I'm sure many of them are. But equally many are mere functions of human nature. The long-term impacts of individual actions on the power of the police-force as

I'm sure many of them are. But equally many are mere functions of human nature. The long-term impacts of individual actions on the power of the police-force as a whole are both non-obvious and very slow. In particular, I really doubt that the social pressure to empower the institution, transmitted down the chain of command, has more impact on police officers than the violence and abuse they witness first- or second-hand.