Concurring Separately:

I agree with the majority that this court’s opinion in Pettaway v. Plummer, 943 F.2d 1041 (9th Cir.1991), requires this panel to affirm the district court’s grant of Santama-ria’s habeas corpus petition. I write separately to explain why I believe that Pettaway was wrongly decided, and why this court should rehear this case en banc to overrule Pettaway .

I.

SANTAMARIAS TRIAL

To appreciate fully the issues involved, it is necessary to review the evidence presented to the jury that convicted Santamaría of murder.

People v. Santamaria, 8 Cal.4th 903, 908-09 , 35 Cal.Rptr.2d 624 , 884 P.2d 81 (1994).

The jury convicted Santamaría of murder, but found not true a sentence enhancement charge that he personally used a knife during commission of the crime. Id. at 909 , 35 Cal.Rptr.2d 624 , 884 P.2d 81 . Santamaría never confessed to the crime, and Nubia was the only witness who testified that he saw Santamaría stab Guadron. Id. Apart from Nubia’s testimony, the only other evidence linking Santamaría to Guadron’s murder was some jewelry that had been stolen from Gua-dron and that Nubla and Santamaría together delivered to a pawn shop. Id.

In light of the above, the jury’s dual findings — guilty of murder, but not true that Santamaría personally used a knife — initially appear inconsistent. However, there is no real inconsistency. Nubia, who plead guilty to being an accessory and cooperated with the prosecution, had a strong incentive to present his testimony in a fashion that pinned most of the blame on Santamaría, and downplayed his own culpability. Recognizing Nubia’s mixed motives, the jury may well have harbored a reasonable doubt as to who actually stabbed Guadron — perhaps Nubia, not Santamaría, was the actual stabber. 1 Such a reasonable doubt would explain the jury’s not true finding on the personal knife use allegation. 2

At the same time, the jury quite consistently may have been persuaded, beyond a reasonable doubt, that Santamaría participated actively in the murder. Under California law, the prosecution can obtain a murder conviction by proving beyond a reasonable doubt either: (A) that the defendant was the direct perpetrator (the “direct perpetrator” theory); or (B) that the defendant was an aider and abettor (the “aider and abettor” theory); or (C) that the defendant was either a perpetrator or an aider and abettor (the “either/or” theory). Id. at 918-21 , 35 Cal.Rptr.2d 624 , 884 P.2d 81 . 3 “As long as each *1359 juror is convinced beyond a reasonable doubt that defendant is guilty of murder ... the jury need not decide unanimously whether defendant was guilty as the aider and abettor or as the direct perpetrator.” Id. at 918 , 35 Cal.Rptr.2d 624 , 884 P.2d 81 . Thus, if the jury was convinced that Nubla and Santama-ría together murdered Guadron, but the jury harbored a reasonable doubt as to who actually stabbed Guadron, it would be entirely appropriate for the jury to decide, as it did: (1) that Santamaría was guilty of murder; and (2) that the prosecutor failed to prove the personal knife use allegation beyond a reasonable doubt.

II.

HOW THIS CASE SHOULD BE ANALYZED ABSENT PETTAWAY

I begin my analysis with Ashe v. Swenson. There the Supreme Court held that collateral estoppel is “a part of the Fifth Amendment’s guarantee against double jeopardy.” 397 U.S. 436, 442 , 90 S.Ct. 1189, 1193-94 , 25 L.Ed.2d 469 (1970). The Court defined collateral estoppel as follows: “when an issue of ultimate fact has once been determined by a valid and final judgment, that issue cannot again be litigated between the same parties in any future lawsuit.” Ashe, 397 U.S. at 443 , 90 S.Ct. at 1194 . The party seeking to preclude relitigation of an issue bears the burden of proving “that the issue whose relit-igation he seeks to foreclose was actually decided in his favor” in the first proceeding. Schiro v. Farley, 510 U.S. 222, 236 , 114 S.Ct. 783, 792 , 127 L.Ed.2d 47 (1994) (quoting Dowling v. United States, 493 U.S. 342, 350 , 110 S.Ct. 668, 673 , 107 L.Ed.2d 708 (1990)) (internal quotations omitted).

