667 MARSHALL, J., dissenting bias simply may not be said to be irrelevant, or its omission harmless. As THE CHIEF JUSTICE said in Giglio v. United States, in which the Court ordered a new trial in a case in which a promise to a key witness was not disclosed to the jury: "[W]ithout [Taliento's testimony] there could have been no indictment and no evidence to carry the case to the jury. Taliento's credibility as a witness was therefore an important issue in the case, and evidence of any understanding or agreement as to a future prosecution would be relevant to his credibility and the jury was entitled to know of it. "For these reasons, the due process requirements enunciated in Napue and other cases cited earlier require a new trial." Id., at 154-155. Here, too, witnesses O'Connor and Mitchell were crucial to the Government's case. Here, too, their personal credibility was potentially dispositive, particularly since the allegedly corroborating tape recordings were not audible. It simply cannot be denied that the existence of a contract signed by those witnesses, promising a reward whose size would depend "on the Government's satisfaction with the end result," ante, at 683, might sway the trier of fact, or cast doubt on the truth of all that the witnesses allege. In such a case, the trier of fact is absolutely entitled to know of the contract, and the defense counsel is absolutely entitled to develop his case with an awareness of it. Whatever the applicable standard of materiality, see infra, in this instance it undoubtedly is well met. Indeed, Giglio essentially compels this result. The similarities between this case and that one are evident. In both cases, the triers of fact were left unaware of Government inducements to key witnesses. In both cases, the individual trial prosecutors acted in good faith when they failed to disclose the exculpatory evidence. See Giglio, supra, at 151153; App. to Pet. for Cert. 13a (Magistrate's finding that MARSHALL, J., dissenting 473 U. S. Bagley prosecutor would have disclosed information had he known of it). The sole difference between the two cases lies in the fact that in Giglio, the prosecutor affirmatively stated to the trier of fact that no promises had been made. Here, silence in response to a defense request took the place of an affirmative error at trial-although the prosecutor did make an affirmative misrepresentation to the defense in the affidavits. Thus, in each case, the trier of fact was left unaware of powerful reasons to question the credibility of the witnesses. "[T]he 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." Agurs, supra, at 120 (MARSHALL, J., dissenting). In this case, as in Giglio, a new trial is in order, and the Court of Appeals correctly reversed the District Court's denial of such relief. II Instead of affirming, the Court today chooses to reverse and remand the case for application of its newly stated standard to the facts of this case. While I believe that the evidence at issue here, which remained undisclosed despite a particular request, undoubtedly was material under the Court's standard, I also have serious doubts whether the Court's definition of the constitutional right at issue adequately takes account of the interests this Court sought to protect in its decision in Brady v. Maryland, 373 U. S. 83 (1963). A I begin from the fundamental premise, which hardly bears repeating, that "[t]he purpose of a trial is as much the acquittal of an innocent person as it is the conviction of a guilty one." Application of Kapatos, 208 F. Supp. 883, 888 (SDNY 1962); see Giles v. Maryland, 386 U. S. 66, 98 (1967) (Fortas, J., concurring in judgment) ("The State's obligation is not to convict, but to see that, so far as possible, truth emerges"). When evidence favorable to the defendant is known to exist, 667 MARSHALL, J., dissenting disclosure only enhances the quest for truth; it takes no direct toll on that inquiry. Moreover, the existence of any small piece of evidence favorable to the defense may, in a particular case, create just the doubt that prevents the jury from returning a verdict of guilty. The private whys and wherefores of jury deliberations pose an impenetrable barrier to our ability to know just which piece of information might make, or might have made, a difference. When the state does not disclose information in its possession that might reasonably be considered favorable to the defense, it precludes the trier of fact from gaining access to such information and thereby undermines the reliability of the verdict. Unlike a situation in which exculpatory evidence exists but neither the defense nor the prosecutor has uncovered it, in this situation the state already has, resting in its files, material that would be of assistance to the defendant. With a minimum of effort, the state could improve the real and apparent fairness of the trial enormously, by assuring that the defendant may place before the trier of fact favorable evidence known to the government. This proposition is not new. We have long recognized that, within the limit of the state's ability to identify so-called exculpatory information, the state's concern for a fair verdict precludes it from withholding from the defense evidence favorable to the defendant's case in the prosecutor's files. See, e. g., Pyle v. Kansas, 317 U. S. 213, 215-216 (1942) (allegation that imprisonment resulted from perjured testimony and deliberate suppression by authorities of evidence favorable to him "charge a deprivation of rights guaranteed by the Federal Constitution").' 