Even if you get a system good enough to overcome the base rate problem, you'll only end up labeling a bunch of mostly harmless people. Think a about a hypothetical uber-villain that would want to recruit children or teenagers, brainwash them and turn them into assassins or other kind of agents. He may find out that people with some sociopathic traits are better candidates for this, so he will target them. Now think the uber-villain is, uhm... (working for) your government :)
...not to mention the mislabeling of people with atypical social interaction patterns, like ones with mild/pseudo aspies which combined with the base rate fallacy brings serious mislabeling.
I'm sure this kind of electronic-psycho-profiling is already in use, and I even think it may have interesting side-benefits, like cool work being done in AI research for use in this (no better way to start "humanizing" and AI than to have it model human personalities and predict their actions), but there's tons of things that can go south with it for lots of innocent people that just happen to be "different" (like most people who end up making breakthrough discoveries or world changing inventions, you know...).