There's one very simple thing you can do (works for teachers as well): pay people a lot more, and then be a lot more selective. The more you pay, the more selective you can be. "In it for the money" beats "in it for the power trip" hands down.
But jobs in the so-called security services always attract that kind of people. This doesn’t go away by paying more. You’ll just get smarter applicants who hide it better.