In the present case, the petitioner contends that there are two distinct issues that the prosecution is collaterally estopped from litigating at retrial. First, the prosecution is precluded from arguing at retrial that Santa-maría personally stabbed Guadron (the direct perpetrator theory). I agree. By rendering a not true finding on the sentence enhancement allegation, the jury at the initial trial “actually decided,” Schiro, 510 U.S. at 236 , 114 S.Ct. at 792 , that the prosecution failed to prove Santamaria’s personal use of the knife beyond a reasonable doubt. “Having received one fair opportunity to offer whatever proof it could assemble, the State is not entitled to another.” Bullington v. Missouri, 451 U.S. 430, 446 , 101 S.Ct. 1852, 1862 , 68 L.Ed.2d 270 (1981) (citations omitted).

Second, petitioner also contends that the prosecution is collaterally estopped from litigating the either/or theory at retrial. I disagree. Although petitioner acknowledges that collateral estoppel does not bar the prosecution from attempting to prove at retrial that Santamaría was an aider and abettor, 4 he contends that the prosecution is barred from attempting to prove that Santamaría was either the direct perpetrator or the aider and abettor. To prevail on this claim, petitioner must prove that the jury at the initial trial “actually decided” the either/or theory in his favor. Schiro, 510 U.S. at 233-36 , 114 S.Ct. at 791-92 . In other words, petitioner must prove: (a) that the prosecutor at the first trial presented the either/or theory to *1360 the jury; (b) the jury considered the theory; and (c) the jury expressly rejected the theory.

Petitioner cannot sustain this argument. The jury found Santamaría guilty of murder. Under California law, the guilty verdict means that the jury was persuaded beyond a reasonable doubt that Santamaría was either: (a) the direct perpetrator, or (b) an aider and abettor, or (c) either the direct perpetrator or an aider and abettor. See Santamaria, 8 Cal.4th at 918-21 , 35 Cal.Rptr.2d 624 , 884 P.2d 81 . The jury cannot have relied on the direct perpetrator theory because that would be inconsistent with its not true finding on the personal knife use allegation. It follows that, to support its verdict, the jury must have relied either on the aider and abettor theory, or the either/or theory.

Petitioner, however, argues that the jury must have relied on the aider and abettor theory, and rejected the either/or theory, because that theory is inconsistent with the not true finding on the personal knife use charge. This argument is false. There is no inconsistency between the either/or theory and the not true finding. The jury could have harbored a reasonable doubt as to who actually stabbed Guadron, but been persuaded beyond a reasonable doubt that: (a) Nubia and Santamaría together murdered Gua-dron, and (b) either Nubla or Santamaría was the actual stabber. Indeed, the California Supreme Court concluded that this is the most plausible explanation for the jury’s actions. San tamaria, 8 Cal.4th at 919 , 35 Cal.Rptr.2d 624 , 884 P.2d 81 .

Aside from arguing the alleged inconsistency between the not true finding and the either/or theory, petitioner has failed to demonstrate that the jury expressly rejected the either/or theory. Thus, petitioner has failed to bear his burden of proving that the either/or theory “has once been determined by a valid and final judgment” in his favor. Ashe, 397 U.S. at 443 , 90 S.Ct. at 1194 . Were it not for Pettaway , I would hold that the prosecution is not collaterally estopped from arguing the either/or theory at Santa-maria’s retrial.

III.

THE PETTAWAY CASE

My argument that Pettaway was wrongly decided commences with the California Supreme Court statement that this court’s opinion “misunderstood the relevant state law.” Santamaria, 8 Cal.4th at 923, 35 Cal.Rptr.2d 624 , 884 P.2d 81 . Accordingly, the California Supreme Court urged this court to reconsider its decision. Id. at 925 , 35 Cal.Rptr.2d 624 , 884 P.2d 81 . I submit that the California Supreme Court was correct in its assessment of Pettaway .

