A traffic stop, step by step

Pull over promptly and somewhere safe, turn off the engine, and if it is dark, turn on the interior light. Keep your hands where they can be seen, normally on the steering wheel. Ask before reaching for anything, and say where you are reaching: the glove box, your pocket, the console.

Almost every practical guide from law enforcement agencies and from civil-liberties organizations agrees on this part, which is unusual and tells you something. Sudden unexplained movement is the thing that changes a routine stop into a dangerous one.

A driver is generally required to produce a licence, registration, and proof of insurance on request. That is a condition of the licence, and refusing it is its own problem.

Questions are a different category. "Where are you coming from?" and "Do you know why I stopped you?" are questions, and the Fifth Amendment privilege against self-incrimination applies. You can decline to answer, politely. Some states have stop-and-identify laws that require a person to give their name in certain circumstances; the rest of the conversation is generally still voluntary. Passengers may be asked for identification, and in many states are not required to provide it unless the state's stop-and-identify law applies.

Write down what happened as soon as you safely can: time, location, what was said, the officer's name and badge number if you saw them, the patrol car number, and any witnesses. Memory degrades quickly and specifically.

If something went wrong, the routes are a complaint to the department or a civilian oversight board, a conversation with a lawyer or legal aid organization, and, for a ticket, the court date printed on it. Every one of those is a better venue than the roadside, and all of them work better with notes written the same day.