Mistake of Fact

One of the most confusingly worded defenses in all of Criminal Law is Mistake of Fact. I will start with simply posting the California Jury Instruction as a juror would receive it:

The defendant is not guilty of (the crime) if he did not have the intent or mental state required to commit the crime because he reasonably did not know a fact or reasonably and mistakenly believed a fact. If the defendant’s conduct would have been lawful under the facts as he reasonably believed them to be, he did not commit.

If you unknowingly act based on an honest mistake of fact, you are typically not considered guilty of a crime. For instance, imagine leaving your keys in your car, returning to the parking lot, and driving away in a vehicle with keys in the ignition, only to later realize it’s not your car but someone else’s who made the same mistake. In this scenario, you wouldn’t be committing Grand Theft, as the crucial intent to permanently deprive the owner of their vehicle is missing – you simply believed it was your car. This genuine belief would serve as a complete defense against the charge of Grand Theft. For further insights on the defense of mistake of fact, reach out to Ontario Criminal Defense lawyer Adam Jackson today for a complimentary consultation and case review at (909) 939-7126. Based in Ontario, CA.