In Pettaway , like Santamaría, the jury convicted the defendant of murder, but found “not true” a sentence enhancement charge that he personally used a deadly weapon (in his case a gun) to commit the murder. Pettaway, 943 F.2d at 1043 . The California Court of Appeal in Pettaway reversed the murder conviction, due to a flaw in the jury instructions. Id. On remand, Pettaway argued that collateral estoppel precluded the prosecution from advancing a theory that he personally fired the murder weapon (the direct perpetrator theory). Id. The trial court agreed, but the California Court of Appeal reversed. People v. Pettaway, 206 Cal.App.3d 1312 , 254 Cal.Rptr. 436 (1 Dist. 1988). The California Supreme Court denied review. Pettaway, 943 F.2d at 1043 . Petta-way then filed a petition for a writ of habeas corpus in federal district court. The district court denied Pettaway’s petition, and we reversed. Id.

We stated our holding as follows:

Id. at 1048 . In other words, we held that collateral estoppel bars retrial on a direct perpetrator theory, but does not bar retrial on an aider and abettor theory. Our holding, however, was silent as to whether collateral *1361 estoppel bars retrial on an either/or theory. Therefore, the Pettaway court erred by granting Pettaway’s habeas petition without deciding whether the prosecution was collaterally estopped from arguing an either/or theory at retrial.

Judge Wallace, in describing the Pettaway opinion, states: (1) that the district court relied on the either/or theory in denying Pettaway’s habeas petition; and (2) that in Pettaway there was discussion of the either/or theory. See op. at 1855 (citing Petta-way, 943 F.2d at 1044 ). Nonetheless, the Pettaway court reversed the district court’s order, and remanded with instructions to issue the writ of habeas corpus. Pettaway, 943 F.2d at 1048 . Therefore, it is possible to infer that the Pettaway court decided that the prosecution was collaterally estopped from arguing an either/or theory at retrial. Such an inference, however, is an incorrect application of collateral estoppel.

The district court in Pettaway stated its holding as follows: “[I]t is clear to the court that the sentence enhancement findings should not invoke collateral estoppel and prevent Petitioner from being retried on the theory that he personally shot Ms. Taylor.” That is, the district court held that the prosecution was not collaterally estopped from arguing a direct perpetrator theory at retrial. That holding was erroneous. By reversing the district court, this court held only that the prosecution was collaterally estopped from arguing a direct perpetrator theory at retrial. That holding was correct. However, Pettaway did not hold, and it would be erroneous for us to hold, that the prosecution is collaterally estopped from arguing an either/or theory at retrial.

Apart from the single paragraph in which Pettaway quoted the relevant language from the district court opinion, id. at 1044, its analysis reflects no proper recognition that the either/or theory constitutes a third possible ground for convicting a defendant of murder under California law. The entire analysis appears premised on an unstated assumption that there are only two possible theories (a direct perpetrator theory or an aider and abettor theory) that can support a murder conviction under California law. Thus, the California Supreme Court was correct when it stated that Pettaway “misunderstood the relevant state law.” Santamaria, 8 Cal.4th at 923 , 35 Cal.Rptr.2d 624 , 884 P.2d 81 .

The Pettaway court’s “misunderstanding” is evident in the manner in which it characterized Pettaway’s petition: “The basis for Pettaway’s petition is that his reprosecution on the theory that he shot Taylor is barred” by collateral estoppel. Pettaway, 943 F.2d at 1043 . This statement suggests that the court understood Pettaway’s petition to present a single claim: that the prosecution was collaterally estopped from arguing a direct perpetrator theory at retrial. If so, it failed to recognize that Pettaway’s petition also presented an additional claim: that the prosecution was collaterally estopped from arguing an either/or theory at retrial.

