The American Civil Liberties Union condemned police departments’ use of license plate scanners to track every movement of every vehicle in a report released Wednesday.
The report “found that not only are license plate scanners widely deployed, but few police departments place any substantial restrictions on how they can be used,” according to an ACLU press release.
Automatic license plate readers are scanners placed on road signs and bridges or in patrol cars that capture every license plate that passes them. The software then assigns time and location stamps the pictures and reads the license plate numbers to see if they match up with stolen vehicles and other crimes.
The issue, according to ACLU Staff Attorney Catherine Crump, is that “the spread of these scanners [are] creating what are, in effect, government location tracking systems recording the movements of many millions of innocent Americans in huge databases.”
According to the press release, ACLU affiliates filed 600 Freedom of Information Requests that asked federal, state and local agencies how they use the readers.
The results varied, but the press release notes that it was clear there are few restrictions on how these systems are used. “The approach in Pittsburg, CA, is typical: a police policy document there says that license plate readers can be used for ‘any routine patrol operation or criminal investigation,’ adding, ‘reasonable suspicion or probable cause is not required.’”
The license plate scanning systems do help police, but the majority of information they collect is on non-crime related vehicles. In Maryland, 47 out of one million plates are flagged as “potentially associated with a stolen car or a person wanted for a serious crime,” according to the press release.
There are no regulations on how long police can keep the license plate data. The Minnesota State Partol deletes records after 48 hours but Grapevine and Milpitas do not have deletion policy.
“The fact that some jurisdictions delete the records quickly shows that it is a completely reasonable and workable policy. We need to see more laws and policies in place that let police protect both public safety and privacy,” said Allie Bohm, ACLU advocacy and policy Strategist.
In the ACLU’s report, they made many recommendations for the use of license plate scanner systems.
“Police must have reasonable suspicion that a crime has occurred before examining the data; unless there are legitimate reasons to retain records, they should be deleted within days or weeks at most; and, people should be able to find out if their cars’ location history is in a law enforcement database,” the report said.
“Police departments should not use databases that do not have adequate privacy protections in place,” said Kade Crockford, director of the Technology for Liberty Project at the ACLU of Massachusetts.