If you keep calm and state legalise, they wilt. Same thing happens in every scenario where you know more than the opposition does
If they beat you for remaining calm, you win.
Remaining calm is the key to civil disobedience
I would just add the camera is key.
To a DA and most juries a cops word is gold.
The cops first reaction to something like this is to accuse you of being a lawyer in a mocking way. The irony is that there are so many laws that out side of common sense legal issues cops are far from legal experts. And of course even lawyers don't have the law memorized.
But if there is no film they still don't give a fuck and will just do as they please.