A narrowly divided California Supreme Court on Monday rejected a delusional belief in a need for self-defense as a device to reduce a murder charge to manslaughter in People v. Elmore, S188238:

A killing committed because of an unreasonable belief in the need for self-defense is voluntary manslaughter, not murder. "Unreasonable self-defense, also called imperfect self-defense, 'obviates malice because that most culpable of mental states "cannot coexist" with an actual belief that the lethal act was necessary to avoid one's own death or serious injury at the victim's hand.' (People v. Rios (2000) 23 Cal.4th 450, 461.)" (People v. Beltran (2013) 56 Cal.4th 935, 951.)

The question here is whether the doctrine of unreasonable self-defense is available when belief in the need to defend oneself is entirely delusional. We conclude it is not. No state, it appears, recognizes "delusional self-defense" as a theory of manslaughter. We have noted that unreasonable self-defense involves a mistake of fact. (In re Christian S. (1994) 7 Cal.4th 768, 779, fn. 3 (Christian S.).) A purely delusional belief in the need to act in self-defense may be raised as a defense, but that defense is insanity.

For what it's worth, CJLF submitted one of its rare briefs in support of a defendant in Christian S.