Please note that by playing this clip YouTube and Google will place a long term cookie on your computer.
Automatic license plate recognition (ALPR) systems are flying off the shelves nationwide, thanks in large part to federal government grants to state and local police. But while DHS, DOJ and even the military are doling out millions of dollars in cash for these systems nationwide, attendant conversation at the local level about the privacy implications the technology presents -- and information about any federal guidance to states and locals on data and privacy policies -- is seriously lacking.
The stakes are high.
License plate trackers work very well, and police love them. Departments report immediately improved stolen car and outstanding warrant statistics nearly everywhere the machines are deployed. CSI-style, dramatic, blockbuster ALPR-success stories pepper police talking points: here the technology solved a murder, there it led police to a kidnapper in time to save the kidnapped mother and child.
The machines, either affixed to stationary locations like telephone poles, or mobile, on the front and back of police patrol cars, can record license plates at a rate of thousands per minute. An ALPR-equipped squad car parked outside a church or mosque could suck up the plate data of all motoring worshippers while the police officer inside reads a book or takes a nap. A mobile system on a highway can record and transmit the plate data of every car that passes it, potentially hundreds of thousands a day.
When the camera snaps a photo of each passing license plate, it also marks the GPS location and time and date of the interaction, storing a unique file for each catch. The system converts the plate number to machine readable text and automatically runs it against any number of law enforcement, homeland security or other databases -- including in some places, IRS records.
Police may also manually enter license plates for the system to watch out for.
In Northern Virginia recently, a man reported his wife missing, prompting police to enter her plate number into the system.They got a hit at an apartment complex, and when they got there, officers spotted her car and a note on her windshield that said, in essence, “Don’t tow, I’m visiting apartment 3C.” Officers knocked on the door of that apartment, and she came out of the bedroom. They advised her to call her husband.
Like with most surveillance technology in the 21st century, the devil that ALPR presents is in the details: data policy and accountability mechanisms.
Police could deploy ALPR with very clear guidelines and policies that narrow the likelihood for system abuse or violations of our privacy. That's happening in Maine, where state legislators mandated deletion of all captured plate data after 21 days. But that's not the case in most places, with potentially disastrous consequences if we don't do something about it, and fast.
The biggest risk posed by limitless ALPR data collection is that police will be able to retroactively track motorists' movements throughout our cities, towns and states -- or even throughout the country. Many police departments -- and most states -- lack clear guidelines requiring that officers delete "non-hit" data after a reasonable amount of time. Without such guidelines, police will collect and in some cases already are collecting vast troves of plate data on people not suspected of having committed any crime.
Police officers are open about why they want to keep all the data. A Tennessee journalist spoke with police officials who bluntly advocated mapping ALPR data for intelligence purposes:
Police see far more potential in a related map database that catches all of the scanned license plates in Gallatin, Hendersonville and Sumner County, even those that didn’t match the criminal lists. With that map, a detective can type in a license plate number seen at a crime scene — or even just a partial tag — and search for places where it has been spotted by cameras.“That’s the whole key: the databases,” said Hendersonville police Lt. Paul Harbsmeier. “If we collect so many tags just for Hendersonville, it doesn’t do any good for anybody else. Let’s say we catch somebody that was involved in residential burglaries, we might check that tag to see if they were in the vicinity of any other burglaries.”
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.