OPINION OF THE COURT
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delivered the opinion of the Court.
This case concerns California’s time limitation on applications for postcon-viction (habeas corpus) relief. The question presented: Does California’s timeliness requirement qualify as an independent state ground adequate to bar habeas corpus relief in federal court?
California does not employ fixed statutory deadlines to determine the timeliness of a state prisoner’s petition for habeas corpus. Instead, California directs petitioners to file known claims “as promptly as the circumstances allow.” In re Clark,
California courts signal that a habeas petition is denied as untimely by citing the controlling decisions, i.e., Clark and Robbins. A spare order denying a petition without explanation or citation ordinarily ranks as a disposition on the merits. Tr. of Oral Arg. 7; see Harrington v. Richter, ante, at 99,
Petitioner below, respondent here, Charles W. Martin, presented the claims at issue—all alleging ineffective assistance of counsel—in a ha-beas petition filed in the California Supreme Court nearly five years after his conviction became final. He stated no reason for the long delay. Citing Clark and Robbins, the court denied Martin’s petition. In turn, the U. S. District Court for the Eastern District of California dismissed Martin’s federal habeas petition raising the same ineffective-assistance claims. Denial of Martin’s state-court petition as un
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adequate and independent state ground, i.e., Martin’s failure to seek relief in state court “without substantial delay.” See Robbins,
The U. S. Court of Appeals for the Ninth Circuit reversed the District Court’s decision. Contrasting the precision of “fixed statutory deadlines” with California’s proscription of “substantial delay,” the appeals court held that California’s standard lacked the clarity and certainty necessary to constitute an adequate state bar.
In a recent decision, Beard v. Kindler,
I
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While most States set determinate time limits for collateral relief applications, in California, neither statute nor rule of court does so. Instead, California courts “appl[y] a general ‘reasonableness’ standard” to judge whether a habeas petition is timely filed. Carey v. Saffold,
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Three leading decisions describe California’s timeliness requirement: Robbins, Clark, and In re Gallego,
California’s collateral review regime differs from that of other States
Because a habeas petitioner may skip over the lower courts and file directly in the California Supreme Court, In re Kler,
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of habeas petitions each year.
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In December 1986, Charles Martin participated in a robbery and murder in California. Martin fled the State, but eight years later he was extradited to California to stand trial. Convicted in state court of murder and robbery, Martin was sentenced to life in prison without the possibility of parole. In 1997, the California Court of Appeal affirmed his conviction and sentence, and the California Supreme Court denied review.
Martin initiated his first round of state habeas proceedings in 1998, and the next year, the California Supreme Court denied his petition. He then filed a habeas petition in the appropriate U. S. District Court. Finding that Martin’s federal petition included ineffective-assistance-of-counsel claims
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he had not aired in state court, the District Court stayed the federal proceedings pending Martin’s return to state court to exhaust his remedies there.
In March 2002, Martin filed his second habeas petition in the California Supreme Court, raising the federal ineffective-assistance claims his
Having exhausted state postconviction remedies, Martin returned to federal court and filed an amended petition. Based upon the California Supreme Court’s time-bar disposition, the District Court dismissed Martin’s belatedly asserted claims as procedurally precluded. Id., at 27, 57. The Ninth Circuit vacated the dismissal order and remanded the case, directing the District Court to determine the “adequacy” of the State’s time bar. Martin v. Hubbard,
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The Ninth Circuit again disagreed. Controlled by its prior decision in Townsend,
We granted certiorari,
II
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“A federal habeas court will not review a claim rejected by a state court ‘if the decision of [the state] court rests on a state law ground that is independent of the federal question and adequate to support the judgment.’ ” Kindler,
Ordinarily, a state prisoner seeking federal habeas relief must first “exhaus[t] the remedies available in the courts of the State,” 28 U.S.C.
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alleged violations of [the] prisoner’s federal rights,” Coleman,
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To qualify as an “adequate” procedural ground, a state rule must be “firmly established and regularly followed.” Kindler,
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California’s time rule, although discretionary, meets the “firmly established” criterion, as Kindler comprehended that requirement. The California Supreme Court, as earlier noted, framed the timeliness requirement for habeas petitioners in a trilogy of cases. See supra, at 312,
Martin nevertheless urges that California’s rule is too vague to be regarded as “firmly established.” “ [Reasonable time” period and “substantial delay,” he maintains, are “meaningless terms.” Brief for Respondent 48 (internal quotation marks omitted). We disagree. Indeterminate language is typical of discretionary rules. Application of those rules in particular circumstances, however, can supply the requisite clarity.
