Local police are potentially able to gather information from several databases, according to Slate. Police generally have access to some warrant databases, to the state's Department of Motor Vehicles or its equivalent, and to local police records.
There is no single database police use to find information on an individual, reports Slate. The ability to look up a person's federal and state criminal history varies from agency to agency based on the law. The National Crime Information Center database is directly accessible from police vehicles at some police departments, while other departments require written requests to be submitted prior to accessing this source.