We tried the state's mental hygiene commitment procedure. Basically you can swear out a warrant on someone and they will take him to the state mental hospital for an examination to determine if he should be hospitalized. Unfortunately something went wrong and they couldn't find him before the warrant expired.
I think Japan has a good model for handling gun control. Their murder rate is something like 5% compared to the USA. I've always said that I would give up my gun if everyone else gave up theirs. However that will never happen here in the USA.