The majority opinion alters our existing habeas corpus procedures in two significant respects. First, in part III.B. of the opinion, the majority establishes a general rule that all habeas corpus claims must be raised in a single petition, and that when a party files successive petitions asserting different claims, all later petitions must justify the failure to assert the claims in the first petition. Second, in part III.C., the majority holds that when a petitioner raises claims that would have warranted relief had they been timely asserted in an initial petition, but which were untimely or were omitted without justification from an earlier petition, this court will grant relief only in extremely limited circumstances.
I agree with the majority’s first holding. Strong societal interests require the imposition of reasonable limits on successive petitions1 for habeas corpus. I disagree, however, with the second holding, the impact of which will fall with particular force on death row inmates. When a habeas petition by a prisoner under sentence of death raises claims that should have been raised earlier, the majority’s rigid standard, under which the petitioner must show that “no reasonable judge or jury” would have convicted the petitioner or returned a death verdict, will make it virtually impossible for this court ever to grant relief. I would adopt instead the test used by the Pennsylvania courts. Under that test, a court will consider a habeas corpus claim on its merits, even though the claim should have been asserted earlier, if the petitioner shows either factual innocence or procedural unfairness of such gravity that “no civilized society” can tolerate it. In my view, the Pennsylvania test, unlike the majority’s unreasonably narrow standard, properly accommodates the competing interests. It gives death penalty prisoners a needed incentive to assert all their habeas claims in a prompt and orderly fashion, yet permits the writ of habeas corpus to serve its traditional function as a flexible procedural remedy of last resort to prevent severe and manifest injustice.
*804I
The writ of habeas corpus, also known as the Great Writ, occupies a place of particular importance in our law. It is the last safeguard our judicial system provides for those members of society who have been convicted of a crime without a fair trial. When matters that do not appear in the trial record—such as defense counsel’s unjustified failure to present material evidence of innocence or lesser culpability, or the prosecution’s use of perjured testimony—have affected the outcome of the trial, habeas corpus offers the sole method by which an unjustly imprisoned inmate may obtain relief.
But the writ of habeas corpus is not without cost. Because the writ is a collateral attack on a final judgment of conviction,2 it may undermine the societal interest in finality of criminal proceedings, by permitting repeated review and reanalysis of convictions following trials that were fundamentally fair. If abused, the writ of habeas corpus can waste precious resources and cause public disrespect for the judgments of our criminal courts. Thus, when devising procedural rules to govern the manner in which habeas corpus petitions may be filed, this court must try to reconcile two conflicting goals: to maximize judicial power to grant redress to persons unjustly imprisoned or sentenced to death, while simultaneously protecting society’s interest in the finality of its judicial decisions.
One such procedural rule concerns the circumstances under which habeas petitioners are permitted to file a second petition after denial of the first one. This court has consistently held that the California judiciary should generally not entertain successive habeas petitions raising the same issue. (In re Martin (1987) 44 Cal.3d 1, 27, fn. 3 [241 Cal.Rptr. 263, 744 P.2d 374]; In re Rodriguez (1975) 14 Cal.3d 639, 654, fn. 18 [122 Cal.Rptr. 552, 537 P.2d 384]; In re Lynch (1972) 8 Cal.3d 410, 439, fn. 26 [105 Cal.Rptr. 217, 503 P.2d 921]; In re Terry (1971) 4 Cal.3d 911, 921, fn. 1 [95 Cal.Rptr. 31, 484 P.2d 1375]; In re Miller (1941) 17 Cal.2d 734, 735 [112 P.2d 10].) Until today, however, this court has not firmly established a similar rule barring *805successive petitions raising different issues.3 As the majority explains, there are valid and substantial reasons supporting such a rule. Successive habeas petitions are a drain on limited judicial resources; it is less cumbersome for courts to consider all claims at one time than to address them in piecemeal fashion. Also, prosecutorial agencies should not be required to expend scarce taxpayer dollars to repeatedly defend a presumptively valid final judgment. Most important, society has a strong interest in the finality of judgments rendered by its courts. As one legal scholar put it: “A procedural system which permits an endless repetition of inquiry into facts and law in a vain search for ultimate certitude implies a lack of confidence about the possibilities of justice that cannot but war with the effectiveness of the underlying substantive commands [punishing criminal acts]. . . . There comes a point where a procedural system which leaves matters perpetually open no longer reflects humane concern but merely anxiety and a desire for immobility.” (Bator, Finality in Criminal Law and Federal Habeas Corpus for State Prisoners (1963) 76 Harv. L.Rev. 441, 452-453.)
