7th circuit court of appeals decision
Prosecutorial Misconduct – Knowing Use of False Testimony
When the government obtains a conviction through the knowing use of false testimony, it violates a defendant’s due process rights. Napue v. Illinois, 360 U.S. 264, 269 (1959); United States v. Bagley, 473 U.S. 667, 679 n.8 (1984) (discussing the evolution of the rule in Napue). To obtain a new trial, the defendant must establish: (1) that there was false testimony; (2) that the government knew or should have known it was false; and (3) that there is a likelihood that the false testimony affected the judgment of the jury. United States v. Saadeh, 61 F.3d 510, 523 (7th Cir.1995).
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The government’s argument is misplaced. For one, Williams’s false testimony was conclusively established. But even if weren’t, none of those cases limits a defendant’s due process rights to situations where it can be conclusively established that the government witness was lying. In fact, we have held the opposite. In Boyd, we noted that Napue does not require that the witness could be successfully prosecuted for perjury. United States v. Boyd, 55 F.3d 239, 243 (7th Cir. 1995). In this area of the law, the governing principle is simply that the prosecutor may not knowingly use false testimony. This includes “half-truths” and vague statements that could be true in a limited, literal sense but give a false impression to the jury. Id. (“It is enough that the jury was likely to understand the witness to have said something that was, as the prosecution knew, false.”). To uphold the granting of a new trial, there does not need to be conclusive proof that the testimony was false or that the witness could have been prosecuted for perjury; all that matters is that the district court finds that the government has knowingly used false testimony. Thus, we reject the government’s argument that a claim under Napue can only be made when it can be established that the witness is lying.
Only a few Wisconsin cases have been decided under Napue (whether because of prosecutorial rectitude or deviousness can’t be known), and 7th Circuit holdings aren’t binding in state court, but the principles cited above are beyond dispute.