What the Flock? Understanding the license plate readers seemingly everywhere

Whether you realized it or not, you’ve almost certainly driven by an automated license plate reader.

The futuristic-looking devices are mounted to traffic signals, light posts and overpasses. Some police cars even feature them. They’re used in some garages and planted outside some businesses.

The cameras can be used to find stolen cars and missing people, and even for mundane tasks such as paying tolls and letting vehicles out of parking garages. But recently rage has riveted on one license plate reader company, Flock Safety, with news articles highlighting how law enforcement has abused the technology. Dozens of police officers across America, for example, have been accused of using Flock to spy on past or present romantic partners.

Flock’s presence in Maryland is growing, even if its technology is hardly novel. Police have been using license plate readers for at least a decade.

Here’s what you need to know:

Why do police use automated license plate readers?

Motor vehicles are involved in 75% of crimes every year, according to the International Association of Chiefs of Police.

Law enforcement officials say automated license plate readers are a powerful tool for solving cases, particularly for stolen auto and missing persons investigations.

Baltimore Police’s fleet of license plate readers flags an average of 175 stolen vehicles and 25 vehicles associated with wanted persons every day, said Lindsey Eldridge, the department’s chief spokesperson.

The technology has helped investigators solve everything from burglaries to murders, Eldridge said.

Which local agencies are using Flock or some other reader?

Many agencies across Maryland use automated license plate readers, and some specifically say they use Flock cameras.

The Baltimore Police Department uses cameras from Leonardo US Cyber and Security Solutions and is adding some from Axon, a major supplier of public safety technology such as body-worn cameras.

Howard County uses license plate readers made by Leonardo and Axon. It operates 27 ALPRs.

Baltimore County Police have used Leonardo license plate readers for about 20 years, said Detective Trae Corbin, a department spokesperson.

The Anne Arundel County Police Department uses multiple kinds of readers and says Flock is its “largest” system. Anne Arundel Police say they don’t use the cameras’ video or artificial intelligence capabilities and use the cameras only to capture still images.

Holly Beilin, a spokesperson for Flock, said this year that she thought Anne Arundel County was the company’s largest municipal customer in Maryland.

“They are not unique,” she said, “but they are a flagship agency, I would say, in tracking their crime statistics really well.”

How often do police use this technology?

The cameras snap pictures up to hundreds of thousands of times every day, according to annual audits submitted to the Maryland General Assembly, which mandated such reports in 2014.

Maryland Transportation Authority Police had the most reads in 2025, the most recent year for which data is available, with 296 million.

That’s a dramatic increase from 2015, the first year police were required to submit such data to the state, when police for the authority, which runs the state’s tolled bridges and tunnels, recorded 1.5 million reads.

Baltimore Police didn’t have license plate readers in 2015, but last year their 125 cameras recorded just shy of 278 million reads.

Anne Arundel County Police recorded the most reads in the state in 2015 with 21 million, a figure that grew to 29 million in 2025.

Why is Flock getting so much attention?

Automated license plate readers have been around for years, but Flock specifically has been subject to public scrutiny. That’s likely in part because of multiple instances of police officials abusing the system, leading to internal investigations and arrests. There also have been concerns about the technology behind Flock being used to augment immigration enforcement.

Jay Stanley, senior policy analyst with the American Civil Liberties Union, said the “heart of the issue” with Flock cameras is that they’re “a mass surveillance system.”

“They are collecting data on a population level, about people’s movements and whereabouts without any individualized suspicion,” Stanley said in an interview this year.

The company also “boasts” about its software’s ability to use artificial intelligence to analyze data, Stanley said.

“Anybody can find themselves, because of some black box computer algorithm, in the crosshairs of law enforcement,” he said.

Why don’t people like Flock and other readers?

Growing concerns about privacy and potential abuse have led some local governments to cancel their contracts with Flock and others to cover the cameras with plastic bags.

In some places, automated license plate readers have been vandalized or destroyed. They’ve also become the target of social media videos suggesting people destroy the cameras.

Some organizations, including one called DeFlock, host open-source maps that show the locations of such readers.

“The map helped people to visualize the scope of the problem,” said Ed Vogel, a member of DeFlock. “People better understand now how extensive this network is and the implications of that.”

Does Maryland regulate license plate readers?

Yes and no.

In 2014, the General Assembly passed a law requiring local and state law enforcement agencies to conduct an annual audit of their license plate reader usage and submit it to lawmakers.

The same law mandated that police can use license plate readers only for “legitimate law enforcement purposes” and created penalties for violations.

State lawmakers added more regulations in 2024, focusing on the data the readers collect. The recent law codified that the information collected is exclusively owned by those agencies and may not be sold. There are penalties for violations.

Local and state law enforcement agencies also put protocols in place for their officers’ use of license plate readers, such as requiring a case number for a search.

The private use of the readers, however, is unregulated in Maryland.

Several lawmakers involved in past legislation said they would look to explore that gap in the 2027 legislative session.

Sen. Charles Sydnor III, a Baltimore County Democrat, said he is committed to exploring regulations for private sector license plate reader usage.

“I think it’s a legitimate question to ask the utility of why they feel they need to do this and what are they doing with the data,” Sydnor said.

Republican Sen. Steven Hershey, the legislative chamber’s minority leader, said he’s been hearing from constituents worried about the growing reach of license plate readers.

“People are concerned about what information these Flock cameras are collecting and how that data is being used,” the Eastern Shore lawmaker said. “We understand that these types of cameras are regulated for law enforcement. However, they are not for the private sector and that’s certainly something we should address in the next legislative session.”

Del. N. Scott Phillips said the state must focus on regulating the private sector’s use of data captured by the readers.

“My personal sense is that the genie is out of the bottle,” the Baltimore County Democrat said. “I don’t think that we can regulate at this point the capture of information, because once again we have cameras everywhere.”