Giglio v. United States

Giglio v. United States
Argued October 12, 1971
Decided February 24, 1972
Full case nameJohn Giglio v. United States
Citations405 U.S. 150 (more)
92 S. Ct. 763; 31 L. Ed. 2d 104; 1972 U.S. LEXIS 83
Case history
PriorCertiorari to the United States Court of Appeals for the Second Circuit
Holding
Prosecution's failure to inform the jury that a witness had been promised not to be prosecuted in exchange for his testimony was a failure to fulfill the duty to present all material evidence to the jury, and constituted a violation of due process, requiring a new trial.
Court membership
Chief Justice
Warren E. Burger
Associate Justices
William O. Douglas · William J. Brennan Jr.
Potter Stewart · Byron White
Thurgood Marshall · Harry Blackmun
Lewis F. Powell Jr. · William Rehnquist
Case opinion
MajorityBurger, joined by unanimous
Justices Powell and Rehnquist took no part in the consideration or decision of the case.
Laws applied
U.S. Const. amend. V

Giglio v. United States, 405 U.S. 150 (1972), is a United States Supreme Court case in which the Court held that the prosecution's failure to inform the jury that a witness had been promised not to be prosecuted in exchange for his testimony was a failure to fulfill the duty to present all material evidence to the jury, and constituted a violation of due process, requiring a new trial. This is the case even if the failure to disclose was a matter of negligence and not intent. The case extended the Court's holding in Brady v. Maryland, requiring such agreements to be disclosed to defense counsel. As a result of this case, the term Giglio material is sometimes used to refer to any information pertaining to deals that witnesses in a criminal case may have entered into with the government.