The whole point behind the insanity defense is this, we do NOT put people in jail for being ill. For instance, if I had the measles and gave it to my wife and she died, am I guilty of murder, no because I was sick.
Courts applied the reasoning, if the person wasn’t ill, in this case mentally ill, would that person have committed the crime. In Yate’s case the jury said “No, if she had been well she wouldn’t have committed the murders.”
This worked very well till the 70s when people and pyschiatry in particular came around to the fact that all murders were by nature of comitting the act not well. This of course is wrong. John Hinkely brought a final uproar to the insanity defense.
Even though very, very few people ever got “away” with the defense, most places adopted the “guilty but mentally ill.” This makes no sense, if you were really mentally ill you would have no control over your crime. But it’s what we live with.
As for the fairness, is anything in our system of justice fair. Does anyone believe for one second OJ Simpson would’ve been found not guilty if he hadn’t been able to afford high price attorneys? (Whether or not he did it?) Why is it that if John a rich guy and Jack a poor guy each murder someone and the judge sets their bail at 1 million dollars. Because John is rich he goes free, till his trail, while Jack for NO other reason than being poor must stay in jail till his trial, and God knows what could happen in there.
Why is it that women rarely ever get the death penalty? Does anyone think if Susan Smith’s husband had killed the kids he’d NOT be sitting on death row. She isn’t. But he probably would be for the same crime.