I'm no expert by any means, but I understand that "insanity" is a legal term used in determining a person's culpability or lack thereof, and not a clinical/medical diagnosis at all. There's a disconnect between the actual field of mental health, and the judicial system which lags way, way behind and is pretty clueless about things like this and therefore hangs onto broad simplistic antiquated notions that fit its legalistic framework.
Kor
Essentially correct.
Insanity is a legal concept regarding a person's ability to discern right from wrong at the time of a crime, or understanding the nature of their criminal act at the time of commission. It is not a term used in mental health.