Fourteenth Amendment, Section 1:

All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside. No State shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States; nor shall any State deprive any person of life, liberty, or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws.

Beyond the general rule that the prosecution must prove a criminal defendant’s guilt beyond a reasonable doubt,1 the Due Process Clause also imposes certain limitations on specific evidentiary matters in criminal trials. For instance, a court may not restrict the basic due process right to testify in one’s own defense by automatically excluding hypnotically refreshed testimony.2 And, though a state may require a defendant to give pretrial notice of an intention to rely on an alibi defense and to furnish the names of supporting witnesses, due process calls for reciprocal discovery in such circumstances, requiring the state to give the defendant pretrial notice of its rebuttal evidence on the alibi issue.3

In evaluating whether certain procedures satisfy due process, the Court may consider how separate procedures interact. The combination of otherwise acceptable rules of criminal procedure may in some instances deny a defendant due process. Thus, in one case, the Court found that a defendant was denied his constitutional right to present his defense in a meaningful way by the combination of two rules that (1) denied the defendant the right to cross-examine his own witness in order to elicit exculpatory evidence and (2) denied him the right to introduce the testimony of witnesses about matters told to them out of court on the ground that the testimony would be hearsay.4 Conversely, a questionable procedure may be saved by its combination with another. Thus, in another case, the Court held that it does not deny a defendant due process to subject him to trial before a non-lawyer police court judge when he can obtain a later trial de novo in the state’s court system.5

The government violates the Due Process Clause when it obtains a conviction by presenting testimony the prosecuting authorities know was perjured. In one case, the Court stated in dictum that the clause

The Court has applied that principle to require state officials to controvert allegations that knowingly false testimony had been used to convict7 and to overturn convictions found to have been so procured.8 Extending the principle, the Court in Miller v. Pate overturned a conviction obtained after the prosecution had represented to the jury that a pair of men’s shorts found near the scene of a crime belonged to the defendant and that they were stained with blood; the defendant showed in a habeas corpus proceeding that no evidence connected him with the shorts, the shorts were not in fact bloodstained, and the prosecution had known those facts.9

This line of reasoning has also required disclosure to the defense of information that the prosecution did not rely on at trial.10 In Brady v. Maryland, the Court held that “the suppression by the prosecution of evidence favorable to an accused upon request violates due process where the evidence is material either to guilt or to punishment, irrespective of the good faith or bad faith of the prosecution.” 11 In that case, the prosecution had suppressed an extrajudicial confession of defendant’s accomplice that he had actually committed the murder.12 In a subsequent case, the Court described the “heart of the holding in Brady” as concerning

In United States v. Agurs, the Court summarized and expanded the prosecutor’s obligation to disclose exculpatory evidence to the defense, even in the absence of a request by the defendant, or upon a general request.14 The Agurs Court laid out three due process principles that apply to the use of evidence in criminal cases. First, if the prosecutor knew or should have known that testimony given during the trial was perjured, the conviction must be set aside if there is any reasonable likelihood that the false testimony could have affected the judgment of the jury.15 Second, as established in Brady, if the defense specifically requested certain evidence and the prosecutor withheld it, the conviction must be set aside if the suppressed evidence might have affected the outcome of the trial.16 Third, as the Court held for the first time in Agurs, if the defense did not make a request at all, or simply asked for “all Brady material” or for “anything exculpatory,” the prosecution has a duty to reveal to the defense obviously exculpatory evidence.17 Under the third prong, if the prosecutor did not reveal relevant information, reversal of a conviction may be required, but only if the undisclosed evidence creates a reasonable doubt as to the defendant’s guilt.18

Agurs left open questions about how courts should evaluate the materiality of undisclosed evidence. The Court addressed those questions in the 1985 case United States v. Bagley.19 In Bagley, the Court established a uniform test for materiality, holding that evidence is material if there is a reasonable probability that, had the evidence been disclosed to the defense, the outcome of the proceeding would have been different.20 That materiality standard, also found in contexts outside of Brady inquiries,21 applies not only to exculpatory material, but also to material that would be relevant to the impeachment of witnesses.22 Thus, in a case where inconsistent earlier statements by a witness to an abduction were not disclosed, the Court weighed the specific effect that impeachment of the witness would have had on establishing the required elements of the crime and the punishment, concluding that there was no reasonable probability that the jury would have reached a different result.23

The Supreme Court has also held that “Brady suppression occurs when the government fails to turn over even evidence that is ‘known only to police investigators and not to the prosecutor',” and that “'the individual prosecutor has a duty to learn of any favorable evidence known to others acting on the government’s behalf in the case, including the police.’” 24

Footnotes

1

See Amdt14.S1.5.5.5 Guilt Beyond a Reasonable Doubt.

