## Facts

- Thomas D. Manske was tried in the Western District of Wisconsin for conspiracy to distribute cocaine under 21 U.S.C. § 846.
- The prosecution’s case depended primarily on cooperating witnesses Stephen Pszeniczka and Daniel Knutowski, who testified that Manske supplied them with cocaine from about 1993 to 1996 in repeated ounce-level deliveries.
- The cooperators described a regular meeting pattern (often weekly) and attributed approximately 5.78 kilograms of cocaine to Manske over the charged period.
- The government offered additional “tertiary” witnesses to corroborate portions of the cooperators’ account, but the case largely turned on the cooperators’ credibility.
- Manske denied supplying cocaine and contended the meetings involved illegal gambling rather than drug transactions.
- Before trial, Manske sought to impeach Pszeniczka by cross-examining him about alleged threats to other witnesses in related investigations, including threats to kill a witness unless he changed his statement and intimidation of other government witnesses.
- The government moved in limine to bar this line of impeachment; the district court granted the motion and excluded cross-examination of Pszeniczka about the alleged threats and related testimony from other threatened witnesses.
- A jury convicted Manske, and the district court sentenced him to 151 months’ imprisonment.

## Issues

1. Whether the district court abused its discretion under Federal Rule of Evidence 608(b) by categorically barring cross-examination about a cooperating witness’s alleged intimidation of other witnesses.
2. Whether the excluded intimidation evidence was probative of credibility (truthfulness and/or bias) such that limiting inquiry impermissibly restricted meaningful impeachment.
3. Whether the restriction on cross-examination was harmless given the government’s reliance on the cooperating witnesses.

## Decision

- The Seventh Circuit reversed the conviction and remanded for a new trial.
- The court held the district court abused its discretion by imposing a blanket prohibition on inquiry into the alleged threats.
- The court concluded the error was not harmless because the excluded impeachment bore directly on the credibility of a key witness and undermined confidence in the verdict.

## Legal Principles

- Under Federal Rule of Evidence 608(b), specific instances of conduct may be a proper subject of cross-examination when they are probative of a witness’s character for truthfulness or untruthfulness.
- Witness intimidation aimed at influencing testimony can be probative of credibility because it reflects a willingness to interfere with truthful factfinding and may also show self-interest or bias.
- Trial courts have discretion to limit impeachment under Rule 608(b), but categorical limits that prevent meaningful testing of a key witness’s credibility can constitute an abuse of discretion.
- When the prosecution’s case rests largely on cooperating witnesses, improper restrictions on impeachment are less likely to be harmless because credibility is central to the jury’s decision.

## Conclusion

The Seventh Circuit ordered a new trial because the district court’s blanket exclusion of cross-examination concerning a principal cooperating witness’s alleged threats improperly limited credibility impeachment, and the resulting evidentiary gap undermined confidence in the jury’s verdict.


United States v. Manske, 186 F.3d 770 (7th Cir. 1999)