I don't think that's entirely true.police suck they are more corrupt than anybody.
Lemmy edumakate you about a little Freudian psychology about how we choose "right and wrong"
People are motivated by three basic forces-what Freud called "Id", "Ego", and "Superego"
"Id" is our hedonistic side. I want steal that, or Eff that, or kill him/her
"Ego" is our fear of the negative consequences we will suffer if we are caught doing something wrong (prison, pain, death, Hell, etc)
"Superego" is our desire to do the right thing despite the positive or negative consequences (religious or secular)
Most cops START OUT with a normal mix of those three forces-maybe with a little bit more idealistic "superego"
The problem with scumbag cops is that after a few years, there are forces within and outside the police department that do two things to them
1. Give them a sense of entitlement- "Everybody hates me...I risk my life and nobody appreciates it...I see people doing 'the wrong thing and they have more than I do'..." This diminishes the "Superego"
2. They see their cop buddies don't "turn into pumpkins"- They see other cops "do the wrong" things usually without negative consequences. Cheating on their wives, lie in court, theft, false police reports, father bastard children, etc. This diminishes the "id"
In conclusion, they turn into the kind of scumbags they arrest