I'm a forensic psychiatrist. If there were an easy answer to this, we would have found it already, but I'll offer the following observation:

I currently work in Oregon, where (in practice) it's more difficult than any other state or country where I have worked to admit someone involuntarily to the hospital. This has resulted in a greater number of mentally ill people staying untreated until the point that they do something that gets them arrested (which may or may not involve serious harm to someone else).

In my opinion, this particular balance between individual autonomy vs involuntary treatment does not seem to be a net positive for either the community or individual rights.