proceedings initiated post-AEDPA. True, Lindh requires a
court of appeals to apply pre-AEDPA law in reviewing the
trial court’s ruling, for cases commenced there pre-AEDPA;
but post-AEDPA law governs the right to appeal in cases
such as the one now before us.
While an appeal is a continuation of the litigation started
in the trial court, it is a distinct step. Hohn v. United

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States, 524 U. S. 236, 241 (1998); Mackenzie v. A. Engel-
hard & Sons Co., 266 U. S. 131 (1924). We have described
proceedings in the courts of appeals as “appellate cases.”
E. g., Order of Apr. 30, 1991, 500 U. S. 1009 (amendments to
Federal Rules of Appellate Procedure “shall govern all pro-
ceedings in appellate cases thereafter commenced”). Under
AEDPA, an appellate case is commenced when the applica-
tion for a COA is filed. Hohn, supra, at 241. When Con-
gress instructs us (as Lindh says it has) that application of
a statute is triggered by the commencement of a case, the
relevant case for a statute directed to appeals is the one initi-
ated in the appellate court. Thus, § 2253(c) governs appel-
late court proceedings filed after AEDPA’s effective date.
We see no indication that Congress intended to tie appli-
cation of the provisions to the date a petition was filed in
the district court. The COA statute establishes procedural
rules and requires a threshold inquiry into whether the cir-
cuit court may entertain an appeal. Hohn, supra, at 248;
cf. Lindh, supra, at 327. Because Slack sought appellate
review two years after AEDPA’s effective date, § 2253(c)
governs his right to appeal.
We further note that we applied § 2253 in our post-Lindh
decision in Hohn, a case which arrived in the same posture
as this case. Like Slack, Hohn argued § 2253(c) did not apply
because his petition had been filed in the District Court be-
fore AEDPA’s effective date. Brief for Petitioner in Hohn
v. United States, O. T. 1997, No. 96–8986, pp. 40–44. Though
our opinion did not discuss whether § 2253(c) applied to Hohn,
we would have had no reason to reach the issue we did re-
solve, that we had statutory certiorari jurisdiction to review
the denial of a COA, if AEDPA did not apply at all. Our
disposition today is consistent with Hohn. AEDPA governs
the conditions of Slack’s appeal, and so he was required to
seek a COA to obtain appellate review of the dismissal of his
habeas petition.

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III
As AEDPA applied, the Court of Appeals should have
treated the notice of appeal as an application for a COA.
Fed. Rule App. Proc. 22(b); Fed. Rule Civ. Proc. 8(f); see
also Hohn, supra, at 240. To evaluate whether the Court of
Appeals should have granted a COA, we must determine
what the habeas applicant must show to satisfy the require-
ments of § 2253(c).
Citing § 2253(c)’s requirement that a COA may issue only
upon the “substantial showing of the denial of a constitu-
tional right,” the State contends that no appeal can be taken
if the District Court relies on procedural grounds to dismiss
the petition. According to the State, only constitutional rul-
ings may be appealed. Under this view, a state prisoner
who can demonstrate he was convicted in violation of the
Constitution and who can demonstrate that the district court
was wrong to dismiss the petition on procedural grounds
would be denied relief. We reject this interpretation. The
writ of habeas corpus plays a vital role in protecting consti-
tutional rights. In setting forth the preconditions for issu-
ance of a COA under § 2253(c), Congress expressed no inten-
tion to allow trial court procedural error to bar vindication
of substantial constitutional rights on appeal.
Our conclusion follows from AEDPA’s present provisions,
which incorporate earlier habeas corpus principles. Under
AEDPA, a COA may not issue unless “the applicant has
made a substantial showing of the denial of a constitutional
right.” 28 U. S. C. § 2253(c) (1994 ed., Supp. III). Except
for substituting the word “constitutional” for the word “fed-
eral,” § 2253 is a codification of the CPC standard announced
in Barefoot v. Estelle, 463 U. S., at 894. Congress had before
it the meaning Barefoot had given to the words it selected;
and we give the language found in § 2253(c) the meaning
ascribed it in Barefoot, with due note for the substitution
of the word “constitutional.” See Williams v. Taylor, ante,
at 434. To obtain a COA under § 2253(c), a habeas prisoner

