Well, I don't know. I've noticed people maybe getting a little annoyed with some of the posts I am posting here, or maybe I am just imagining things. (I think I will wait before posting something that isn't Star Trek-related, at least for a while.) But you know, social issues are important to me. And the US is the only country that I at least know of, that is considering eliminating the insanity defense in some locations. We're also the only country that puts actively psychotic people in prison. Now, you do have to put that in the right perspective. Because a person in a Russian mental hospital would probably wish he was in a relatively nice American prison. But at least in Russia, as well as everywhere else, they agree that sick people belong in hospitals.
Anyways, I am not trying to change anyone's minds on this. But I thought you'd at least find the following informative.
The M'Naghten rule was codified in the 1840s, in an English case involving Daniel M'Naghten. It states that "...that every man is to be presumed to be sane, and ... that to establish a defence on the ground of insanity, it must be clearly proved that, at the time of the committing of the act, the party accused was labouring under such a defect of reason, from disease of the mind, as not to know the nature and quality of the act he was doing; or if he did know it, that he did not know he was doing what was wrong...."
But the insanity defense is much older than that though. The “wild best test” transformed insanity law and first found use in the 1724 case of Rex v. Arnold. The trial judge (Judge Tracy) instructed the jurors to acquit the defendant by reason of insanity if it was found that he was “a man totally deprived of his understanding and memory, and doth not know what he is doing, no more than a brute, or a wild beast, such a one is never the object of punishment.” And the concept of defense by insanity has existed since ancient Greece and Rome. The first known recognition of insanity as a defense to criminal charges was recorded in a 1581 English legal treatise stating that, “If a madman or a natural fool, or a lunatic in the time of his lunacy” kills someone, they cannot be held accountable. The British courts came up with the “wild beast” test in the 18th Century, in which defendants were not to be convicted if they understood the crime no better than “an infant, a brute, or a wild beast.”
As any first year law student can tell you, the insanity defense comes up in less than one percent of the cases, and always has, because it is relatively rare.
BTW, "...the party accused was labouring under such a defect of reason, from disease of the mind, as not to know the nature and quality of the act he was doing..." means the party didn't know what he was even doing at all, like if he thought he was stabbing a log instead of a person. And "...or if he did know it, that he did not know he was doing what was wrong..." means he thought there was some other reason why he or she was doing it, like if someone killed their dentist, because he thought he was going to murder him, instead of clean his teeth.
The insanity defense is actually part of a much larger group of defenses, called affirmative defenses, including justification, duress, impossibility, and entrapment, just to name the ones I can remember. I am not a lawyer, so I can't imagine which one is used the most. But I would guess entrapment.
Just about every, if not every, other nation on earth has some variation of the insanity defense. So what's the big deal?