San Francisco's New License Plate Readers Are Leading to Arrests — and Concerns About Privacy

San Francisco police announced Monday that they’ve installed 100 automated license plate readers and have made several arrests since beginning to install them in March. The cameras sit near intersections and photograph every car, checking license plate numbers against a database of vehicles reported stolen or linked to a suspected crime.

Mayor London Breed touted the early results as a success, but advocates warn the technology, and others that San Francisco police are planning to implement, are a concerning shift toward mass surveillance without sufficient transparency.

“The early results we’re seeing are extraordinary because we are using 21st-century technology to help us combat some of our challenges related to crime, and it’s making a big difference,” Breed said in an interview with KQED on Wednesday.

Police have used the cameras to make several arrests, including a sexual assault suspect by San José police whose car was identified by ALPR cameras in San Francisco last week. They also arrested a woman who had a warrant after a camera identified her car.

“These 100 cameras have been a massive help to our police department,” Police Chief William Scott said in a statement on Monday. “In just a few weeks, we’ve received thousands of hits on stolen or wanted vehicles.”

Crime is down in San Francisco this year. There were 13% fewer violent crimes and 33% fewer property crimes from January through May compared with the same period last year, according to a Wednesday statement from the mayor’s office. Violent and property crimes are also down in all regions of the U.S. in the first three months of the year, according to data released by the FBI on Monday.

When asked about this, Breed maintained that the increased police response in the city is having an effect.

“The numbers — in terms of an over 85% arrest rate for homicides — that’s not happening in other cities around the country,” Breed said. “That is directly attributed to a lot of the work that we’re doing to increase our capacity to make arrests.”

Privacy concerns about mass surveillance

The technology is “eroding our civil liberties and our privacy,” Saira Hussain, senior staff attorney for the San Francisco-based Electronic Frontier Foundation, told KQED.

“When you have a network of hundreds of cameras around a densely populated city, you’re going to inevitably start to understand patterns of how somebody’s moving about and being able to track their movements at a very granular level,” Hussain said. “It starts to look like a mass surveillance technology that is basically a dragnet, and it is identifying everybody who is driving around — not the very, very small percentage of people who may be engaged in criminal activity.”

In response to a question about privacy, Breed said, “We are using what we have at our disposal to help us combat issues around crime. And sometimes there are trade-offs if we want to make sure that we are using this technology in a way that’s going to help make our streets safer.”

Hussain said she wants San Francisco police to share the data on how the technology has been used and what the outcomes have been.

“We should not just merely say, ‘Well, the technology exists, so we should just use it.’ I’d also again posit back on the police department. I want to see what the stats are,” Hussain said. “The studies that are out there have shown that actually automated license plate readers do not have a discernible effect on solving crime.”

A city ordinance requires San Francisco police to disclose an annual report on using ALPRs. Hussain and her colleagues submitted requests for public records for these reports, which the police could not produce. The city’s Sunshine Ordinance Task Force ruled last year that police were in violation of that ordinance (PDF).

The automated license plate readers, or ALPRs, are just one part of a broader shift toward using new surveillance technologies for policing in San Francisco.

“Our goal is to maximize our use of technology to fight crime more effectively and with more precision,” Scott said in the Monday statement. “We will be integrating our ALPR network with our other technologies, including technologies voters approved in March under Proposition E, like drones and public safety cameras.”

Proposition E loosened restrictions on police chases and authorized police to use drones and other technologies to combat crime. Breed said one target for the use of drones is sideshows.

“Drones are going to be really useful in terms of sideshows because not only will we be able to send drones into those locations, but they’ll be able to follow the various suspects once the sideshows have departed from the areas,” Breed said. “It’s so important that we continue to be as aggressive as we can, use all the tools that we have at our disposal in order to continue to reduce crime in San Francisco.”

Hussain said the increased use of these technologies serves to normalize mass surveillance.

“When you combine things like drones, and automated license plate readers, other types of technology, it really does begin to identify people as they’re moving about the city,” Hussain said. “And that really starts to look like, rather than an identifiable crime prevention tool, just trying to put everybody under a cloud of suspicion in order to pick out the very small number of incidents in which there is wrongdoing.”

Police plan to install 300 more readers throughout the city in the coming weeks.