I think the police officer profession is made to order for the narcissist type. What needs to be done is screen this type of personality by psychological testing. How you do that is for the experts because the narcissist will try to figure out how to beat the test.
We have a bifurcated folly going on here. In a parallel thread there is the story of an officer that got offed at random by a #BLM zealot.
The overall story here is not a police problem or even a crime problem as much as it is a godlessness problem.