In the 2000s I knew a guy who was transitioning to software development after working in HR at a large American police department. He told me you couldn't become a cop unless you had a mental illness. They psychologically screen candidates to filter out people who have too much empathy. They would reject you if you said you had a close relationship with your mother, for example. They wanted people with aggressive tendencies. They loved it when someone had a superhero tattoo or had a parent die when they were a child.

People always comment that we need to do more screening before people become cops, do more training. The screening and the training are the problem.

It sounds like that guy may have been exaggerating a bit. Aggressive people are a liability. Especially in law enforcement. Not just to the department but to fellow officers. They stir shit up and it is dangerous and annoying.

Cops do need more training, like dramatically more training. I think the screening process is trying to solve a really difficult problem. You don't know if/how someone will be corrupted when they have a little bit of power. Or how they will change over time.