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must make a substantial showing of the denial of a constitu-
tional right, a demonstration that, under Barefoot, includes
showing that reasonable jurists could debate whether (or, for
that matter, agree that) the petition should have been re-
solved in a different manner or that the issues presented
were “ ‘adequate to deserve encouragement to proceed fur-
ther.’ ” Barefoot, supra, at 893, and n. 4 (“sum[ming] up”
the “ ‘substantial showing’ ” standard).
Where a district court has rejected the constitutional
claims on the merits, the showing required to satisfy § 2253(c)
is straightforward: The petitioner must demonstrate that
reasonable jurists would find the district court’s assessment
of the constitutional claims debatable or wrong. The issue
becomes somewhat more complicated where, as here, the
district court dismisses the petition based on procedural
grounds. We hold as follows: When the district court denies
a habeas petition on procedural grounds without reaching
the prisoner’s underlying constitutional claim, a COA should
issue when the prisoner shows, at least, that jurists of reason
would find it debatable whether the petition states a valid
claim of the denial of a constitutional right and that jurists
of reason would find it debatable whether the district court
was correct in its procedural ruling. This construction
gives meaning to Congress’ requirement that a prisoner
demonstrate substantial underlying constitutional claims and
is in conformity with the meaning of the “substantial show-
ing” standard provided in Barefoot, supra, at 893, and n. 4,
and adopted by Congress in AEDPA. Where a plain pro-
cedural bar is present and the district court is correct to in-
voke it to dispose of the case, a reasonable jurist could not
conclude either that the district court erred in dismissing
the petition or that the petitioner should be allowed to pro-
ceed further. In such a circumstance, no appeal would be
warranted.
Determining whether a COA should issue where the peti-
tion was dismissed on procedural grounds has two compo-

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nents, one directed at the underlying constitutional claims
and one directed at the district court’s procedural holding.
Section 2253 mandates that both showings be made before
the court of appeals may entertain the appeal. Each compo-
nent of the § 2253(c) showing is part of a threshold inquiry,
and a court may find that it can dispose of the application in
a fair and prompt manner if it proceeds first to resolve the
issue whose answer is more apparent from the record and
arguments. The recognition that the “Court will not pass
upon a constitutional question although properly presented
by the record, if there is also present some other ground
upon which the case may be disposed of,” Ashwander v. TVA,
297 U. S. 288, 347 (1936) (Brandeis, J., concurring), allows and
encourages the court to first resolve procedural issues. The
Ashwander rule should inform the court’s discretion in this
regard.
In this case, Slack did not attempt to make a substantial
showing of the denial of a constitutional right, instead ar-
guing only that the District Court’s procedural rulings were
wrong. We will not attempt to determine whether Slack
could make the required showing of constitutional error, for
the issue was neither briefed nor presented below because
of the view that the CPC, rather than COA, standards ap-
plied. It will be necessary to consider the matter upon any
remand for further proceedings. We will, however, address
the second component of the § 2253(c) inquiry, whether ju-
rists of reason could conclude that the District Court’s dis-
missal on procedural grounds was debatable or incorrect.
The issue has been discussed in the briefs presented to us; it
is the question upon which we granted certiorari; and its
resolution would end the case, were we to decide the matter
in the State’s favor.
The District Court dismissed claims Slack failed to raise
in his 1991 petition based on its conclusion that Slack’s 1995
petition was a second or successive habeas petition. This
conclusion was wrong. A habeas petition filed in the district