Moreover, in the very next sentence, the probability of this failure is strengthened. The court said: “To resolve this claim, we must first determine whether the jury’s finding that Pettaway did not personally shoot Taylor has collateral estoppel effect.” Id. In framing the collateral estoppel issue in this manner, the Pettaway court ignored another possibility. The not true finding on the personal weapon use allegation, properly understood, means only that the prosecution failed to prove beyond a reasonable doubt that Pettaway personally shot Taylor. The jury, however, might well have believed that it was more likely than not that Pettaway did shoot Taylor. All that is known for certain is that the prosecution failed to prove beyond a reasonable doubt that Pettaway personally shot Taylor.

The Pettaway court’s conclusion, to repeat, flows naturally from its erroneous assumption that the only two possibilities for sustaining a murder conviction were the direct perpetrator theory and the aider and abettor theory. Under that assumption, Pettaway’s murder conviction must rest on the aider and abettor theory. From that it follows that the jury found that “Pettaway did not personally shoot Taylor,” inasmuch as an aider and abettor cannot also be a perpetrator. Thus, to repeat, the language the Pettaway court used to describe the jury’s finding strongly *1362 suggests that the Pettaway court failed to recognize properly that the either/or theory is a third possibility under California law.

Having both misstated the nature of Petta-way’s claim, and misinterpreted the meaning of the jury’s not true finding, the next paragraph of the Pettaway opinion states:

Id. at 1043-44 (quoting United States v. Hernandez, 572 F.2d 218, 220 (9th Cir.1978)). The court then skipped over step one without any discussion, and proceeded immediately to step two, concluding that “the question whether Pettaway fired the gun himself was actually litigated at the first trial.” Id. at 1044. By skipping step one, and stating its conclusion with respect to step two in terms of the direct perpetrator theory (“whether Pettaway fired the gun himself’), the court again indicated that the only issue to be decided was whether collateral estoppel precluded the prosecution from relitigating the direct perpetrator theory at retrial. Again the court failed to consider whether the either/or theory had been litigated at the first trial, or whether the prosecution was barred from litigating that theory at the second trial.

The Pettaway court, confronted with a conviction for murder and a not true finding on the personal use allegation, harmonized the two by stating: “[T]here is a rational explanation that takes into account the whole of the jury’s verdict____ [Pettaway] could be guilty of first degree murder as long as he aided and abetted the murderer.” Id. at 1046. Once more the court failed to consider the possibility that Pettaway could be guilty of murder under an either/or theory.

Nothing in the remainder of the opinion undermines this conclusion. The Pettaway court “misunderstood the relevant state law,” Santamaria, 8 Cal.4th at 923 , 35 Cal.Rptr.2d 624 , 884 P.2d 81 , not in the sense that its holding was contrary to California law, but in the sense that it granted the habeas petition without deciding whether collateral estoppel barred retrial on an either/or theory. The Pettaway court’s failure to decide that issue was based on its failure to recognize that, under California law, a defendant can be convicted of murder on an either/or theory, even though “[t]here may be a reasonable doubt that the defendant was the direct perpetrator, and a similar doubt that he was the aider and abettor, but no such doubt that he was one or the other.” Id. at 919, 35 Cal.Rptr.2d 624 , 884 P.2d 81 .

IV.

SCOPE OF COLLATERAL ESTOPPEL

Pettaway should have held that collateral estoppel bars relitigation of a direct perpetrator theory, but does not bar the prosecution from arguing an either/or theory at retrial. Collateral estoppel should not preclude the prosecution from litigating an either/or theory at retrial, because a conviction under that theory would be consistent with the first jury’s not true finding on the sentence enhancement charge. Judge Wallace is correct when he points out that “[o]ur opinion in Pettaway does not contain a fully persuasive response” to this argument. Majority op. at 1356. There is no logical inconsistency between: (1) the first jury’s finding that the prosecution failed to prove personal weapon use beyond a reasonable doubt; and (2) a potential finding by a subsequent jury that the prosecution succeeded in proving beyond a reasonable doubt that the defendant was either a direct perpetrator or an aider and abettor.

