State v. Olsen
Citation: (Criminal Law — mens rea / mistake of fact context)
Facts
Olsen was charged with a crime requiring a mental state element. He raised a mistake-of-fact defense, arguing that his reasonable belief about the facts negated the required mens rea for the offense.
Issue
Does a reasonable mistake of fact negate the mens rea required for criminal liability?
Holding
A reasonable mistake of fact negates criminal liability where the offense requires a culpable mental state (purpose, knowledge, recklessness), provided the mistake is genuine and reasonable. Strict liability offenses admit no mistake-of-fact defense.
Rule
Mistake of fact: A genuine mistake of fact — even if unreasonable — can negate purpose or knowledge. A reasonable mistake of fact negates recklessness. Strict liability offenses (typically regulatory/public welfare offenses) have no mens rea element, so mistake of fact provides no defense.
Significance
- Illustrates the relationship between mistake of fact and the specific mens rea required
- Mistake must be sincere; reasonableness matters when recklessness is the standard
- Distinguished from mistake of law, which generally provides no defense