Contempt of Cop. It’s not an official crime. You’ll never find it listed in the statute books. But it’s real. Just ask the right people. If a cop believes that you are not being sufficiently respectful (as the cop defines “respectful”) you are in trouble. If you were stopped while you were driving, you can be cited for “weaving”, bad equipment on the car, broken taillights, whatever. If you were walking, the list of problems including failure to disburse, failure to identify yourself, etc. grows.
And then comes the search. A proper search can be done reasonably or otherwise. There are lots of tricks cops know and use when they want to antagonize you. Then the charges are upgraded to resisting arrest, assault on a police officer etc. And you are in BIG trouble.
So, what to do when the police stop you? Be respectful. Shut up! Don’t say anything you don’t have to say. If you are not sure what to do, don’t do anything. If the cop wants you to talk he’ll tell you to talk. And then you can reply, respectfully, that you prefer not to talk without a lawyer present. But Respect is everything on the street and the cops will insist on it–especially from young people and people who do not speak English with the same accent the cop does.