California case of People v. Reed 53 Cal. App. 4th 389 , 61 Cal.Rptr. 2d 658 , where a Court of Appeals said that when, "a person commits an act based on a mistake of fact, his guilt or innocence is determined as if the facts were as he perceived them." See also Model Penal Code (MPC) § 5.01 states in relevant part that, "[a] person is guilty of an attempt to commit a crime if, acting with the kind of culpability otherwise required for commission of the crime, he . . . purposely engages in conduct which would constitute the crime if the attendant circumstances were as he believes them to be."

[Contributed by one of my students]