United States v. Yazzie
United States Court of Appeals for the Ninth Circuit
976 F.2d 1252 (9th Cir. 1992)
Johnny Yazzie (defendant), charged with statutory rape of a 15-and-a-half-year-old victim, defended himself on the ground he reasonably believed she was 16 on the night in question, and sought to introduce witness testimony about the victim's appearance -- her smoking, driving, makeup, and physical development -- as well as those witnesses' opinions that she appeared to be 16 years old. The district court permitted the descriptive testimony about her appearance but excluded the witnesses' actual opinions about her age; Yazzie was convicted and appealed.
Whether, under Federal Rule of Evidence 701, a lay witness may give opinion testimony if the testimony is rationally based on the witness's perception and is helpful to a clear understanding of the testimony or the determination of a fact at issue.