Oh looky who showed up when there's one data point out of a million that supports his ridiculous narrative.
I can solve your so-called conundrum of what to do with "them," though: absolutely nothing. You don't do anything with them. What you do is BAN THE FUCKING GUNS, and then it doesn't matter that the streets are crawling with depressed, mentally unstable people. Depressed, mentally unstable people will always be with us - that's something we actually CAN'T do something about. Guns, on the other hand, are something we CAN do something about.
Problem. Solved.
One data point? Are you referring to the person being trans? I don’t think that is much of a factor. The much bigger issue is what do you do when someone has major mental issues? Even if somehow we were to remove all guns they could still inflict damage in plenty of other ways. And if you’re unfortunate enough to have someone like that in your family are you responsible for them financially and their actions? No one wants to have a family member like that but obviously some people do.