## Facts

- Johnny Yazzie, Jr., a Navajo tribal member, was prosecuted in federal court for conduct occurring on the Navajo reservation on July 19, 1989.
- The charges included aggravated sexual abuse (forcible rape) and sexual abuse of a minor (statutory rape) under federal statutes applicable in Indian country.
- The victim was 15½ years old at the time; Yazzie admitted sexual intercourse occurred.
- The jury acquitted Yazzie of aggravated sexual abuse but convicted him of sexual abuse of a minor.
- Yazzie’s sole defense to the statutory count was the affirmative defense that he reasonably believed the victim was at least sixteen.
- Yazzie testified that he believed the victim was at least sixteen based on her appearance and conduct (including smoking, driving, use of makeup, and physical maturity), and that she never told him her age.
- Yazzie offered multiple lay witnesses who had observed the victim and would have testified that she appeared to be at least sixteen (or within an older age range).
- The district court permitted witnesses to describe the victim’s appearance and behavior but excluded their lay opinions about her apparent age.

## Issues

1. Whether Federal Rule of Evidence 701 required admission of lay witness opinions about the victim’s apparent age when offered to support a defendant’s affirmative defense of reasonable mistake of age.
2. Whether exclusion of that lay opinion testimony was harmless given that the reasonableness of Yazzie’s belief was the central disputed issue on the statutory-rape count.

## Decision

- The Ninth Circuit reversed the conviction for sexual abuse of a minor and remanded.
- The court held the district court erred by excluding lay opinion testimony that the victim appeared to be at least sixteen.
- The court found the error was not harmless because the excluded opinions bore directly on the only contested question relevant to the affirmative defense.

## Legal Principles

- Under Federal Rule of Evidence 701, lay opinion testimony is admissible when it is rationally based on the witness’s perception, helpful to determining a fact in issue, and not based on specialized knowledge.
- A lay witness’s estimate of a person’s apparent age, grounded in personal observation, is a permissible lay opinion rather than expert testimony.
- Testimony about apparent age is a factual opinion and is distinct from an impermissible legal conclusion about whether a statutory defense is satisfied.
- Excluding admissible evidence is reversible error when it affects substantial rights, particularly where the evidence is central to the defendant’s only defense.

## Conclusion

The court concluded that lay opinions regarding the victim’s apparent age were admissible under Rule 701 and directly relevant to the defendant’s reasonable-mistake-of-age defense; because the district court’s exclusion of that corroborating evidence was prejudicial, the conviction was reversed and the case remanded.


United States v. Yazzie, 976 F.2d 1252 (9th Cir. 1992)