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486 SLACK v. McDANIEL
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court after an initial habeas petition was unadjudicated on
its merits and dismissed for failure to exhaust state remedies
is not a second or successive petition.
Slack commenced this habeas proceeding in the District
Court in 1995, before AEDPA’s effective date. Because the
question whether Slack’s petition was second or successive
implicates his right to relief in the trial court, pre-AEDPA
law governs, see Lindh v. Murphy, 521 U. S. 320 (1997),
though we do not suggest the definition of second or succes-
sive would be different under AEDPA. See Stewart v.
Martinez-Villareal, 523 U. S. 637 (1998) (using pre-AEDPA
law to interpret AEDPA’s provision governing “second or
successive habeas applications”). The parties point us to
Rule 9(b) of the Rules Governing Section 2254 Cases in the
United States District Courts as controlling the issue. The
Rule incorporates our prior decisions regarding successive
petitions and abuse of the writ, McCleskey v. Zant, 499 U. S.
467, 487 (1991), and states: “A second or successive petition
[alleging new and different grounds] may be dismissed if . . .
the judge finds that the failure of the petitioner to assert
those grounds in a prior petition constituted an abuse of the
writ.” As the text demonstrates, Rule 9(b) applies only to
“a second or successive petition.”
The phrase “second or successive petition” is a term of
art given substance in our prior habeas corpus cases. The
Court’s decision in Rose v. Lundy, 455 U. S., at 510, instructs
us in reaching our understanding of the term. Rose v.
Lundy held that a federal district court must dismiss habeas
corpus petitions containing both exhausted and unexhausted
claims. The opinion, however, contemplated that the pris-
oner could return to federal court after the requisite exhaus-
tion. Id., at 520 (“Those prisoners who . . . submit mixed
petitions nevertheless are entitled to resubmit a petition
with only exhausted claims or to exhaust the remainder of
their claims”). It was only if a prisoner declined to return
to state court and decided to proceed with his exhausted

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487 Cite as: 529 U. S. 473 (2000)
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claims in federal court that the possibility arose that a subse-
quent petition would be considered second or successive and
subject to dismissal as an abuse of the writ. Id., at 520–521
(plurality opinion) (“[A] prisoner who decides to proceed only
with his exhausted claims and deliberately sets aside his
unexhausted claims risks dismissal of subsequent federal
petitions”).
This understanding of the second or successive rule was
confirmed two Terms ago when we wrote as follows: “[N]one
of our cases . . . have ever suggested that a prisoner whose
habeas petition was dismissed for failure to exhaust state
remedies, and who then did exhaust those remedies and
returned to federal court, was by such action filing a succes-
sive petition. A court where such a petition was filed could
adjudicate these claims under the same standard as would
govern those made in any other first petition.” Stewart v.
Martinez-Villareal, supra, at 644. We adhere to this analy-
sis. A petition filed after a mixed petition has been dis-
missed under Rose v. Lundy before the district court adjudi-
cated any claims is to be treated as “any other first petition”
and is not a second or successive petition.
The State contends that the prisoner, upon his return
to federal court, should be restricted to the claims made in
his initial petition. Neither Rose v. Lundy nor Martinez-
Villareal requires this result, which would limit a prisoner
to claims made in a pleading that is often uncounseled, hand-
written, and pending in federal court only until the State
identifies one unexhausted claim. The proposed rule would
bar the prisoner from raising nonfrivolous claims developed
in the subsequent state exhaustion proceedings contem-
plated by the Rose dismissal, even though a federal court
had yet to review a single constitutional claim. This result
would be contrary to our admonition that the complete ex-
haustion rule is not to “trap the unwary pro se prisoner.”
Rose supra, at 520 (internal quotation marks omitted). It
is instead more appropriate to treat the initial mixed petition

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488 SLACK v. McDANIEL
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as though it had not been filed, subject to whatever condi-
tions the court attaches to the dismissal. Rose v. Lundy
dictated that, whatever particular claims the petition con-
tained, none could be considered by the federal court.
Slack’s 1991 petition was dismissed under the procedure
established in Rose v. Lundy. No claim made in Slack’s 1991
petition was adjudicated during the three months it was
pending in federal court. As such, the 1995 petition should
not have been dismissed on the grounds that it was second
or successive. Reasoning to the contrary found in the Court
of Appeals’ Farmer decision, rendered before Martinez-
Villareal, is incorrect. See also In re Turner, 101 F. 3d 1323
(CA9 1997) (refusing to apply rules governing second or suc-
cessive petitions to a petitioner whose prior habeas petition
had been dismissed for failure to exhaust). Our view that
established practice demonstrates that Slack’s 1995 petition
is not second or successive is confirmed as well by opinions
of the Courts of Appeals which have addressed the point
under similar circumstances. E. g., Carlson v. Pitcher, 137
F. 3d 416, 420 (CA6 1998) (“We join with every other court
to consider the question, and hold that a habeas petition filed
after a previous petition has been dismissed on exhaustion
grounds is not a ‘second or successive’ petition”); Turner,
supra; Christy v. Horn, 115 F. 3d 201, 208 (CA3 1997); Dick-
inson v. Maine, 101 F. 3d 791 (CA1 1996); Camarano v. Irvin,
98 F. 3d 44, 45–46 (CA2 1996).
The State complains that this rule is unfair. The filing of
a mixed petition in federal court requires it to appear and
to plead failure to exhaust. The petition is then dismissed
without prejudice, allowing the prisoner to make a return
trip through the state courts to exhaust new claims. The
State expresses concern that, upon exhaustion, the prisoner
would return to federal court but again file a mixed petition,
causing the process to repeat itself. In this manner, the
State contends, a vexatious litigant could inject undue delay
into the collateral review process. To the extent the tactic

