with whom Mr. Justice Brennan joins, dissenting.
The Court today holds that the prosecutor’s constitutional duty to provide exculpatory evidence to the defense is not limited to cases in which the defense makes a request for such evidence. But once having recognized the existence of a duty to volunteer exculpatory evidence, the Court so narrowly defines the category of “material” evidence embraced by the duty as to deprive it of all meaningful content.
In considering the appropriate standard of materiality governing the prosecutor’s obligation to volunteer exculpatory evidence, the Court observes:
“[T]he fact that such evidence was available to the prosecutor and not submitted to the defense places it in a different category than if it had simply been *115discovered from a neutral source after trial. For that reason the defendant should not have to satisfy the severe burden of demonstrating that newly discovered evidence probably would have resulted in acquittal [the standard generally applied to a motion under Fed. Rule Crim. Proc. 33 based on newly discovered evidence 1]. If the standard applied to the usual motion for a new trial based on newly discovered evidence were the same when the evidence was in the State’s possession as when it was found in a neutral source, there would be no special significance to the prosecutor’s obligation to serve the cause of justice.” Ante, at 111 (footnote omitted).
I agree completely.
The Court, however, seemingly forgets these precautionary words when it comes time to state the proper standard of materiality to be applied in cases involving neither the knowing use of perjury nor a specific defense request for an item of information. In such cases, the prosecutor commits constitutional error, the Court holds, “if the omitted evidence creates a reasonable doubt that did not otherwise exist.” Ante, at 112. As the Court’s subsequent discussion makes clear, the defendant challenging the prosecutor’s failure to disclose evidence is entitled to relief, in the Court’s view, only if the withheld evidence actually creates a reasonable doubt as to guilt in the judge’s mind. The burden thus imposed on the defendant is at least as “severe” as, if not more *116“severe” than,2 the burden he generally faces on a Rule 33 motion. Surely if a judge is able to say that evidence actually creates a reasonable doubt as to guilt in his mind (the Court’s standard), he would also conclude that the evidence “probably would have resulted in acquittal” (the general Rule 33 standard). In short, in spite of its own salutary precaution, the Court treats the case in which the prosecutor withholds evidence no differently from the case in which evidence is newly discovered' from a neutral source. The “prosecutor’s obligation to serve the cause of justice” is reduced to a status, to borrow the Court’s words, of “no special significance.” Ante, at 111.
Our overriding concern in cases such as the one before us is the defendant’s right to a fair trial. One of the most basic elements of fairness in a criminal trial is that available evidence tending to show innocence, as well as that tending to show guilt, be fully aired before the jury; more particularly, it is that the State in its zeal to convict a defendant not suppress evidence that might exonerate him. See Moore v. Illinois, 408 U. S. 786, 810 (1972) (opinion of Marshall, J.). This fundamental notion of fairness does not pose any irreconcilable conflict for the prosecutor, for as the Court reminds us, the prosecutor “must always be faithful to his client’s overriding interest that ‘justice shall be done.’ ” Ante, at 111. No interest of the State is served, and no duty of the prosecutor advanced, by the suppression of evidence favorable to the defendant. On the contrary, the prosecutor fulfills his most basic responsibility when he fully airs all the relevant evidence at his command.
1 recognize, of course, that the exculpatory value to the defense of an item of information will often not be apparent to the prosecutor in advance of trial. And *117while the general obligation to disclose exculpatory information no doubt continues during the trial, giving rise to a duty to disclose information whose significance becomes apparent as the case progresses, even a conscientious prosecutor will fail to appreciate the significance of some items of information. See United States v. Keogh, 391 F. 2d 138, 147 (CA2 1968). I agree with the Court that these considerations, as well as the general interest in finality of judgments, preclude the granting of a new trial in every case in which the prosecutor has failed to disclose evidence of some value to the defense. But surely these considerations do not require the rigid rule the Court intends to be applied to all but a relatively small number of such cases.
Under today’s ruling, if the prosecution has not made knowing use of perjury, and if the defense has not made a specific request for an item of information, the defendant is entitled to a new trial only if the withheld evidence actually creates a reasonable doubt as to guilt in the judge’s mind. With all respect, this rule is completely at odds with the overriding interest in assuring that evidence tending to show innocence is brought to the jury’s attention. The rule creates little, if any, incentive for the prosecutor conscientiously to determine whether his files contain evidence helpful to the defense. Indeed, the rule reinforces the natural tendency of the prosecutor to overlook evidence favorable to the defense, and creates an incentive for the prosecutor to resolve close questions of disclosure in favor of concealment.
