A new technology allows police to quickly run license plates from passing cars, but some officials and activists say cities should think again about how the data might be used.
The license plate readers, or LPRs, automatically scan the license plates on passing cars and check them against lists of stolen cars, Amber Alerts or outstanding warrants. Some area law enforcement agencies store the data they collect through LPRs, generally for a month or a year, although retention policies vary by jurisdiction.
Rockville City Council member Tom Moore said the scanning devices did not get a lot of policy attention when they first arrived. Now, he thinks the mayor and council need to discuss how to handle the information they collect.
“These things are popping up all over the place,” he said. “There are a lot of national security grants throwing these things out to local departments.”
In February, the Gazette reported that there were 36 LPRs on squad cars in Montgomery County, including three operated by Rockville police. Rockville’s LPRs hold their data for 30 days, then automatically delete them, according to an August memo from the Rockville police chief. The information from Rockville’s LPRs also goes into a server operated by Montgomery County police, which then passes it on to the Maryland Coordination and Analysis Center, a joint initiative made up of partners in federal, state and local agencies.
The Maryland Coordination and Analysis Center purges its LPR data after one year, unless it has reason to believe the data will become evidence, according to the memo. Montgomery County is reviewing its retention policy, but preliminary recommendations include keeping LPR data online for one year, then archiving it offline, the memo said, and only allowing law enforcement access to the data.
Moore takes issue with the practice of keeping records from the devices indefinitely.
“We don’t keep permanent locational records of people who haven’t done anything wrong or aren’t suspected of doing anything wrong,” he said.
Moore said Rockville is not under any obligation to share data or images from LPRs with the county. Although he wants to hear from privacy advocates and police before proposing a policy for the city, he said he is concerned about the county’s practice of keeping archived LPR records indefinitely.
“The only way to make sure that this data is not misused in the future is if it’s not there,” he said.
Rockville City Manager Barbara Matthews formerly served as city manager of Takoma Park, which does not share data from its LPRs with other agencies. During her time there, Matthews said, she and the city’s police chief recommended not sharing the information it collected with the state.
She said Takoma Park’s situation is a bit different from Rockville’s, as county police do not operate in Takoma Park.
Matthews said storing information from license plate readers for 30 days, as Takoma Park does, can help police identify patterns in a series of burglaries and car break-ins.
“I think it’s a wonderful technology that has a lot of benefits to any law enforcement agency,” she said. How long to store the information and who gets access to it are policy questions that the mayor and council handle, however.
Rockville Police Chief Terry Treschuk also said the mayor and council will review and set an LPR data retention policy. Overall, he said, LPRs benefit law enforcement agencies, and he thinks the Maryland Coordination and Analysis Center has a good policy for how it handles LPR data.
“I think the LPRs are a great benefit to law enforcement,” he said. “I think we are part of a regional effort.”
Treschuk said his department is compiling statistics on how many arrests or citations LPRs have led to in preparation for a future mayor and council briefing.
In July, the American Civil Liberties Union sent public information requests to law enforcement agencies in 38 states, including Maryland, seeking information on how they use LPRs. David Rocah, staff attorney for the ACLU of Maryland, said because LPRs are a relatively new technology, lawmakers need to address how to protect people’s privacy.
“There is a lack of privacy protections written into existing law that govern this kind of data, and that’s a significant problem,” he said.
Rocah said officers only need to store data from LPRs for a few seconds in order to run plate numbers against existing databases. That technology helps law enforcement by augmenting officers’ own eyes and speeding up the process of running plates, he said.
However, as prices rapidly decrease for readers and data storage, Rocah said, agencies will be able to store vast amounts of detailed data indefinitely, giving them a detailed picture of who is where and when.
“That’s data that the government frankly has no business having absent individualized suspicion,” Rocah said.
Matthews said she anticipates that the Rockville mayor and council will discuss how the city uses license plate readers at the end of February.