I don't know this guy's history, but getting kids help before they become adults would help them to turn into less mumped up adults. Again, not going to catch every crazy person when they are a kid but it would help reduce the overall number of crazy adults roaming the streets. For instance, Adam Lanza had known issues that were not properly addressed early in his life which lead to a downward spiral into a worsening state of mental health and isolation.
it doesn't just go away if you're actually crazy. like you get some treatment as a kid and now you're not a nut as an adult.
even the ones we can get committed are ultimately released because they improve with the strict supervision and forced medication. they get out because they have improved and the law requires it and then they stop complying with the medication and treatment and fall off the radar and then they reoffend and it starts all over again. that's a direct consequence of the law and their own pathology. that's the cycle.
the issue often isn't the treatment available it's how much are you willing to allow us to take away a crazy person's rights, their freedom and how low do you want that threshold to be when we can. unless you can force them eventually they (the truly crazy) become adults and they blow everyone the eff off. their doctors, their family, etc. that's a pretty dangerous line in the sand to shift.
platitudes like hey we should help them more are useless when the reality is that those that need it the most (paranoid, delusional nutjobs who might someday go on a killing spree) are the most fervently opposed to receiving it. more "help" isn't a legitimate answer. it's just crap people glibly pay lip service to at times like these.