By adopting a rule that, whenever possible, all habeas claims must be raised in a single petition, this court does not unfairly burden those seeking relief. If a petitioner knows, or should know, of several possible grounds for relief, the petitioner should bring these grounds to the attention of the court at the same time. If a petitioner does file a successive petition raising new issues, it is reasonable to require the petitioner to explain the failure to raise those issues in a previous petition.
But if the habeas petitioner can justify the failure to raise in the previous petition the issues presented in the successive petition, the court should address the merits of those issues. For instance, an incarcerated inmate who is unrepresented by counsel and unaware of his or her legal rights may learn of a meritorious ground for relief only after unsuccessfully challenging the conviction on another ground. In that situation, the petitioner will have shown justification for the successive petition, thus warranting the court’s consideration of the merits of the petition. Based on my understanding that such consideration will indeed be permitted, I join part III.B. of the majority opinion.
II
I turn now to the difficult question of when this court should entertain a petition for writ of habeas corpus that, although meritorious, is either *806untimely or unjustifiably successive. This question is especially difficult when the petitioner, as in this case, has been sentenced to death. On the one hand, the state should not be permitted to put a person to death unless it has first given that person a fair trial. On the other hand, as I explain below, in capital cases the state has a particularly compelling need for rules that require the condemned prisoner to challenge the judgment in a timely manner.
Most defendants who challenge criminal convictions collaterally by means of a petition for writ of habeas corpus are prisoners who are serving their sentence in a penal institution. The hope of early release gives them a strong incentive to expedite the filing of a habeas petition, and they usually have little or nothing to gain by delaying the process. But for inmates on death row seeking habeas relief, the situation is otherwise. They, unlike other prisoners, have not yet begun to “serve” their sentence of death. Although a successful habeas petition by an incarcerated capital defendant may produce immediate benefits in the form of release from prison, retrial, or reduction of sentence, a court’s final rejection of all habeas issues generally removes the last judicial barrier to execution. Because courts may grant stays of execution during the pendency of habeas corpus proceedings, prisoners facing a death sentence may seek to prolong their lives by ensuring that such proceedings are never finally concluded. Thus, death row inmates have an incentive to delay assertion of habeas corpus claims that is not shared by other prisoners.
To encourage prospective petitioners, and particularly those with an incentive for delay, to raise all their habeas claims promptly and in a single petition, courts must devise standards that make relief less readily available when a petition is untimely or unjustifiably successive.4 But in fashioning an appropriate standard by which to judge these disfavored petitions, courts must be careful to preserve judicial authority to grant relief in cases of egregious illegality and gross injustice. To deny relief on procedural grounds to one who can persuasively demonstrate innocence, or whose guilt or punishment was determined in a manner that was grossly unfair, would betray traditional and deeply held convictions of our society. The need to preserve judicial authority to grant relief in these rare but deserving cases is particularly great in California, as I shall explain.
*807In California, a particular habeas petition may be found to be untimely even though the petitioner has no desire to misuse the judicial process. For instance, the petitioner, or the petitioner’s counsel, may believe in good faith that there are legitimate grounds for the delay in presenting the claim; the court, however, may find those grounds unpersuasive. Alternatively, the petitioner may raise a claim of which he or she was not, but should have been, aware at an earlier time. California courts may deny such a petition as untimely notwithstanding the petitioner’s intent to comply fully with the policies. Under the majority opinion, the rules I just mentioned will also apply to successive petitions filed without justification.