2

Rock v. Arkansas, 483 U.S. 44 (1987).

3

Wardius v. Oregon, 412 U.S. 470 (1973).

4

Chambers v. Mississippi, 410 U.S. 284 (1973). See also Davis v. Alaska, 415 U.S. 308 (1974) (refusal to permit defendant to examine prosecution witness about his adjudication as juvenile delinquent and status on probation at time, in order to show possible bias, was due process violation, although general principle of protecting anonymity of juvenile offenders was valid); Crane v. Kentucky, 476 U.S. 683 (1986) (exclusion of testimony as to circumstances of a confession can deprive a defendant of a fair trial when the circumstances bear on the credibility as well as the voluntariness of the confession); Holmes v. South Carolina, 547 U.S. 319 (2006) (overturning rule that evidence of third-party guilt can be excluded if there is strong forensic evidence establishing defendant’s culpability). But see Montana v. Egelhoff, 518 U.S. 37 (1996) (state may bar defendant from introducing evidence of intoxication to prove lack of mens rea).

5

North v. Russell, 427 U.S. 328 (1976).

6

Mooney v. Holohan, 294 U.S. 103, 112 (1935).

7

Pyle v. Kansas, 317 U.S. 213 (1942); White v. Ragen, 324 U.S. 760 (1945). See also New York ex rel. Whitman v. Wilson, 318 U.S. 688 (1943); Ex parte Hawk, 321 U.S. 114 (1914). But see Hysler v. Florida, 315 U.S. 411 (1942); Lisenba v. California, 314 U.S. 219 (1941).

8

Napue v. Illinois, 360 U.S. 264 (1959); Alcorta v. Texas, 355 U.S. 28 (1957). In the former case, the principal prosecution witness was the defendant’s accomplice, and he testified that he had received no promise of consideration in return for his testimony. In fact, the prosecutor had promised him consideration, but did nothing to correct the false testimony. See also Giglio v. United States, 405 U.S. 150 (1972) (same). In the latter case, involving a husband’s killing of his wife because of her infidelity, a prosecution witness testified at the habeas corpus hearing that he told the prosecutor that he had been intimate with the woman but that the prosecutor had told him to volunteer nothing of it, so that at trial he had testified his relationship with the woman was wholly casual. In both cases, the Court deemed it irrelevant that the false testimony had gone only to the credibility of the witness rather than to the defendant’s guilt. Cf. Durley v. Mayo, 351 U.S. 277 (1956). But see Smith v. Phillips, 455 U.S. 209, 218–21 (1982) (prosecutor’s failure to disclose that one of the jurors has a job application pending before him, thus rendering him possibly partial, does not go to fairness of the trial and due process is not violated).

9

386 U.S. 1 (1967).

10

The Constitution does not require the government, prior to entering into a binding plea agreement with a criminal defendant, to disclose impeachment information relating to any informants or other witnesses against the defendant. United States v. Ruiz, 536 U.S. 622 (2002). Nor has it been settled whether inconsistent prosecutorial theories in separate cases can be the basis for a due process challenge. Bradshaw v. Stumpf, 545 U.S. 175 (2005) (Court remanded case to determine whether death sentence was based on defendant’s role as shooter because subsequent prosecution against an accomplice proceeded on the theory that, based on new evidence, the accomplice had done the shooting).

11

373 U.S. 83, 87 (1963). In Jencks v. United States, 353 U.S. 657 (1957), in the exercise of its supervisory power over the federal courts, the Court held that the defense was entitled to obtain, for impeachment purposes, statements that had been made to government agents by government witnesses during the investigatory stage. Cf. Scales v. United States, 367 U.S. 203, 257–58 (1961). A subsequent statute modified but largely codified the decision and was upheld by the Court. Palermo v. United States, 360 U.S. 343 (1959), sustaining 18 U.S.C. § 3500.

