Kilen Patrick Dysthe, Appellant (defendant) v. the State of Wyoming, Appellee (plaintiff)

Summary

The Wyoming Supreme Court reversed Dysthe’s conviction for delivery of cocaine and remanded for a new trial. It held that the trial court abused its discretion by excluding defense witnesses relevant to impeaching the State’s principal witness and by restricting cross-examination concerning the foundation for another witness’s drug-identification opinion; the prosecutor also committed plain error by vouching for the State’s witnesses. The court concluded these errors were not harmless because the State’s case depended entirely on witness credibility.