Today, the majority adopts a rule that an untimely petition, or a successive petition that is unjustified, will be considered only if it shows that the petitioner has been subjected to a “fundamental miscarriage of justice.” (Maj. opn., ante, p. 797.) The majority explains what it means by this term: a petitioner can obtain relief by showing “(1) 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; (2) that the petitioner is actually innocent. . . ; (3) that the death penalty was imposed by a sentencing authority which 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 (4) that the petitioner was convicted or sentenced under an invalid statute.” (Maj. opn., ante, pp. 759, 797-798, fns. omitted.)
I disagree with the majority’s definition of “fundamental miscarriage of justice.” The defects in the majority’s definition are particularly glaring when the majority’s “fundamental miscarriage of justice” test is applied to habeas petitions asserting irregularities at the penalty phase of a capital case. When the habeas petitioner is challenging the penalty phase, parts (1) and (2) of the majority’s test are inapplicable, because they relate to evidence of guilt, not penalty. Part (4) is similarly inapplicable, unless the petitioner can show that California’s death penalty law is invalid. Therefore, to prevail the petitioner would have to satisfy part (3) of the majority’s test: that “absent the trial error ... no reasonable judge or jury would have imposed a sentence of death.” For a habeas petitioner who has not diligently sought relief, this requirement poses a nearly insurmountable hurdle. In almost every case in which a defendant has committed an act of capital murder rendering him or her eligible for the death penalty, a judge or jury could reasonably conclude that the murder warrants the death penalty. Thus, it will be virtually impossible for a petitioner who has filed an untimely or unjustifiably successive habeas petition to satisfy the majority’s prerequisite for obtaining relief.
*808Three examples illustrate the undue harshness of the majority’s test when applied to challenges to the penalty phase of a capital trial. In each, the habeas petitioner has not been diligent in presenting the claim, but has been subjected to a fundamental miscarriage of justice. In each instance, the majority rule would apparently bar relief.
1. At the penalty phase of a capital trial, the prosecution’s only evidence in aggravation consists of proof that the defendant committed multiple uncharged acts of kidnap and rape. In a habeas petition the defendant shows conclusively that another person committed and was convicted of those crimes, and that the jury was thus presented with what the majority describes as a “grossly misleading profile” of the defendant. Yet a reasonable jury could, based on the circumstances of the capital offense alone, have imposed either a sentence of life without possibility of parole or a sentence of death.
2. At the penalty phase, the defendant’s trial counsel, without justification, fails to present mitigating evidence. Had counsel presented such evidence, it is more probable than not that the jury would have imposed a sentence of life without possibility of parole, but a reasonable jury could have imposed a sentence of death. (See, e.g., Deutscher v. Whitley (9th Cir. 1993) 991 F.2d 605.)
3. Several jurors in a capital trial accept bribes to give the defendant the death sentence. The evidence presented at the penalty phase of the trial is such that a reasonable jury could have imposed either a sentence of life without possibility of parole or a sentence of death.
Apparently, none of these three instances would warrant relief under the majority’s newly adopted test. I, however, am of the view that each of these illustrations demonstrates a “fundamental miscarriage of justice” of a magnitude that warrants relief even though the issue was raised in an untimely or an unjustifiably successive petition for writ of habeas corpus. When, as in the examples I have given, a defendant has been sentenced to death as a result of a trial that was egregiously unfair, to deny relief simply because the defendant’s challenge to the trial has not been diligent would be offensive to traditional notions of justice. I cannot accept the majority’s conclusion that the need to enforce our procedural rules is so great that we must deny relief even if the claim is as compelling as in the three examples I have given.
To enforce our procedural rules without sacrificing the power to remedy manifest injustice, this court should adopt a standard that would permit it to grant relief in the situations I have described, while at the same time creating a strong incentive for a petitioner to raise all claims in a diligent manner. *809Such a standard has been adopted in Pennsylvania. Under the Pennsylvania decisions, which the majority cites in support of its “fundamental miscarriage of justice” test (maj. opn., ante, pp. 792-793, 796), a successive habeas petition will be entertained only “if the petitioner can demonstrate either: (a) that the proceedings resulting in his conviction were so unfair that a miscarriage of justice occurred which no civilized society can tolerate or (b) that he [or she] is innocent of the criminal charges.” (Com. v. Laskaris (1991) 407 Pa.Super. 373 [595 A.2d 1229, 1231]; Com. v. Ryan (1990) 394 Pa.Super. 373 [575 A.2d 949, 950]; Com. v. Lawson (1988) 519 Pa. 504 [549 A.2d 107, 112].)
