Westchester Police Are Tracking Millions of Drivers

Leah Nelson is a law-abiding retiree who drives her car throughout Westchester County as she goes about her day and fights for causes that matter to her: police reform and racial justice. Ms. Nelson has no reason to believe she is part of an ongoing criminal investigation, yet the Westchester County Police Department (WCPD) has tracked her whereabouts almost 1,000 times over the past two years in its massive vehicle surveillance system.

This surveillance system utilizes hundreds of automatic license plate readers (“ALPRs”) and artificial intelligence (“AI”). Leah is not unique. If you drive through Westchester County, then it is likely that you are in its surveillance system, too. Every year, the WCPD collects and analyzes data on millions of innocent drivers. With this data, police officers can track their daily movements to stores, doctors’ appointments, religious institutions, political activities, and much more. This data is then available to outside law enforcement agencies – including ICE.

Leah is part of a growing number of New Yorkers alarmed by this massive invasion of their privacy, and she’s fighting back. She and three other Westchester drivers are being represented by the NYCLU, the Knight First Amendment Institute at Columbia University, the Policing Project at New York University’s School of Law, and Freshfields US LLP, in a class action lawsuit seeking to curb the WCPD’s mass vehicle surveillance system.

How Do License Plate Readers Work?

ALPRs are devices that can be mounted on police cars or fixed on poles along the roadside to scan all vehicles passing by. Unlike red light or speed cameras, which are at least theoretically triggered by violations, license plate readers continuously and indiscriminately record data on each and every vehicle regardless of the driver’s conduct.

They capture, at minimum, the license plate number of a vehicle as well as the date, time, location, direction, and often other characteristics including make, model, color, roof racks, and stickers. Westchester’s system is able to capture still images and video of drivers and any passengers in the vehicles.

While license plate readers have been around for decades, they have proliferated around the country and become more advanced. Today’s technology allows law enforcement throughout the country to aggregate, analyze, and share much greater amounts of drivers’ data and even predict where people will go in the future based on their past travel behaviors.

The WCPD contracts with a technology company called Rekor to provide the software necessary for its Vehicle Surveillance System. Using Rekor’s AI-powered tools, the WCPD can instantly analyze vast amounts of vehicle surveillance data in its database to reconstruct detailed information about the routines, habits, and daily lives of Westchester drivers.

Sarah Moore, another plaintiff, is a teacher, mother, and advocate for immigrants’ rights. She participates in a mutual aid group and observes ICE activity. Earlier this year, ICE agents followed her car and briefly detained her. Because ICE has her license plate number, they can track her through the WCPD’s Vehicle Surveillance System. She is now terrified while driving, knowing that she is being watched.

License plate readers can also reveal a person’s presence at sensitive locations like clinics that provide abortion and gender-affirming care, places of worship, psychotherapists’ offices, or Alcoholics Anonymous meetings. The WCPD’s tracking of this intimate information is a violation of people’s privacy and their civil rights.

How is the WCPD Violating Drivers’ Rights?

While there may be some legitimate investigative purposes for ALPR data, such as searching for stolen cars or missing people, the amount of information the WCPD stores, analyzes, and shares vastly exceeds these limited purposes.

In 2024, the WCPD collected more than 264 million recordings – almost entirely from innocent drivers. More than 99 percent of those recordings were unrelated to any suspected crime or investigation. And studies show that even when ALPR data triggers a “hit” on law enforcement’s “hot list” of cars connected to suspected crimes or investigations, it frequently isn’t accurate. A 2018 report from California found that around 35 percent of all hits were actually false positives.

Whether a person’s license plate is connected to a “hot list” or not, the WCPD holds onto the data for two years, adding it to a database containing approximately 1.6 billion vehicle recordings. The WCPD provides at least 55 outside agencies, including ICE, with access to its ALPR data – which ICE could use to track someone down for detention or deportation, or, as with Sarah, to harass them in an attempt to chill their advocacy efforts.

Through its agreement with Rekor, the Department also shares its data with law enforcement agencies across the country. This puts people at greater risk of an agency abusing their data. It also poses a danger for people who cross state lines to receive abortion or gender-affirming care. In one case, Texas authorities used out-of-state ALPR data to track down a woman they believed had self-administered an abortion.

Finally, companies could sell people’s data, or hackers could steal it, as long as it remains in the database. The WCPD holds people’s data for two years, though they have held data from one plaintiff for even longer.

While license plate readers affect all Westchester drivers, they do not do so equally. As with other forms of police surveillance, authorities disproportionately target Black and Brown communities. We believe that ALPR cameras are saturated in the predominantly Black and Latine neighborhoods to the south and along the Bronx border.

As worrying as the information we do know is, there’s also a lot we still don’t understand about how the Department uses millions of drivers’ data. The WCPD has not revealed the location of its cameras or named all of the law enforcement agencies with whom it shares its data. We also don’t know how the WCPD is using AI technologies like “convoy search”, which tracks cars seemingly travelling together, and interdiction, a technology that identifies cars travelling “suspicious” routes.

We do know that the Department lacks meaningful guardrails to protect residents from overreach. An officer can comb through two years of a driver’s data without a warrant or even a minimum requirement of suspicion. And the Department doesn’t give officers any training on how they’re supposed to use the database.

The county legislature has never explicitly given the Department authorization to run the system, meaning the WCPD is using it without proper democratic authorization.

The NYCLU, Leah, Sarah and our partners filed this suit because WCPD must change how it collects, holds, and uses license plate data and be transparent about these policies. Westchester residents deserve to be able to go about their daily lives, including accessing medical care and volunteering to help community members, without police tracking their every move.