'As early as 1807, this Court made clear that prior to trial a defendant must have access to impeachment evidence in the Government's possession. Addressing defendant Aaron Burr's claim that he should have access to the letter of General Wilkinson, a key witness against Burr in his trial for treason, Chief Justice Marshall wrote: "The application of that letter to the case is shown by the terms in which the communication was made. It is a statement of the conduct of the MARSHALL, J., dissenting 473 U. S. This recognition no doubt stems in part from the frequently considerable imbalance in resources between most criminal defendants and most prosecutors' offices. Many, perhaps most, criminal defendants in the United States are represented by appointed counsel, who often are paid minimal wages and operate on shoestring budgets. In addition, unlike police, defense counsel generally is not present at the scene of the crime, or at the time of arrest, but instead comes into the case late. Moreover, unlike the government, defense counsel is not in the position to make deals with witnesses to gain evidence. Thus, an inexperienced, unskilled, or unaggressive attorney often is unable to amass the factual support necessary to a reasonable defense. When favorable evidence is in the hands of the prosecutor but not disclosed, the result may well be that the defendant is deprived of a fair chance before the trier of fact, and the trier of fact is deprived of the ingredients necessary to a fair decision. This grim reality, of course, poses a direct challenge to the traditional model of the adversary criminal process, and perhaps accused made by the person who is declared to be the essential witness against him. The order for producing this letter is opposed: "First, because it is not material to the defense. It is a principle, universally acknowledged, that a party has a right to oppose to the testimony of any witness against him, the declarations which that witness has made at other times on the same subject. If he possesses this right, he must bring forward proof of those declarations. This proof must be obtained before he knows positively what the witness will say; for if he waits until the witness has been heard at the trial, it is too late to meet him with his former declarations. Those former declarations, therefore, constitute a mass of testimony, which a party has a right to obtain by way of precaution, and the positive necessity of which can only be decided at the trial." United States v. Burr, 25 F. Cas. 30, 36 (No. 14,692d) (CC Va. 1807). See Fortas, The Fifth Amendment: Nemo Tenetur Prodere Seipsum, 25 Clev. B. A. J. 91, 98 (1954) (“The state and [the defendant] could meet, as the law contemplates, in adversary trial, as equals-strength against strength, resource against resource, argument against argument"); see also Babcock, Fair Play: Evidence Favorable to an Accused and Effective Assistance of Counsel, 34 Stan. L. Rev. 1133, 1142-1145 (1982) (discussing challenge Brady poses to traditional adversary model). T 667 MARSHALL, J., dissenting because this reality so directly questions the fairness of our longstanding processes, change has been cautious and halting. Thus, the Court has not gone the full road and expressly required that the state provide to the defendant access to the prosecutor's complete files, or investigators who will assure that the defendant has an opportunity to discover every existing piece of helpful evidence. But cf. Ake v. Oklahoma, 470 U. S. 68 (1985) (access to assistance of psychiatrist constitutionally required on proper showing of need). Instead, in acknowledgment of the fact that important interests are served when potentially favorable evidence is disclosed, the Court has fashioned a compromise, requiring that the prosecution identify and disclose to the defendant favorable material that it possesses. This requirement is but a small, albeit important, step toward equality of justice." B Brady v. Maryland, 373 U. S. 83 (1963), of course, established this requirement of disclosure as a fundamental element of a fair trial by holding that a defendant was denied due process if he was not given access to favorable evidence that is material either to guilt or punishment. Since Brady was decided, this Court has struggled, in a series of decisions, to define how best to effectuate the right recognized. To my mind, the Brady decision, the reasoning that underlay it, and the fundamental interest in a fair trial, combine to give the criminal defendant the right to receive from the prosecutor, and the prosecutor the affirmative duty to turn 'Indeed, this Court's recent decision stating a stringent standard for demonstrating ineffective assistance of counsel makes an effective Brady right even more crucial. Without a real guarantee of effective counsel, the relative abilities of the state and the defendant become even more skewed, and the need for a minimal guarantee of access to potentially favorable information becomes significantly greater. See Strickland v. Washington, 466 U. S. 668 (1984); id., at 712-715 (MARSHALL, J., dissenting); Babcock, supra, at 1163-1174 (discussing the interplay between the right to Brady material and the right to effective assistance of counsel). |