More than 250 cameras in Washington, D.C., and its suburbs scan license plates in real time, helping police pinpoint stolen cars and fleeing killers. The Washington Post says the program has expanded beyond what anyone had imagined a few years ago. With almost no public debate, police store information from the cameras, building databases that document the travels of millions of vehicles. Police say the tag readers can give them a critical jump on a child abductor, information about when a vehicle left or entered a crime scene, and the ability to identify a suspected terrorist's vehicle as it speeds down the highway, perhaps to an intended target.
The capital city has more than one plate-reader per square mile, the nation’s highest concentration. Police departments are trying to decide how long to store the information and how to balance privacy concerns against the value the data provide to investigators. The data are kept for three years in Washington. Citing “quite a large database of innocent people's comings and goings,” Jay Stanley of the American Civil Liberties Union contends that, “the government has no business collecting that kind of information on people without a warrant.”