Once again, I'd only be guessing, because I'm obviously not a psychologist. But that's always been my assumption: we don't want to have people out there potentially using force of any kind, including firearms and deadly force, who don't fit the psychological profile that's required.
We do fairly extensive testing. It's called the MMPI. I don't know what all that means, but ultimately people are turned down, including children of our own officers, for the reason that they did not pass psychological tests. So we take it very seriously.