Between the emphasis by the media of cops shooting unarmed blacks in urban neighborhoods for petty crimes, and hateful rap lyrics promoting cop killing...it's tough. It pits the people against the cops and cops against the people. That's never a good thing.
It makes officers more wary and perhaps more suspicious or aggressive toward the general public. After all, most cops are just trying to make it home alive every night. They have a right to be on the offensive, their life depends on it.
But to blindly say that every cop in every city in America is Officer Friendly and never has a corrupt thought, or wouldn't ever think of abusing their power, I think that's an equally unfair representation. If officers have broken the law it should be reported, we shouldn't bury it or withhold that information from the public.