Judge Wallace points out that Pettaway “may have rejected [a] technical, legalistic conception of ‘inconsistency.’ ” Majority op. at 1356. In other words, Pettaway may have decided, as a matter of federal law, that two jury findings could be “inconsistent” for purposes of collateral estoppel doctrine, even when there was no logical inconsistency between them.

*1363 Such an interpretation of collateral estop-pel is at odds with Ashe. There, the Court defined collateral estoppel to mean “that when an issue of ultimate fact has once been determined by a valid and final judgment, that issue cannot again be litigated between the same parties in any future lawsuit.” 397 U.S. at 443 , 90 S.Ct. at 1194 (emphasis added). The Court did not say that a closely related issue cannot be litigated in a future lawsuit. To bar the litigation of a closely related issue, the resolution of which involves no logical inconsistency with an earlier verdict, would effectively expand the Ashe collateral estoppel doctrine. To grant Santama-ria’s habeas petition would expand Ashe, without offering any guidance as to its limits. How “closely related” is “close enough” is an issue not likely to promote certainty in the law.

To repeat, the “not true” finding on- the personal knife use charge shows only that the prosecution at the initial trial failed to prove beyond a reasonable doubt that Santa-maría personally wielded the murder weapon. There was no finding that the prosecution failed to prove beyond a reasonable doubt that Santamaría was either a direct perpetrator or an aider and abettor. The latter is not the same issue as that resolved by the “not true” finding. Until today, no federal appellate court has interpreted the Ashe collateral estoppel doctrine to mean that a jury decision on the first issue bars a subsequent jury from considering the second issue.

V.

CONCLUSION

We should rehear this case en banc to consider whether Pettaway should be overruled. But for Pettaway, the habeas corpus petition before us should be denied.

.The California Supreme Court put it this way: Defendant ... argues that the jury did reach a unanimous verdict; it unanimously found the knife-use allegation not true. This is correct, but is of far less significance than defendant contends. It shows only that there was a reasonable doubt in the minds of the jurors that defendant specifically used a knife. It does not show the reverse, that the jury specifically found defendant was an aider and abettor. Indeed, under the facts of this case, such a finding is most unlikely. The jury may merely have believed, and most likely did believe, that defendant was guilty of murder as either a personal knife user or an aider and abettor but it may have been uncertain exactly which role defendant played. That, too, would fully explain, and necessitate, the split verdict.

Not only is there no unanimity requirement as to the theory of guilt, the individual jurors themselves need not choose among the theories, so long as each is convinced of guilt. Sometimes, as probably occurred here, the jury simply cannot decide beyond a reasonable doubt exactly who did what. There may be a reasonable doubt that the defendant was the direct perpetrator, and a similar doubt that he was the aider and abettor, but no such doubt that he was one or the other.

Santamaria, 8 Cal.4th at 919 , 35 Cal.Rptr.2d 624 , 884 P.2d 81 .

. Under California Penal Code Section 12022, a defendant’s sentence may be enhanced only if the juiy finds beyond a reasonable doubt that the defendant personally used a weapon. Santamaria, 8 Cal.4th at 918 , 35 Cal.Rptr.2d 624 , 884 P.2d 81 .

. The California Supreme Court stated the following:

Santamaria, 8 Cal.4th at 920-21 , 35 Cal.Rptr.2d 624 , 884 P.2d 81 (citations omitted).

. The prosecution has stated that it is unable to proceed on an aider and abettor theory at retrial. To prove that Santamaría was an aider and abettor, the prosecution would have to prove that Nubia was the direct perpetrator, and the prosecution lacks evidence to support such a charge.