Being stopped by the cops is scary. This Instructable gives you everything you need to know to safeguard your rights when you are dealing with the police.
All of the information here is straight from the American Civil Liberties Union.
Step 1: General guidance for dealing with the police
1. What you say to the police is always important. What you say can be used against you, and it can give the police an excuse to arrest you, especially if you badmouth a police officer.
2. You must show your driver's license and registration when stopped in a car. Otherwise, you don't have to answer any questions if you are detained or arrested, with one important exception. The police may ask for your name if you have been properly detained, and you can be arrested in some states for refusing to give it. If you reasonably fear that your name is incriminating, you can claim the right to remain silent, which may be a defense in case you are arrested anyway.
3. You do not have to consent to any search of yourself, your car or your house. If you DO consent to a search, it can affect your rights later in court. If the police say they have a search warrant, ASK TO SEE IT.
4. Do not interfere with, or obstruct the police, as you you can be arrested for it.
Think carefully about your words, movement, body language, and emotions.
Do not get into an argument with the police.
Anything you say or do can be used against you.
Keep your hands where the police can see them.
Do not run. Do not touch any police officer.
Do not resist even if you believe you are innocent.
Do not complain on the scene or tell the police they are wrong or that you are going to file a complaint.
Do not make any statements regarding the incident.
Ask for a lawyer immediately upon your arrest.
Remember officer badge & patrol car numbers.
Write down everything you remember ASAP.
Try to find witnesses & their names & phone numbers.
If you are injured, take photographs of the injuries as soon as possible, but make sure you seek medical attention first.
If you feel your rights have been violated, file a written complaint with police department internal affairs division or civilian complaint board, or call the ACLU hotline, 1-877-6-PROFILE.