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would become a problem, however, it can be countered with-
out upsetting the established meaning of a second or succes-
sive petition.
First, the State remains free to impose proper procedural
bars to restrict repeated returns to state court for postcon-
viction proceedings. Second, provisions of AEDPA may
bear upon the question in cases to which the Act applies.
AEDPA itself demonstrates that Congress may address mat-
ters relating to exhaustion and mixed petitions through
means other than rules governing “second or successive” pe-
titions. E. g., 28 U. S. C. § 2254(b)(2) (1994 ed., Supp. III).
Third, the Federal Rules of Civil Procedure, applicable as a
general matter to habeas cases, vest the federal courts with
due flexibility to prevent vexatious litigation. As Slack con-
cedes, in the habeas corpus context it would be appropriate
for an order dismissing a mixed petition to instruct an appli-
cant that upon his return to federal court he is to bring only
exhausted claims. See Fed. Rules Civ. Proc. 41(a) and (b).
Once the petitioner is made aware of the exhaustion require-
ment, no reason exists for him not to exhaust all potential
claims before returning to federal court. The failure to com-
ply with an order of the court is grounds for dismissal with
prejudice. Fed. Rule Civ. Proc. 41(b). In this case, how-
ever, the initial petition was dismissed without condition and
without prejudice. We reject the State’s argument that re-
fusing to give a new meaning to the established term “second
or successive” opens the door to the abuses described.
IV
Slack has demonstrated that reasonable jurists could con-
clude that the District Court’s abuse of the writ holding was
wrong, for we have determined that a habeas petition filed
after an initial petition was dismissed under Rose v. Lundy
without an adjudication on the merits is not a “second or
successive” petition. Whether Slack is otherwise entitled to
the issuance of a COA is a question to be resolved first upon

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490 SLACK v. McDANIEL
Opinion of Scalia, J.
remand. The judgment of the Court of Appeals is reversed,
and the case is remanded for further proceedings consistent
with this opinion.
It is so ordered.
Justice Stevens, with whom Justice Souter and
Justice Breyer join, concurring in part and concurring
in the judgment.
With respect to the issue resolved in Part II of the Court’s
opinion, I agree with the Courts of Appeals that have held
that the pre-AEDPA version of 28 U. S. C. § 2253 governs
the right to appeal with respect to an appeal noticed after
the effective date of AEDPA in a habeas corpus proceeding
commenced prior to that date. See Fuller v. Roe, 182 F. 3d
699, 702 (CA9 1999) (per curiam); Crowell v. Walsh, 151
F. 3d 1050, 1051–1052 (CADC 1998); Tejeda v. Dubois, 142
F. 3d 18, 22, n. 4 (CA1 1998); Berrios v. United States, 126
F. 3d 430, 431, n. 2 (CA2 1997); United States v. Kunzman,
125 F. 3d 1363, 1364, n. 2 (CA10 1997); United States v. Skan-
dier, 125 F. 3d 178, 179–182 (CA3 1997); Hardwick v. Single-
tary, 122 F. 3d 935, 936 (per curiam), vacated in part on
other grounds, 126 F. 3d 1312 (CA11 1997) (per curiam);
Arredondo v. United States, 120 F. 3d 639, 640 (CA6 1997);
United States v. Carter, 117 F. 3d 262, 264 (CA5 1997) (per
curiam); but see Tiedeman v. Benson, 122 F. 3d 518, 520–521
(CA8 1997).
I do, however, join the balance of the Court’s opinion and
its judgment.
Justice Scalia, with whom Justice Thomas joins,
concurring in part and dissenting in part.
I join the opinion of the Court, except for its discussion
in Parts III and IV of whether Slack’s postexhaustion peti-
tion was second or successive. I believe that the Court pro-
duces here, as it produced in a different respect in Stewart
v. Martinez-Villareal, 523 U. S. 637 (1998), see id., at 646