The majority deems the Pennsylvania test unsatisfactory because it is “not ... a rule capable of consistent application, and is not readily adaptable to penalty verdicts in capital cases.”5 (Maj. opn., ante, p. 796, fn. omitted.) But the majority offers no showing that Pennsylvania, which like California has a death penalty law (42 Pa. Cons. Stat. Ann. § 9711), has found its standard “not readily adaptable” to capital cases. Unlike the majority’s rigid rule, the Pennsylvania test enables the court to appropriately determine, when faced with the wide variety of issues that may arise on habeas corpus, whether the trial was so grossly unfair that the court should excuse the defendant’s lack of diligence. Better to tolerate a certain degree of ambiguity than to bind ourselves in a rigid framework that will preclude relief when it is clearly warranted.6
Ill
Today, the majority places new limits on the writ of habeas corpus, limits that will particularly affect death row prisoners. I agree with the majority *810that strong societal interests justify reasonable limits on successive petitions for habeas corpus that may, without such limits, indefinitely delay execution of valid and final death judgments. I also agree that this court should not entertain such petitions unless the petitioner has shown a fundamental miscarriage of justice—that is, an unfairness of the type that, as defined under the Pennsylvania test, “no civilized society can tolerate.” But the majority adopts a definition of “fundamental miscarriage of justice” that is unduly narrow and rigid. Consequently, this court may be compelled to deny relief to a defendant sentenced to death as a result of a grossly unfair trial, simply because the defendant ought to have brought the claim to us somewhat earlier. To preserve judicial authority to grant relief from judgments of death in the most deserving cases, I would use the standard devised and applied by the Pennsylvania courts.
Because in this case petitioner’s application for a writ of habeas corpus is untimely, and because petitioner has not shown a fundamental miscarriage of justice—under either the majority’s unyieldingly constrictive definition or the alternative definition I favor—I join in the majority’s denial of the petition.
Petitioner’s application for a rehearing was denied September 22, 1993. Mosk, J., and Kennard, J., were of the opinion that the application should be granted.
*811Appendix
Supreme Court Policies Regarding Cases Arising From Judgments of Death, Policy 3 (“Standards Governing Filing of Habeas Corpus Petitions and Compensation of Counsel In Relation to Such Petitions”), Part 1 (“Timeliness Standards”), last appearing in Pamphlet No. 2 of the 1993 Advance Sheets of the California Official Reports, Rules pages 3-7, is amended as follows [revised paragraphs are noted in brackets]:
3. Standards Governing Filing of Habeas Corpus Petitions and Compensation of Counsel in Relation to Such Petitions
The Supreme Court promulgates these standards as a means of implementing the following goals with respect to petitions for writs of habeas corpus relating to capital cases: (i) ensuring that potentially meritorious habeas corpus petitions will be presented to and heard by this court in a timely fashion; (ii) providing appointed counsel some certainty of payment for authorized legal work and investigation expenses; and (iii) providing this court with a means to monitor and regulate expenditure of public funds paid to counsel who seek to investigate and file habeas corpus petitions.
For these reasons, effective June 6, 1989, all petitions for writs of habeas corpus arising from judgments of death, whether the appeals therefrom are pending or previously resolved, are governed by these standards:
1. Timeliness standards
1-1. [Revised.] Appellate counsel in capital cases shall have a duty to investigate factual and legal grounds for the filing of a petition for a writ of habeas corpus. The duty to investigate is limited to investigating potentially meritorious grounds for relief that have come to counsel’s attention in the course of preparing the appeal. It does not impose on counsel an obligation to conduct, nor does it authorize the expenditure of public funds for, an unfocused investigation having as its object uncovering all possible factual bases for a collateral attack on the judgment. Instead, counsel has a duty to investigate potential habeas corpus claims only if counsel has become aware of information that might reasonably lead to actual facts supporting a claim. All petitions for writs of habeas corpus should be filed without substantial delay.
