Most of the "not bashing cops - bashing cops" threads start out with some guy that had an encounter with the police. Often it's for a traffic stop where they absolutely state that they didn't do whatever it was they were stopped for.
Given their attitudes on those forums in general, I rather doubt that the police are the ones with the attitude problem. Every time I've been stopped by police there have been two things in common. First, I was doing something worth being stopped for. Second, except for the very first time, 40 years ago, I left without a ticket in hand.
I've found that honesty and politeness go a long way with most police officers.