Yes, if they did whatever they did because they are insane. If they were delusional and believed in some weirs and insane world where they had to fight some evil that doesn't exist in reality, if they had hallucinations like voices in their head telling them to do whatever they did... In that case they need to be locked up in a psychic hospital and kept there until they are either healed and no longer dangerous or until they die of old age.
If they did whatever they did not because they are insane but in spite of their insanity - if they were able to see that what they did was wrong and a crime and still did it out of other motives, maybe such as greed or personal revenge - they should be going to prison.
I think you are aiming at Anders Beren Breivik, the man who killed 70 people in Oslo because he believed he had to "save the Norwegian race" from "islamic Invasion" or something. I don't know about him. He seemed much to smart and much to planned for a truly insane person. But I'd leave it to the doctors and the judges to decide that. I'm glad I don't have to judge that.
It depends on the circumstances. If the person truly does have mental issues and was suffering from some kind of insanity at the time then sure, they do belong in a psychiatric hospital.
If they are being put in any hospital, however, I do think that there should be one that is within the prison for them. If they murdered, regardless of why, they should not be out in public where they may do it again. Insanity does not dismiss the fact that they killed someone, and being treated does not ensure they will not do it again. They are still a threat, regardless why of they did do it.
There are mental hospitals for dangerous madmen (and madwomen) that are basically prisons with psychiatric personnel. Male bodybuilder nurses and psychiatrist doctors instead of prison guards. Locked doors. No exit. No civilized country will actually set a dangerous person free. Whoever is a menace to society but not able to control his or her own behavior belongs into such a hospital - where his insanity may or may not be cured - and not into a prison, along with normal, criminal inmates.
"Two kinds of crazy, those who murder people, and those who roll their $hit into tiny little balls." -Larry the Cable Guy . . . Anyways, Insanity cannot mean the state of mind the murderer had at the scene of the crime, that is BS. there has to be a history of mental illness, and it has to be the kind of mental illness which could be proved to lead to murder, or manslaughter.
no because if they are insane what will stop them for doing it again or learning there lesson. maybe a shorter time in jail, or at very least rehab
weirs ==> weird