"We have to realize that for every ass-hole wearing a badge, there are probably hundreds of policemen just like Rick."
And for some reason the guys like Rick put up with them--allow them to do their damage to the uniform. I've seen it with my own eyes.
You're point is well taken, but I would take one exception. I think it's the guys NOT like Rick who put up with them. Quite a few guys like Rick will roll over on a bad cop in a minute. I've been on the witness stand myself to testify against a dirty cop (he was lawyered up and the jury acquitted him, but at least he stayed fired).
On the other hand, I had a friend join Chicago PD. He left within 8 months saying he couldn't abide by what he saw. Told me IAD wanted him to go undercover but figured either he or his family would end up dead. That was his story, of course, but it's consistent with what I've heard elsewhere.