Legislation would require educators to report potentially dangerous people to police

[Jackpine Radical]

5. The problem with this whole approach is that the base rate of bizarre behavior

is much, MUCH higher than the base rate of mass/serial homicide.

Suppose there are 100 mass killings a year in the US, and about 5 in 100 people exhibit worrisome symptoms.

Further suppose that, eliminating women and young children as potential killers, you end up with a total pool of 150 million potential killers (males in the right age groups).

If 5% of those 150 million people are screened in for further examination based on their worrisome symptoms, you have a pool of 6 million potential killers, of whom 100 will actually commit hienous crimes. What are you going to do--treat/confine 6 million in order to stop 100? And that's assuming that your net doesn't let any slip through. It would be remarkable if your net were good enough to identify half of the potential killers (the others not having shown sufficient overt signs to warrant inclusion). So now you are confining or otherwise majorly interfering with 6 million people in order to stop 50 of them. In order to stop one mass murder, you will need to somehow intervene on 120,000 non-killers who "look dangerous" but in fact aren't.

And all of this is a best-case scenario.

About 3% of the population is psychotic (schizophrenic, severely bipolar, etc.), and would surely be among the ones netted up. Yet the incidence of homicide among schizophrenics is about the same as in the general population. You will have spent a whole helluva lot of money & resources rounding up a very large number of people who are at no greater risk of doing horrific things than is the general population.