Prosecutor disclosure, the reasonable-doubt standard, harmless error, and race-based jury strikes

Black-letter propositions

1. 01

   Suppression by the prosecution of evidence favorable to an accused who has requested it 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 (Brady v. Maryland).

2. 02

   The prosecution's duty to present all material evidence to the jury includes evidence bearing on a key witness's credibility, such as a promise of leniency in return for testimony, and it is not excused because the trial prosecutor did not know of the promise (Giglio v. United States).

3. 03

   A prosecutor does not violate the constitutional duty of disclosure unless the omission is sufficiently significant to result in the denial of the defendant's right to a fair trial, and the Constitution does not demand discovery of everything that might influence a jury (United States v. Agurs).

4. 04

   Proof beyond a reasonable doubt, required by the Due Process Clause in criminal trials, is among the essentials of due process and fair treatment required during the adjudicatory stage when a juvenile is charged with an act that would be a crime if committed by an adult (In re Winship).

5. 05

   Before a constitutional error can be held harmless, the court must be able to declare its belief that it was harmless beyond a reasonable doubt, and the state bears the burden of showing this (Chapman v. California).

6. 06

   A prosecutor's comment on the defendant's failure to testify, and a jury instruction allowing an adverse inference from it, violate the Fifth Amendment, and the state must show that this error did not contribute to the conviction.

7. 07

   The Equal Protection Clause forbids a prosecutor from using peremptory challenges to exclude jurors on account of race (Batson v. Kentucky).

8. 08

   A defendant makes a prima facie case of purposeful discrimination in jury selection by showing that he is a member of a cognizable racial group and that the prosecutor exercised peremptory challenges to remove members of that group from the jury, and that these facts and other relevant circumstances raise an inference of discrimination.

9. 09

   Once the defendant makes a prima facie showing, the burden shifts to the state to come forward with a neutral explanation for challenging the jurors.

10. 10

    The prosecutor may not rebut a prima facie showing by stating that he challenged the jurors on the assumption that they would be partial to the defendant because of their shared race, or by affirming his good faith in individual selections.

11. 11

    A defendant may establish a prima facie case of purposeful discrimination solely on evidence concerning the prosecutor's exercise of peremptory challenges at the defendant's own trial.

12. 12

    Batson does not require the defendant to show that the prosecutor engaged in a pattern of race-based strikes across multiple prior cases.

Use this attack sequence under time

Common wrong turns

• Good faith or bad faith of the prosecutor does not decide whether suppression of material favorable evidence violates due process.
• The burden of showing that constitutional error was harmless is on the state, and the standard is beyond a reasonable doubt.
• A prosecutor cannot rebut a Batson showing by asserting that he acted in good faith or by relying on race-based assumptions.

Worked example

A prosecutor promises a key witness a reduced sentence in exchange for testimony, and the trial prosecutor, unaware of it, tells the jury there were no deals. The defendant learns of the promise after conviction.

Practice this topic

Disclosure of favorable evidence

In Brady v. Maryland, 373 U.S. 83 (1963), the Supreme Court held that suppression by the prosecution of evidence favorable to an accused who has requested it 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. In Giglio v. United States, 405 U.S. 150 (1972), the Court held that the prosecution's duty to present all material evidence to the jury was not fulfilled when it did not disclose an alleged promise of leniency to its key witness, and that neither the assistant's lack of authority nor his failure to inform his superiors was controlling.

In United States v. Agurs, 427 U.S. 97 (1976), the Court held that a prosecutor does not violate the constitutional duty of disclosure unless the omission is sufficiently significant to result in the denial of the defendant's right to a fair trial, and that the Constitution does not demand discovery of everything that might influence a jury.

Burden of proof and harmless error

In In re Winship, 397 U.S. 358 (1970), the Court held that proof beyond a reasonable doubt, which the Due Process Clause requires in criminal trials, is among the essentials of due process and fair treatment required in the adjudicatory stage of a juvenile delinquency proceeding in which the juvenile is charged with an act that would be a crime if committed by an adult.

In Chapman v. California, 386 U.S. 18 (1967), the Court held that before a constitutional error can be held harmless the court must be able to declare its belief that it was harmless beyond a reasonable doubt, and it found that the state had not shown this where the prosecutor repeatedly commented on the defendants' failure to testify and the judge instructed the jury on the inference.

Race-based peremptory challenges

Batson v. Kentucky, 476 U.S. 79 (1986), held that the Equal Protection Clause forbids a prosecutor from challenging jurors solely on account of race, and that a defendant may establish a prima facie case of purposeful discrimination solely on evidence concerning the prosecutor's exercise of peremptory challenges at the defendant's own trial. The defendant must show membership in a cognizable racial group and that the prosecutor removed members of that group, and the relevant circumstances must raise an inference of discrimination.

Once the prima facie showing is made, the burden shifts to the state to come forward with a neutral explanation for challenging the jurors, and the prosecutor may not rebut the showing by saying he assumed the jurors would be partial to the defendant because of their shared race or by affirming his good faith in individual selections.

Frequently asked questions