After you have been in an accident, it is a good idea to call the police to come to the scene. The police will create an official accident report of the incident. This report will document what happened in the accident as well as the accident scene. Even if the accident is relatively minor, you may still want to call in law enforcement so as to protect your legal rights in any subsequent disputes over liability.
In addition, if you have been the victim of a crime such as a hit and run or if you were injured by a drunk driver, you will want to contact the police to report the incident.