12

Although the state court in Brady had allowed a partial retrial so that the accomplice’s confession could be considered in the jury’s determination of whether to impose capital punishment, it had declined to order a retrial of the guilt phase of the trial. The Court rejected the defendant’s appeal of the latter decision. As the Court saw it, the issue was whether the state court could have excluded the defendant’s confessed participation in the crime on evidentiary grounds, as the defendant had confessed to facts sufficient to establish grounds for the crime charged.

13

Moore v. Illinois, 408 U.S. 786, 794–95 (1972) (finding Brady inapplicable because the evidence withheld was not material and not exculpatory). See also Wood v. Bartholomew, 516 U.S. 1 (1995) (per curiam) (holding no due process violation where prosecutor’s failure to disclose the result of a witness’ polygraph test would not have affected the outcome of the case). The Court has not extended Brady toward a general requirement of criminal discovery. See Giles v. Maryland, 386 U.S. 66 (1967). In Cone v. Bell, 556 U.S. 449, 472, 476 (2009), the Court emphasized the distinction between the materiality of the evidence with respect to guilt and the materiality of the evidence with respect to punishment, and concluded that, although the evidence that had been suppressed was not material to the defendant’s conviction, the lower courts had erred in failing to assess its effect with respect to the defendant’s capital sentence.

14

427 U.S. 97 (1976).

15

427 U.S. at 103–04; cf. Mooney v. Holohan, 294 U.S. 103 (1935).

16

427 U.S. at 104–06; cf. Brady v. Maryland, 373 U.S. 83 (1963). A statement by the prosecution that it will “open its files” to the defendant appears to relieve the defendant of his obligation to request such materials. See Strickler v. Greene, 527 U.S. 263, 283–84 (1999); Banks v. Dretke, 540 U.S. 668, 693 (2004).

17

427 U.S. at 106–07.

18

427 U.S. at 106–14. This was the Agurs fact situation. There is no obligation that law enforcement officials preserve breath samples that have been used in a breath-analysis test; to meet the Agurs materiality standard, “evidence must both possess an exculpatory value that was apparent before the evidence was destroyed, and be of such a nature that the defendant would be unable to obtain comparable evidence by other reasonably available means.” California v. Trombetta, 467 U.S. 479, 489 (1984). See also Arizona v. Youngblood, 488 U.S. 51 (1988) (negligent failure to refrigerate and otherwise preserve potentially exculpatory physical evidence from sexual assault kit does not violate a defendant’s due process rights absent bad faith on the part of the police); Illinois v. Fisher, 540 U.S. 544 (2004) (per curiam) (the routine destruction of a bag of cocaine eleven years after an arrest, the defendant having fled prosecution during the intervening years, does not violate due process).

19

473 U.S. 667 (1985).

20

473 U.S. at 682. Put differently, a Brady violation requires a showing that the favorable evidence could reasonably be taken to put the whole case in such a different light as to undermine confidence in the verdict. Kyles v. Whitley, 514 U.S. 419, 435 (1995). Accord Smith v. Cain, 565 U.S. 73 (2012) (prior inconsistent statements of sole eyewitness withheld from defendant; state lacked other evidence sufficient to sustain confidence in the verdict independently).

21

See United States v. Malenzuela-Bernal, 458 U.S. 858 (1982) (testimony made unavailable by Government deportation of witnesses); Strickland v. Washington, 466 U.S. 668 (1984) (incompetence of counsel).

22

473 U.S. at 676–77. See also Wearry v. Cain, 136 S. Ct. 1002, 1007 (2016) (per curiam) (finding that a state post-conviction court had improperly (1) evaluated the materiality of each piece of evidence in isolation, rather than cumulatively; (2) emphasized reasons jurors might disregard the new evidence, while ignoring reasons why they might not; and (3) failed to consider the statements of two impeaching witnesses).

23

Strickler v. Greene, 527 U.S. 263, 296 (1999); see also Turner v. United States, 137 S. Ct. 1885, 1894 (2017) (holding that, when considering the withheld evidence in the context of the entire record, the evidence was “too little, too weak, or too distant” from the central evidentiary issues in the case to meet Brady's standards for materiality).

24

Youngblood v. West Virginia, 547 U.S. 867, 869–70 (2006) (per curiam) (quoting Kyles v. Whitley, 514 U.S. 419, 438, 437 (1995)).