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Congressional statutes and this Court’s decisions, we note, have employed time limitations that are not stated in precise, numerical terms. Former Federal Habeas Corpus Rule 9(a), for example, set no fixed time limit on submission of habeas petitions. The Rule permitted dismissal of a state prisoner’s petition when it appeared that delay in commencing litigation “prejudiced [the State] in its ability to respond.” 28 U.S.C. § 2254 Rule 9(a) (1994 ed.). To stave off dismissal, the petitioner had to show that he could not earlier have known, “by the exercise of reasonable diligence,” the grounds on which he based the petition. Ibid. In Rhines v. Weber,
Current federal habeas prescriptions limit the time for filing a petition to one year. The clock runs from “the date on which the [supporting] facts . . . could have been discovered through the exercise of due diligence.” 28 U.S.C. § 2255(f)(4) (2006 ed., Supp. Ill) (applicable to federal prisoners); see § 2244(d)(1)(D) (2006 ed.) (similar provision applicable to state prisoners). “[D]ue diligence,” we have observed, “is an inexact measure of how much delay is too much.” Johnson v. United States,
Nor is California’s time rule vulnerable on the ground that it is not regularly followed. Each year, the California Supreme Court summarily denies hundreds of habeas petitions by citing Clark and Robbins. Brief for Appellant in
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No. 08-15752 (CA9), pp. 31-32. On the same day the court denied Martin’s petition, it issued 21 other Clark/Robbins summary denials. See Brief for Habeas Corpus Resource Center as Amicus Curiae 20. In reasoned opinions, too, California courts regularly invoke Clark, Rob
Martin argued below that California’s time bar is not regularly followed in this sense: Use of summary denials makes it “impossible to tell” why the California Supreme Court “decides some delayed petitions on the merits and rejects others as untimely” Brief for Appellant in No. 08-15752 (CA9), pp. 37-38. We see no reason to reject California’s time bar simply because a court may opt to bypass the Clark/Robbins assessment and summarily dismiss a petition on the merits, if that is the easier path. See, e.g., Strickland v. Washington,
The Ninth Circuit concluded that California’s time bar is not consistently applied because outcomes under the rule vary from case to case. See
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A discretionary rule ought not be disregarded automatically upon a showing of seeming inconsistencies.
A state ground, no doubt, may be found inadequate when “discretion has been exercised to impose novel and unforeseeable requirements without fair or substantial support in prior state law . . . .” 16B C. Wright, A. Miller, & E. Cooper, Federal Practice and Procedure § 4026, p. 386 (2d ed. 1996) (hereinafter Wright & Miller); see Prihoda,
“[S]ound procedure often requires discretion to exact or excuse compliance with strict rules,” 16B Wright & Miller § 4028, p. 403, and we have no cause to discourage standards allowing courts to exercise such discretion. As this Court
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observed in Kindler, if forced to choose between mandatory rules certain to be found “adequate,” or more supple prescriptions that federal courts may disregard as “inadequate,” “many States [might] opt for mandatory rules to avoid the high costs that come with plenary federal review.”
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Today’s decision, trained on California’s timeliness rule for habeas petitions, leaves unaltered this Court’s repeated recognition that federal courts must carefully examine state procedural requirements to ensure that they do not operate to discriminate against claims of federal rights. See Brown v. Western R. Co. of Ala.,
For the reasons stated, we find no inadequacy in California’s timeliness rule generally or as applied in Martin’s case.
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The judgment of the United States Court of Appeals for the Ninth Circuit is therefore reversed.
Notes
. A petition for habeas relief in a capital case is presumed to be filed without substantial delay if it is filed within 180 days after the final due date for the filing of [an] appellant’s reply brief on the direct appeal . . . California Supreme Court Policies Regarding Cases Arising Prom Judgments of Death, Policy 3, Standard 1-1.1 (2010).
. In fiscal year 2008-2009, the California Supreme Court issued dispositions in 3,258 original habeas actions. Judicial Council of California, 2010 Court Statistics Report, Statewide Caseload Trends, 1999-2000 Through 2008-2009, p. 6, http://www.courtinfo.ca.gov/reference/documents/ csr2010.pdf (as visited Feb. 15, 2011, and in Clerk of Court’s case file). During a similar time period, a total of 2,210 habeas cases were on this Court’s docket. See October Term 2008 Filings by Case Type (available in Clerk of Court’s case file).
. Rather than dismiss a petition containing both exhausted and unexhausted claims, “a district court might stay the petition and hold it in abeyance while the petitioner returns to state court to exhaust his previously unexhausted claims. Once the petitioner exhausts his state remedies, the district court will lift the stay and allow the petitioner to proceed in federal court.” Rhines v. Weber,
. We have also recognized a “limited category’’ of “exceptional cases in which exorbitant application of a generally sound rule renders the state ground inadequate to stop consideration of a federal question.’’ Lee v. Kemna,
. An untimely petition “will be entertained on the merits if the petitioner demonstrates (i) that error of constitutional magnitude led to a trial that was so fundamentally unfair that absent the error no reasonable judge or jury would have convicted the petitioner; (ii) that the petitioner is actually innocent of the crime or crimes of which he or she was convicted; (iii) that the death penalty was imposed by a sentencing authority that had such a grossly misleading profile of the petitioner before it that, absent the trial error or omission, no reasonable judge or jury would have imposed a sentence of death; or (iv) that the petitioner was convicted or sentenced under an invalid statute.’’ In re Robbins,
. See, e.g., In re Sanders,
. Closer inspection may reveal that “seeming ‘inconsistency [s]’ . . . are not necessarily . . . arbitrarly] or irrationa[l]." Thornburgh v. Abbott,
. See also 16B Wright & Miller § 4026, pp. 385-386 (“Precisely defined rules cannot take account of the gravity of a procedural failure, the strength of the excuses offered, or the importance of the procedural and substantive consequences of excusing or punishing the failure.’’).
