Opinion ID: 519281
Heading Depth: 2
Heading Rank: 4

Heading: New Evidence Concerning Credibility of Witnesses

Text: 26 The obligation under Brady to produce evidence material to a defendant's guilt or punishment includes production of impeachment evidence. Bagley v. Lumpkin, 798 F.2d 1297, 1300 (9th Cir.1986). Furthermore, exposure of a witness' motivation in testifying is a proper and important function of the constitutional right of cross-examination. Davis v. Alaska, 415 U.S. 308, 316-17, 94 S.Ct. 1105, 1110-11, 39 L.Ed.2d 347 (1974). 27 There exists a constitutional obligation on prosecutors to report to the defendant and to the court whenever government witnesses lie under oath. Trombetta, 467 U.S. at 485, 104 S.Ct. at 2532. Furthermore, when the reliability of a given witness may well be determinative of guilt or innocence, nondisclosure of evidence affecting credibility warrants a new trial irrespective of the good faith or bad faith of the prosecution. Giglio, 405 U.S. at 153-54, 92 S.Ct. at 765-66. But newly discovered evidence to impeach a government witness does not warrant a new trial when the evidence would not have affected the jury's assessment of the witness' credibility and when the witness was subjected to vigorous cross-examination. Steel, 759 F.2d at 714.