## Facts

- Don A. Elton, age 19, had sexual intercourse with a 14-year-old girl who was not his spouse.
- Under Utah Code Ann. § 76-5-401, unlawful sexual intercourse was a third-degree felony unless the actor was no more than three years older than the victim; Elton was more than three years older.
- Elton claimed the girl told him she was 18 and that he believed she was over 16; the girl claimed she told him she was 15.
- At trial, the court treated the offense as strict liability as to age, excluded evidence aimed at showing the reasonableness of Elton’s belief about age, and instructed the jury that mistake of age was no defense.
- Elton was convicted of third-degree felony unlawful sexual intercourse and appealed.

## Issues

1. Whether Utah Code Ann. § 76-5-401 makes unlawful sexual intercourse a strict-liability offense as to the victim’s age.
2. Whether Utah’s general mens rea provisions require the State to prove a culpable mental state regarding the victim’s age absent an express strict-liability directive.
3. Whether a defendant may present, and receive a jury instruction on, a reasonable mistake-of-age defense to felony unlawful sexual intercourse.

## Decision

- The Utah Supreme Court vacated its prior opinion on rehearing, reversed the conviction, and remanded for a new trial.
- The court held § 76-5-401 is not strict liability as to the victim’s age; the State must prove a culpable mental state regarding age (at least criminal negligence).
- The court held a reasonable mistake of fact as to the victim’s age is a valid defense to the felony charge.
- The trial court committed reversible error by excluding evidence of the basis and reasonableness of Elton’s belief and by instructing the jury that mistake of age was no defense.

## Legal Principles

- Under Utah’s criminal code, a culpable mental state is presumed required for each material element of an offense unless the legislature expressly imposes strict liability.
- Statutory silence on mens rea does not, by itself, establish legislative intent to impose strict criminal liability.
- For unlawful sexual intercourse under § 76-5-401, the victim’s age is a material element for which the prosecution must prove a culpable mental state (at least criminal negligence).
- A reasonable mistake of fact regarding the victim’s age can negate the required mental state and must be submitted to the jury when supported by evidence.
- Recognition of a mistake-of-age defense to felony unlawful sexual intercourse does not preclude liability for other offenses arising from the same conduct.

## Conclusion

The Utah Supreme Court set aside Elton’s conviction because § 76-5-401 requires proof of a culpable mental state as to the victim’s age and permits a reasonable mistake-of-age defense; the trial court therefore erred in excluding supporting evidence and instructing the jury that age mistake was no defense.


State v. Elton, 680 P.2d 727 (Utah 1984)