These sorts of cases tend to bring out a lot of emotions and information goes flying!

It’s fairly hard to succeed with an insanity defense. The burden of proof may vary by state (I don’t know whether it does off the top of my head) but I believe at least federally the defendant must prove by a preponderance of the evidence that they either didn’t understand what they were doing at the time they were doing it, or understood what they were doing but not that it was wrong. That’s an overall hard thing to do because you’re arguing state of mind at an exact period of time.

Even when they do succeed and are hospitalized, they don’t ever just get to leave the hospital. They’re subject to competency review hearings and only those determine there fitness for release. And then we have people like Andrea Yates who decline the hearings and simply choose to remain hospitalized.