Stephen Breyer

“ That is, the difference between the traditional insanity defense and Idaho's standard is that the latter permits the conviction of an individual who knew what he was doing, but had no capacity to understand that it was wrong.
To illustrate with a very much simplified example: Idaho law would distinguish the following two cases. Case One: The defendant, due to insanity, believes that the victim is a wolf. He shoots and kills the victim. Case Two: The defendant, due to insanity, believes that a wolf, a supernatural figure, has ordered him to kill the victim. ”

“ The American Psychiatric Association tells us that "severe mental illness can seriously impair a sufferer's ability rationally to appreciate the wrongfulness of conduct." Brief for American Psychiatric Association et al. ”