I was raised in the South and I tend to Ma'am and Sir people and generally to be polite and respectful to folks I encounter doing their jobs. Cops might get a little extra respect, because they do work on our behalf that is often hard and sometimes dangerous, and, let's face it, they can make your life difficult if they choose.
I don't know the facts, but I don't find it hard to believe in theory that a celebrity professor at Harvard who just got off a plane from China might act like kind of a dick when confronted in his own home.
And I know that a black man in this country might have a very different relationship with the police than does my comfortable white self, and I can see how a black man might take umbrage and act like kind of a dick over something that would not come close to setting me off, which is not to excuse such behavior but to try to understand it.
And I know cops are people just like the rest of us, and sometimes they must get fed up and say, enough of this crap, buddy, you're coming with me, whether they really should do so or not.
But here's the thing that's surprised me as I've done an unscientific and statistically-invalid survey of opinions about dealing with cops: the number of people who accept without question that it's OK for a police officer to arrest you on your own property for acting like kind of a dick. Not acting in a threatening way, or failing to comply with an investigation or something, just being kind of a mouthy jerk.
I'm not talking about the legal right to arrest, but the okayness of it in some broader sense. Americans just don't seem to be as libertarian as I expected them to be on this subject.