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Defendants' Rights to Exculpatory Evidence: Brady v. Maryland

Defendants’ Rights to Exculpatory Evidence: Brady v. Maryland

It is a feature of our criminal justice system that each defendant must receive a fair trial. For that to happen, the defendant’s attorney must have access to evidence that tends to demonstrate his client’s innocence.

To ensure access to this evidence, called exculpatory evidence, the United States Supreme Court has ruled that prosecutors must disclose “exculpatory” evidence, which means evidence that tends to demonstrate innocence. This rule was announced in the 1963 case, Brady v. Maryland.[1]

            In that case, John Brady and his companion Charles Boblit were accused of robbing and killing another man. They were arrested, tried separately, and each convicted of murder. To avoid the death penalty, Brady took the stand and admitted to participating in the crime, but claimed that Boblit killed the victim. To support his client’s claim, Brady’s defense attorney sought to examine all statements that Boblit made to the prosecutor. Although the prosecutor gave the defense attorney access to these statements, he did not provide him with the one statement, dated July 9, 1958, in which Boblit admitted to having committed the murder.[2]

To that point, a defendant’s rights were only considered violated when a prosecutor behaved in bad faith by intentionally concealing exculpatory evidence or intentionally allowing false testimony at trial. The Court’s decision in Brady altered the criminal procedure landscape. Although the state prosecutor did not conceal the statement of Boblit out of trickery or intent to deceive, the Court reasoned that any concealment of exculpatory evidence violated Brady’s right to a fair trial and established the rule that prosecutors must turn over, upon request, all favorable evidence that “materially” relates to a defendant’s guilt or appropriate punishment.[3]

Other Examples

            The Supreme Court in Brady did not define “material” or offer guidance on how a defense attorney’s request for exculpatory evidence should be worded. Later decisions have attempted to clear up any confusion.

In Giglio v. United States, the prosecution’s primary witness provided nearly all the evidence that established the defendant’s guilt. However, the prosecution did not disclose the fact that his testimony was obtained in exchange for an offer of leniency. The Supreme Court determined that this leniency offer was “material” and withholding that information from the jury and from defense counsel violated the defendant’s right to a fair trial. The case established that evidence is “materially” exculpatory if it would have reasonably affected the judgment of the jury. Here, the evidence of the leniency offer could have affected the jury’s conclusion because it could have cast into doubt the witness’ credibility.[4] The Court further ruled that it did not matter whether the prosecution intentionally withheld this evidence. Even if it were withheld negligently without bad faith, it still violated the defendant’s due process rights. The defendant was therefore entitled to a new trial.

“Material” has been subsequently defined as “a reasonable probability that if the evidence had been disclosed to the defense, the outcome of the trial would have been different.” The “reasonable probability” language must be sufficient to undermine the confidence in the outcome of the case.

In United States v. Bagley, the government charged a defendant with firearm and narcotics offenses and the defendant was eventually convicted of the narcotics offenses. The prosecution did not disclose that the primary witness in the firearm prosecution was a paid informant. This fact, however, was not considered material to the narcotics offense conviction. The Court reasoned that there was not a reasonable probability that the outcome of the case would have been different because the informant was only compensated for testimony relating to the firearm offense, which the defendant was acquitted of in any case.[5]

The Brady case itself did not set out how a defense attorney’s request for materially exculpatory evidence should be worded. Now, however, the Supreme Court has made clear that prosecutors must turn over all materially exculpatory evidence in all circumstances, even when defendants do not ask for the evidence.[6]

How Prosecutors Satisfy Brady and What Happens if They Don’t

            Some prosecuting agencies issue guidelines on what evidence prosecutors must disclose and how they should disclose it.[7] Other prosecuting agencies have adopted “open file” policies, where a defendant can access a prosecutor’s entire case file.[8]

            There are several possible consequences if a prosecutor does not comply with her obligations under Brady. A court can order a new trial if the failure to disclose the information could have made a difference in the initial trial. Second, the prosecutor may face disciplinary actions for violating the responsibility to disclose exculpatory evidence. For example, former Durham County District Attorney Mike Nifong was disbarred, in part, for failing to disclose exculpatory evidence in a high-profile Duke University lacrosse case.[9]

Finally, if a court finds a pattern of Brady violations in a district attorney’s office, a prosecuting attorney could be subjected to civil rights lawsuits.[10]

Brady v. Maryland is a landmark criminal procedure case that rivals Miranda v. Arizona in importance. It seeks to ensure that criminal defendants enjoy fair opportunities to defend themselves by providing them access to information that tends to show their innocence.


[1] 373 U.S. 83, 83 S. Ct. 1194, 10 L.Ed.2d 215 (1963)

[2] Id.

[3] Id.

[4] Giglio v. United States, 405 U.S. 150, 92 S. Ct. 763, 31 L.Ed.2d 104 (1972)

[5] United States v. Bagley, 473 U.S. 667, 105 S. Ct. 3375, 87 L.Ed.2d 481 (1985)

[6] United States v. Agurs, 427 U.S. 97, 96 S. Ct. 2392, 49 L.Ed.2d 342 (1976)

[7] https://www.justice.gov/archives/dag/memorandum-department-prosecutors

[8] Strickler v. Greene, 527 U.S. 263, 283 n.23, 119 S. Ct. 1936, 1949, 144 L.Ed.2d 286, 303 (1999)

[10] Dahlia Lithwick, “Clarence Thomas writes one of the meanest Supreme Court decisions ever,” retrieved from http://www.slate.com/articles/news_and_politics/jurisprudence/2011/04/cruel_but_not_unusual.html