People v. Crane
Illinois Supreme Court
585 N.E.2d 99 (1991)
After fatally striking Gahan with numchucks during a struggle he claimed was self-defense, Crane (defendant), believing Gahan was dead, poured gasoline on him and set him on fire, only later learning Gahan may have still been alive at that point; at trial, medical experts could not conclusively determine whether Gahan was alive before the burning, and one doctor testified a layperson could reasonably believe an unconscious, injured body like Gahan's was dead. The trial court refused Crane's requested mistake-of-fact instruction (giving only a self-defense instruction), he was convicted, and the appellate court reversed, prompting the state's appeal to the Illinois Supreme Court.
Whether, in Illinois, mistake of fact is a valid defense if the mistake negates the existence of the mental state required for the crime to be proved beyond a reasonable doubt.