how do you guys deal with police harassment?

Lately it has been getting pretty bad in some citys with cops shoving me, calling me names, detaining me needlessly. ONe cop told me it was illegal to photo the police and grabbed my camera. Another threaten me with violence if i continued photographing in a public space.

Has anyone successfully sued a city or their police force? also stories about police encounter. I imagine landscape photographers don't have as many run-ins with police as street photographers.

Pic related. I saw what to me looked like a man with no legs being harassed by the police. When I tried to ask the disabled man if he was okay I was immediately told to leave the area in a very hostile manner as the police officer kept getting in my face and moving me away.