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(Scalia, J., dissenting), a distortion of the natural meaning
of the term “second or successive.”
The opinion relies on Martinez-Villareal, together with
Rose v. Lundy, 455 U. S. 509 (1982), to conclude that a pris-
oner whose federal petition is dismissed to allow exhaustion
may return to federal court without having his later petition
treated as second or successive, regardless of what claims it
contains. Neither the holdings nor even the language of
those opinions suggest that proposition. As for holdings:
Martinez-Villareal did not even involve the issue of exhaus-
tion, and so has no bearing upon the present case. The nar-
row holding of Rose v. Lundy was that a habeas petition
containing both exhausted and unexhausted claims must be
dismissed, but it can be fairly said to have embraced the
proposition that the petitioner could return with the same
claims after they all had been exhausted. This latter propo-
sition could be thought to rest upon the theory that a petition
dismissed for lack of exhaustion is a petition that never ex-
isted, so that any other later petition would not be second
or successive. Or it could be thought to rest upon the the-
ory that the later refiling of the original claims, all of them
now exhausted, is just a renewal of the first petition, implic-
itly authorized by the dismissal to permit exhaustion. The
former theory is counterfactual; the latter is quite plausible.
The language the Court quotes from Rose and Martinez-
Villareal also does not justify the Court’s mixed-petitions-
don’t-count theory. The quotation from Rose says only that
“ ‘prisoners who . . . submit mixed petitions . . . are entitled
to . . . exhaust the remainder of their claims.’ ” Ante, at
486 (quoting Rose, supra, at 520 (emphasis added)). This
does not suggest that they are entitled to add new claims, or
to return, once again, without accomplishing the exhaustion
that the court dismissed the petition to allow. And the quo-
tation from Martinez-Villareal indicates only that when
a prisoner whose habeas petition was dismissed for failure
to exhaust state remedies “ ‘then did exhaust those reme-

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492 SLACK v. McDANIEL
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dies’ ” and refile in federal court, the court “ ‘could adjudicate
these claims under the same standard as would govern those
made in any other first petition.’ ” Ante, at 487 (quoting
Martinez-Villareal, 523 U. S., at 644 (emphasis added)).
This does not require treating the later filed petition as a
“first” petition regardless of whether it bears any resem-
blance to the petition initially filed. In fact, Martinez-
Villareal clearly recognized the potential significance of rais-
ing a new claim rather than merely renewing an old one: It
held that a petition raising a claim of incompetence to be
executed previously dismissed as premature was not second
or successive, but expressly distinguished, and left open, the
situation where the claim had not been raised in the earlier
petition. See id., at 645, n.
The State understandably fears the consequences of the
Court’s approach, which would allow federal petitions to be
repeatedly filed and dismissed for lack of exhaustion, requir-
ing the State repeatedly to appear and expend its resources,
with no help in sight from supposed limitations on “second
or successive” petitions. The Court reassuringly observes
that this problem can be countered in other ways, without
“upsetting the established meaning of a second or successive
petition.” Ante, at 489. But as discussed above, it is not
“established” that a first petition ceases to be a first petition
when it is dismissed to permit exhaustion. And though the
problem of repetitive filings after dismissals for lack of ex-
haustion can of course be countered in other ways, so can the
problem of repetitive filings for all other reasons. It hap-
pens to be the whole purpose of the “second or successive”
provision to solve precisely that problem—directly checking
the “vexatious litigant,” ante, at 488, rather than hoping that
the courts will use a patchwork of other provisions to achieve
the same end. I do not disagree with the Court that district
courts may be able to limit repeated filings through appro-
priate orders pursuant to Federal Rules of Civil Procedure
41(a) and (b). This burden on district courts would not be

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necessary, however—and the States would not be remanded
to reliance upon the discretion of district judges—if the limi-
tation on “second or successive” petitions were given its nat-
ural meaning.
Because I believe petitioner’s inclusion of new and un-
exhausted claims in his postexhaustion petition rendered it
second or successive, he is not entitled to a certificate of
appealability, and I would affirm the decision of the Court
of Appeals.