But locating and arresting him took a little-known investigative tool: a vast system that tracks the comings and goings of anyone driving around the District.
Scores of cameras across the city capture 1,800 images a minute and download the information into a rapidly expanding archive that can pinpoint people’s movements all over town.
Police entered the suspect’s license plate number into that database and learned that the Pontiac was on a street in Southeast. Police soon arrested Christian Taylor, who had been staying at a friend’s home, and charged him with two counts of first-degree murder. His trial is set for January.
More than 250 cameras in the District and its suburbs scan license plates in real time, helping police pinpoint stolen cars and fleeing killers. But the program quietly has expanded beyond what anyone had imagined even a few years ago.
With virtually no public debate, police agencies have begun storing the information from the cameras, building databases that document the travels of millions of vehicles.