“ ‘Ignorantia facti excusat,’ however, is obviously too sweeping even for a general statement of law, because it is clear (to mention only one point for the moment) that if a certain deed would constitute exactly the same crime under either of two factual situations, it will be no excuse that one was mistaken for the other.” Rollin M. Perkins & Ronald N. Boyce, Criminal Law 1044 (3d ed. 1982).
ignorantia facti excusat
ignorantia facti excusat (ig-n[schwa]-ran-shee-[schwa] fak-tI ek-skyoo-sat or -zat). [Latin] Ignorance of fact is an excuse; whatever is done under a mistaken impression of a material fact is excused or provides grounds for relief. • This maxim refers to the principle that acts done and contracts made under mistake or ignorance of a material fact are voidable. [Cases: Criminal Law 33. C.J.S. Criminal Law § 93.]