More fundamentally, the Court’s rule usurps the function of the jury as the trier of fact in a criminal case. The Court’s rule explicitly establishes the judge as the trier of fact with respect to evidence withheld by the prosecution. The defendant’s fate is sealed so long as the evidence does not create a reasonable doubt as to guilt in the judge’s mind, regardless of whether the *118evidence is such that reasonable men could disagree as to its import — regardless, in other words, of how “close” the case may be.3
The Court asserts that this harsh standard of materiality is the standard that “courts appear to have applied in actual cases although the standard has been phrased in different language.” Ante, at 113 (footnote omitted). There is no basis for this assertion. None of the cases cited by the Court in support of its statement suggests that a judgment of conviction should be sustained so long as the judge remains convinced beyond a reasonable doubt of the defendant’s guilt.4 The prevail*119ing view in the federal courts of the standard of materiality for cases involving neither a specific request for information nor other indications of deliberate misconduct — a standard with which the cases cited by the Court are fully consistent — is quite different. It is essentially the following: If there is a significant chance that the withheld evidence, developed by skilled counsel, would have induced a reasonable doubt in the minds of enough jurors to avoid a conviction, then the judgment of conviction must be set aside.5 This standard, unlike the Court’s, reflects a recognition that the determination must be in terms of the impact of an item of evidence on the jury, and that this determination cannot always be made with certainty.6
*120The Court approves — but only for a limited category of cases — a standard virtually identical to the one I have described as reflecting the prevailing view. In cases in which “the undisclosed evidence demonstrates that the prosecution’s case includes perjured testimony and that the prosecution knew, or should have known, of the perjury,” ante, at 103, the judgment of conviction must be set aside “if there is any reasonable likelihood that the false testimony could have affected the judgment of the jury.” Ibid. This lesser burden on the defendant is appropriate, the Court states, primarily because the withholding of evidence contradicting testimony offered by witnesses called by the prosecution “involve [s] a corruption of the truth-seeking function of the trial process.” Ante, at 104. But surely the truth-seeking process is corrupted by the withholding of evidence favorable to the defense, regardless of whether the evidence is directly contradictory to evidence offered by the prosecution. An example offered by Mr. Justice Fortas serves to illustrate the point. “[L]et us assume that the State possesses information that blood was found on the victim, and that this blood is of a type which does not match that of the accused or of the victim. Let us assume that no related testimony was offered by the State.” Giles v. Maryland, 386 U. S. 66, 100 (1967) (concurring in judgment). The suppression of the information unquestionably corrupts the truth-seeking process, and the burden on the defendant in establishing his entitlement to a new trial ought be no different from the burden he would face if related testimony had been elicited by the prosecution. See id., at 99-101.
The Court derives its “reasonable likelihood” standard for cases involving perjury from cases such as Napue v. *121Illinois, 360 U. S. 264 (1969), and Giglio v. United States, 405 U. S. 150 (1972). But surely the results in those cases, and the standards applied, would have been no different if perjury had not been involved. In Napue and Giglio, co-conspirators testifying against the defendants testified falsely, in response to questioning by defense counsel, that they had not received promises from the prosecution. The prosecution failed to disclose that promises had in fact been made. The corruption of the truth-seeking process stemmed from the suppression of evidence affecting the overall credibility of the witnesses, see Napue, supra, at 269; Giglio, supra, at 154, and that corruption would have been present whether or not defense counsel had elicited statements from the witnesses denying that promises had been made.
It may be that, contrary to the Court's insistence, its treatment of perjury cases reflects simply a desire to deter deliberate prosecutorial misconduct. But if that were the case, we might reasonably expect a rule imposing a lower threshold of materiality than the Court imposes— perhaps a harmless-error standard. And we would certainly expect the rule to apply to a broader category of misconduct than the failure to disclose evidence that contradicts testimony offered by witnesses called by the prosecution. For the prosecutor is guilty of misconduct when he deliberately suppresses evidence that is clearly relevant and favorable to the defense, regardless, once again, of whether the evidence relates directly to testimony given in the course of the Government’s case.
This case, however, does not involve deliberate prose-cutorial misconduct. Leaving open the question whether a different rule might appropriately be applied in cases involving deliberate misconduct,7 I would hold that the *122defendant in this case had the burden of demonstrating that there is a significant chance that the withheld evidence, developed by skilled counsel, would have induced a reasonable doubt in the minds of enough jurors to avoid a conviction. This is essentially the standard applied by the Court of Appeals, and I would affirm its judgment.
