## Facts

- Federal prosecutors charged a multi-defendant cocaine and crack-cocaine distribution conspiracy and related substantive drug offenses in the Southern District of Indiana.
- Four defendants (Gordon Thornton, Garrick Jackson, Kirk Reynolds, and Michael Harris) proceeded to trial; nine others entered plea deals and testified for the government.
- The government introduced cooperating witnesses’ proffer letters and written plea agreements, which conditioned potential sentencing benefits on providing truthful information and testimony.
- The district court admitted the cooperation documents into evidence and permitted the government to question cooperating witnesses about their agreements.
- The court instructed the jury that it alone determined witness credibility, that no inference of guilt could be drawn from others’ guilty pleas, and that cooperating-witness testimony should receive whatever weight the jury deemed appropriate.
- The jury convicted the four defendants, who appealed evidentiary rulings, including the admission and use of cooperation documents and certain documentary exhibits.

## Issues

1. Whether admitting cooperating witnesses’ plea agreements and proffer letters containing “truthful testimony” provisions, and allowing the government to emphasize those provisions, improperly bolstered witness credibility and required reversal.
2. Whether challenged evidentiary rulings on documentary exhibits violated the Federal Rules of Evidence, including authentication requirements.
3. Whether the combined use of cooperation agreements and trial instructions deprived defendants of a fair trial by implying official endorsement of government witnesses.

## Decision

- The Seventh Circuit affirmed the convictions.
- The court held that admission of plea agreements and proffer letters, including their truthfulness provisions, was not reversible error when used to show witness motive and bias and when accompanied by appropriate limiting instructions.
- The court found no improper prosecutorial vouching because the government did not claim personal belief in witness veracity or suggest extra-record means to verify truthfulness.
- The court upheld authentication determinations for certain routine documents based on distinctive characteristics and surrounding circumstances.

## Legal Principles

- Cooperation agreements and related proffer materials may be admitted to show a witness’s incentives, bias, and relationship with the government, and to permit meaningful cross-examination about those incentives.
- References in cooperation documents to an obligation to testify truthfully do not, without more, constitute impermissible vouching; vouching involves personal assurances of credibility or implied governmental verification beyond the record.
- Cautionary instructions that the jury alone judges credibility and that no inference may be drawn from others’ guilty pleas reduce any risk that cooperation agreements will be treated as guarantees of truth.
- Under Federal Rule of Evidence 901(b), documents may be authenticated through distinctive characteristics (such as names, addresses, and contextual fit) together with the circumstances of their discovery and use.

## Conclusion

The Seventh Circuit sustained the defendants’ drug-trafficking convictions, ruling that the government’s introduction and examination of cooperating witnesses using plea and proffer agreements containing truthfulness conditions was permissible absent vouching and in light of limiting instructions, and that routine documents could be authenticated through distinctive characteristics and context.


United States v. Thornton, 197 F.3d 241 (7th Cir. 1999)