1-1.1 A petition for a writ of habeas corpus will be presumed to be filed without substantial delay if it is filed within 90 days after the final due date for the filing of appellant’s reply brief on the direct appeal.
1-1.2 [Revised.] A petition filed more than 90 days after the final due date for the filing of appellant’s reply brief on the direct appeal may establish absence of substantial delay if it alleges with specificity facts showing the petition was filed within a reasonable time after petitioner or counsel (a) knew, or should have known, of facts supporting a claim and (b) became aware, or should have become aware, of the legal basis for the claim.
1-1.3 Alternatively, a petition may establish absence of substantial delay if it alleges with specificity facts showing that although petitioner or counsel was aware of the factual and legal bases for the claim before January 16, 1986 (the date of finality of In re Stankewitz (1985) 40 Cal.3d 391, 396-397, fn. 1 [220 Cal.Rptr. 382, 384, fn. 1, 708 P.2d 1260, 1262, fn. 1]), the petition was filed within a reasonable time after that date.
1-2. If a petition is filed after substantial delay, the petitioner must demonstrate good cause for the delay. A petitioner may establish good cause by showing particular circumstances sufficient to justify substantial delay.
1- 3. Any petition that fails to comply with these requirements may be denied as untimely.
2. Compensation standards
2- 1. This court’s appointment of counsel for a person under a sentence of death is for the following: (i) pleadings and proceedings related to preparation and certification of the *812appellate record; (ii) representation in the direct appeal before the California Supreme Court; (iii) preparation and filing of habeas corpus petitions and other ancillary pleadings in the California Supreme Court; (iv) preparation and filing of a petition for a writ of certiorari, or an answer thereto, in the United States Supreme Court; (v) representation in the trial court relating to proceedings pursuant to Penal Code sections 1193 and 1227; and (vi) preparation and filing of a petition for clemency with the Governor of California no earlier than after exhaustion of the initial round of collateral challenges in federal court. Absent prior authorization by this court, this court will not compensate counsel for the filing of any other motion, petition, or pleading in any other California or federal court or court of another state. Counsel who seek compensation for representation in another court should secure appointment by, and compensation from, that court.
2-2. Appellate counsel should expeditiously investigate possible bases for filing a petition for a writ of habeas corpus. As a general rule, this investigation should be done concurrently with review of the appellate record and briefing on appeal. Requests by appointed counsel for authorization to incur, and reimbursement of, investigation expenses shall be governed by the following standards:
2-2.1 Without prior authorization of the court, counsel may incur expenses up to a total of $3,000 for habeas corpus investigation, and may submit to the court claims for reimbursement up to that amount. The court will reimburse counsel for expenses up to $3,000 that were reasonably incurred.
2-2.2 If after incurring $3,000 in expenses, counsel determines it is necessary to incur additional expenses for which he or she plans to seek reimbursement from the court, counsel must seek and obtain prior authorization from the court. As a general rule, the court will not reimburse counsel for expenses exceeding $3,000, without prior authorization of the court. Requests by appointed counsel for prior authorization of investigation expenses shall be governed by the following standards:
2-3. On or before the date the appellant’s opening brief on appeal is filed, counsel shall file with this court a “Confidential request for authorization to incur expenses to investigate potential habeas corpus issues.” The court will entertain an initial request filed at a later time only if good cause for the delay is shown.
2-4. The confidential request for authorization to incur expenses shall set out:
2-4.1 The issues to be explored;
2-4.2 Specific facts that suggest there may be an issue of possible merit;
2-4.3 An itemized list of the expenses requested for each issue of the proposed habeas corpus petition; and
2-4.4 (a) An itemized listing of all expenses previously sought from, and/or approved by any court of this state and/or any federal court in connection with any habeas corpus proceeding or investigation concerning the same judgment and petitioner; (b) A statement summarizing the status of any proceeding or investigation in any court of this state or any federal court concerning the same judgment and petitioner; and (c) A copy of any related petition previously filed in any trial or lower appellate court of this state or any federal court concerning the same judgment and petitioner.
2-5. Counsel generally will not be awarded compensation for fees and expenses relating to matters that are clearly not cognizable in a petition for a writ of habeas corpus.
