Generally because they did something defining to make them not worthy of being treated like a human. They have to re-earn that right and if they do they can be released I don't care. But it's not something you just freely give after they did something to make you put them in there to begin with. Not saying people aren't able to be rehabilitated or anything of that nature; I believe in redemption as much as the next guy. But if you are in jail you deserve to be there. This guy needs proper care, however.
And my comment was more a less on the play of "He's crazy" rather than the actual room and straitjacket, just a bit of clarification
I was going to say, "Hard to re-earn such a right in solitary confinement!" but since you actually clarified that you did not literally mean that, then I think we actually do agree on the point.
My point is not that they be treated with respect and as good human beings, but that they still be treated like human beings -- that is, punished to jail, but not without the chance of mental treatment and without a chance to actually grow (books in prisons and work can be done and all). After that, if they are still dangerous for the rest of their life, I have no problem saying let them die there and rot there, really. I just mean that we should not forget that just because someone does something horrible, it does not give us the ethical right to act inhumane (read, torture, and read, keeping people locked in abysmal conditions). I know a lot of people do wish for things like this, though, for criminals to get it back a hundredfold and to spit on what's left of them with a good, "Served you right".
But even if it did serve them right, I don't think we, as human beings, should become so cruel and inhumane as to carry out such a sentence.
That's pretty much that.
I really agree with locking the guy up as long as it takes, forever if need be. I really don't like it when criminals get released and to know that the people they harmed sit in fear.