The burden generally imposed upon such a motion has also been described as a burden of demonstrating that the newly discovered evidence would probably produce a different verdict in the event of a retrial. See, e. g., United States v. Kahn, 472 F. 2d 272, 287 (CA2 1973); United States v. Rodriguez, 437 F. 2d 940, 942 (CA5 1971); United States v. Curran, 465 F. 2d 260, 264 (CA7 1972).
See United States v. Keogh, 391 F. 2d 138, 148 (CA2 1968), in which Judge Friendly implies that the standard the Court adopts is more severe than the standard the Court rejects.
To emphasize the harshness of the Court’s rule, the defendant’s fate is determined finally by the judge only if the judge does not entertain a reasonable doubt as to guilt. If evidence withheld by the prosecution does create a reasonable doubt as to guilt in the judge’s mind, that does not end the case — rather, the defendant (one might more accurately say the prosecution) is “entitled” to have the case decided by a jury.
In Stout v. Cupp, 426 F. 2d 881 (CA9 1970), a habeas proceeding, the court simply quoted the District Court’s finding that if the suppressed evidence had been introduced, “the jury would not have reached a different result.” Id., at 883. There is no indication that the quoted language was intended as anything more than a finding of fact, which would, quite obviously, dispose of the defendant’s claim under any standard that might be suggested. In Peterson v. United States, 411 F. 2d. 1074 (CA8 1969), the court appeared to require a showing that the withheld evidence “was ‘material’ and would have aided the defense.” Id., at 1079. The court in Lessard v. Dickson, 394 F. 2d 88 (CA9 1968), found it determinative that the withheld evidence “could hardly be regarded as being able to have much force against the inexorable array of incriminating circumstances with which [the defendant] was surrounded.” Id., at 91. The jury, the court noted, would not have been “likely to have had any [difficulty]” with the argument defense counsel would have made with the withheld evidence. Id., at 92. Finally, United States v. Tomaiolo, 378 F. 2d 26 (CA2 1967), required the defendant to show that the evidence was “material and of some substantial use to the defendant.” Id., at 28.
See, e. g., United States v. Morell, 524 F. 2d 550, 553 (CA2 1975); Ogden v. Wolff, 522 F. 2d 816, 822 (CA8 1975); Woodcock v. Amaral, 511 F. 2d 985, 991 (CA1 1974); United States v. Miller, 499 F. 2d 736, 744 (CA10 1974); Shuler v. Wainwright, 491 F. 2d 1213, 1223 (CA5 1974); United States v. Kahn, 472 F. 2d, at 287; Clarke v. Burke, 440 F. 2d 853, 855 (CA7 1971); Hamric v. Bailey, 386 F. 2d 390, 393 (CA4 1967).
That there is a significant difference between the Court's standards and what has been described as the prevailing view is made clear by Judge Friendly, writing for the court in United States v. Miller, 411 F. 2d 825 (CA2 1969). After stating the court's conclusion that a new trial was required because of the Government’s failure to disclose to the defense the pretrial hypnosis of its principal witness, Judge Friendly observed:
“We have reached this conclusion with some reluctance, particularly in light of the considered belief of the able and conscientious district judge, who has lived with this case for years, that review of the record in light of all the defense new trial motions left him ‘convinced of the correctness of the jury’s verdict.’ We, who also have had no small exposure to the facts, are by no means convinced otherwise. The test, however, is not how the newly discovered evidence concerning the hypnosis would affect the trial judge or ourselves but whether, with the Government’s case against [the defendant] already subject to serious attack, there was a significant chance that this added item, developed by skilled counsel as it *120would have been, could have induced a reasonable doubt in the minds of enough jurors to avoid a conviction. We cannot conscientiously say there was not.” Id., at 832 (footnote omitted).
It is the presence of deliberate prosecutorial misconduct and a desire to deter such misconduct, presumably, that leads the Court to recognize a rule more readily permitting new trials in cases in*122volving a specific defense request for information. The significance of the defense request, the Court states, is simply that it gives the prosecutor notice of what is important to the defense; once such notice is received, the failure to disclose is “seldom, if ever, excusable.” Ante, at 106. It would seem to follow that if an item of information is of such obvious importance to the defense that it could not have escaped the prosecutor’s attention, its suppression should be treated in the same manner as if there had been a specific request. This is precisely the approach taken by some courts. See, e. g., United States v. Morell, 524 F. 2d, at 553; United States v. Miller, 499 F. 2d, at 744; United States v. Kahn, 472 F. 2d, at 287; United States v. Keogh, 391 F. 2d, at 146-147.