When Transit Agencies Spy on Riders

In 2015, workers installed a pair of cameras overlooking a parking lot in Oakland’s MacArthur Station. It’s the largest station in the Bay Area Rapid Transit (BART) system, and a major commuter hub. The cameras were fitted with automated license plate reader (ALPR) technology, part of a new generation of powerful surveillance tools used by law enforcement nationwide.

The cameras can scan more than a thousand license plates per minute and can be fixed nearly anywhere: on top of police cars, street lamps, bridges, street signs, malls, and even inside fake cacti. When a motorist drives by, the system runs the license plate through a “hot list” of plates that may be relevant to ongoing criminal investigations. If there’s a match, the system alerts law enforcement.

BART law enforcement officials wanted to use this technology to help combat a rash of car thefts and break-ins at BART stations. But BART leadership put the proposal on ice the next year, and the cameras were never supposed to be turned on. Except they were: For eight months in 2017, the cameras snapped up over 57,000 license plates numbers. They were only disabled after advocates alerted BART police, according to documents obtained by Oakland Privacy, a citizens’ collective that mobilizes around surveillance issues.

As the East Bay Times reported last week, this trove of sensitive ALPR data was then made available to ICE and other federal authorities, in a breach of  BART’s own “sanctuary” policy, which is designed to safeguard the rights of riders who may be undocumented. The transit agency has called it an “accident.”

“It’s another reminder that surveillance that happens locally doesn't stay local,” Matt Cagle, a technology and civil liberties attorney at the American Civil Rights Union (ACLU) of Northern California told CityLab. “Communities need to be thinking really comprehensively about where their data is going when they deploy these surveillance technologies.”

Privacy advocates have long objected to the use of ALPR. These systems retain information not just for cars of interest but for all motorists passing by, and that information can be readily accessed by others—from private individuals and news organizations to ICE or other law enforcement agencies. Connecting the dots between ALPR scans can create an intimate portrait of people’s daily routine, showing where and when a person went for medical treatments, immigration check-ins, or prayer meetings, or just where their favorite bar is. In 2014, the Minneapolis Star-Tribune used ALPR info to retrace the movements of the city’s mayor.

The fear is that this technology, like others in the past, can be used to surveil vulnerable populations. A 2013 ACLU report on the perils of license plate readers noted that “whole communities may be targeted based on their religious, ethnic, or associational makeup.” There’s some evidence that this is happening: In Sacramento County, for example, ALPR technology has been used by the Department of Human Assistance to track welfare recipients, even though incidents of fraud are statistically rare. And when the digital rights group Electronic Frontier Foundation (EFF) analyzed data on ALPR deployment in 2014, it found that it was used mostly in low-income black and Latino neighborhoods.

Apart from potentially violating civil rights, that kind of usage is incompatible with local sanctuary laws designed to protect immigrant communities: Both Oakland and BART’s board of directors have passed policies limiting local resources towards federal immigration enforcement.

“[LPR] basically enables the government to create a time machine and uncover the historical locations of anyone, including for instance, undocumented workers and their families,” said EFF’s Shahid Bhuttar. “In sanctuary cities like San Francisco and Oakland, we have made democratic decisions to protect them from precisely that kind of visibility to federal enforcement agencies.”

In 2016, BART’s then-deputy police chief told the East Bay Times that he felt ALPR technology would be especially helpful in combating local property crimes—burglaries, arson, thefts—which made up more than 90 percent of the force’s docket. Critiques of ALPR’s effectiveness as a crime-fighting tool note that past analyses have shown that the system’s rate of matching crime-link plates is very small—less than a 0.1 percent, in some cases. Still, some federal law enforcement officials defend its usage.

Mike Sena is the director of the Northern California Regional Intelligence Center (NCRIC), the law enforcement data-pooling center where BART’s ALPR data ended up. He told CityLab in 2016 that ALPR data gave investigators of murders and violent crimes a place to start tracking criminals, which was valuable even if it collects all this other extraneous information. ”If people could let me know which cars the criminals were driving, I would only look at those vehicles,” he said.

BART has recently shown much interest in beefing up its security capacity, especially since the July murder of black teenager Nia Wilson by a white assailant on BART, in what the agency’s police chief called an “unprovoked, unwarranted, vicious attack.” The incident captured national headlines, and in its aftermath, BART proposed an expansion of its transit surveillance apparatus to quell riders’ fears about the uptick in violent crime.

Advocates pushed back, arguing that that the agency needed to put in place privacy safeguards and oversight mechanisms before any such move. “We came together and we told the BART board that a rushed surveillance proposal is not the answer that the community wants,” Cagle said. “Rather, we want a conversation about real public safety solutions.”

A coalition of activists helped draft an ordinance that, among other things, requires a public debate before BART implements any new surveillance technology, and a clear set of rules on usage that accommodates privacy and civil rights concerns. Existing technology is to be grandfathered in to meet these requirements. On Thursday, a day after the news of the ALPR data breach came out, BART approved the legislation unanimously.

The agency’s willingness to enshrine public accountability is a victory for “every person who rides BART,” Cagle said in a statement after the vote. The ordinance can help ensure that the agency, which manages transit across multiple jurisdictions and has more than 400,000 daily riders, cannot use license-plate readers without first having clear usage, retention, and sharing policies.

He and other advocates caution, however, that this kind of law is still the exception, not the rule in U.S. cities—even in California, which is on the vanguard of the movement to rein-in spy tech in cities. In 2016, EFF could not locate privacy and usage policies for at least 90 agencies that may have been using this ALPR technology, even though a state law requires it. In addition, public records obtained by advocates at the Oakland Privacy collective show that as of June 2017, over 40 agencies have data-sharing agreements with NCRIC, which may include the transfer of ALPR data. The details these agreements are not very clear, critics have argued.

Apart from the handful of local jurisdictions in California and elsewhere that have implemented such community oversight laws, there isn’t much public knowledge, accounting, or oversight of surveillance, including of ALPR. Sometimes, even local officials are in the dark. How many agencies use this technology countrywide? To what ends? With whom do they share this information? Currently, it’s hard to say.

“These are questions that, quite frankly, shouldn’t require investigation to answer,” EFF’s Bhuttar said. “The harms [of unregulated spy tech] include not just theoretical risks to privacy. We’re ultimately talking about putting people’s speech at risk, their associations at risk, their freedom of movement at risk.”