Re: They're not morons.
@Charles 9:"...or simply have BOTH at the same time."
That's the part that really worries me. A bad law would probably not do much to stop violent crime and would likely make the existing abuse problem worse.
It's possible that cleaning up the hold/commitment system would reduce violent crime even without any tightening of the background check system, since we're currently wasting a lot of beds and clinic resources holding people who pose no credible risk to anyone.
Shrinks like to go after harmless eccentrics for the same reason that police departments like to focus on speeding and non-violent drug dealing and prostitution - going after dangerous people is scary and labor intensive - so getting them back 'on task' might be as close to a panacea as we'll get on this one.