Police in the rest of the country behaves in worse ways, it just that they don't usually get put under a microscope unless they kill a sufficiently photogenic person.

The system of checks and balances between police and the people they are supposed to be accountable to is completely broken.

(Even if by some miracle, you do manage to hold a small-town cop accountable for something he did, he can make it his life's goal to personally make yours a living hell. At least in a big city, you're not going to be driving past any particular cop, every day, on your way to work.)