2-6. Each request for fees relating to a habeas corpus petition must be accompanied by: (a) An itemized listing of all fees previously sought from, and/or approved by any court of this state and/or any federal court in connection with any habeas corpus proceeding or investigation concerning the same judgment and petitioner; (b) A statement summarizing the status of any proceeding or investigation in any court of this state or any federal court concerning the same judgment and petitioner; and (c) A copy of any related petition previously filed in any trial or lower appellate court of this state or any federal court concerning the same judgment and petitioner.
Although for convenience I refer throughout this opinion to successive and untimely “petitions,” I recognize that a habeas corpus petition may contain several claims for relief, some of which are untimely and some not, and that in a successive petition the petitioner may be able to justify his or her failure to raise some claims in the previous petition, but be unable to justify the failure to raise others. The court must examine the individual claims in such petitions, not the petition as a whole, to determine whether they are diligently raised.
This case involves solely claims raised on habeas corpus, not those raised on direct appeal. Habeas corpus permits a prisoner to raise a collateral attack on the legality of his or her confinement. Because issues that are or could be raised on appeal generally may not be raised on habeas corpus (In re Waltreus (1965) 62 Cal.2d 218, 225 [42 Cal.Rptr. 9, 397 P.2d 1001]; In re Dixon (1953) 41 Cal.2d 756, 759 [264 P.2d 513]), habeas corpus is most often used when, because the challenge to the legality of the commitment involves matters not shown in the appellate record, the petitioner’s appellate remedy is inadequate.
The majority points to language in several cases early in this century suggesting the existence of such a limitation. (Maj. opn., ante, pp. 767-768.) For almost 50 years, however, no published decision of any California court has acknowledged the existence of this limitation.
Until today we have not had such a standard. My research has disclosed no case discussing the circumstances in which a court will consider an untimely petition for writ of habeas corpus on its merits. Our decisions have noted that our policy barring successive petitions raising the same issue is “discretionary,” without explaining, however, when courts should exercise their discretion. (In re Terry (1971) 4 Cal.3d 911, 921, fn. 1 [95 Cal.Rptr. 31, 484 P.2d 1375]; In re Bevill (1968) 68 Cal.2d 854, 863, fn. 9 [69 Cal.Rptr. 599, 442 P.2d 679].) As I noted previously at pages 804-805, ante, until today there has been no firmly established rule in this state barring successive petitions that raise different issues.
The majority also contends that the Pennsylvania standard would “encourage" delay. (Maj. opn., ante, p. 796, fn. 31.) This assertion is puzzling, in view of the conclusion of the Pennsylvania courts that the standard has the opposite effect. The Pennsylvania standard may not be as effective a method of discouraging delay as the harsher test the majority adopts, but it strikes a fair balance between the need to redress gross injustice with the sometimes conflicting need to encourage compliance with procedural rules.
The majority borrows, in a slightly modified form, its “no reasonable jury would have voted for death” test from the United States Supreme Court’s decision in Sawyer v. Whitley (1992) 505 U.S._[120 L.Ed.2d 269, 112 S.Ct. 2514], But the federal courts, although they apply the Sawyer test to successive petitions filed without justification (id. at p. 467 [120 L.Ed.2d at pp. 278-279, 112 S.Ct. at p. 2518]; McCleskey v. Zant (1991) 499 U.S. 488-490 [113 L.Ed.2d 517, 541-542, 111 S.Ct. 1454, 1468]), use a different test when a habeas petition is untimely. In federal court, an untimely habeas petition will nevertheless be considered unless the government can show that the unnecessary delay has prejudiced its ability to respond to the petition. (Vasquez v. Hillery (1986) 474 U.S. 254, 265 [88 L.Ed.2d 598, 610, 106 S.Ct. 617]; 2 Liebman, Federal Habeas Corpus Practice and Procedure (1988) § 36.4, p. 555.) In contrast, California courts may deny a petition as untimely regardless of prejudice to the prosecution’s ability to respond to it. Thus, at least with respect to petitions that are untimely (as opposed to successive), the majority has adopted a more restrictive test * than that used in the federal courts.