The Electronic Frontier Foundation and MuckRock have filed hundreds of public records requests with law enforcement agencies around the country to reveal how data collected from automated license plate readers is used to track the travel patterns of drivers. Today we are releasing records obtained from 200 agencies, accounting for more than 2.5 -billion license plate scans in 2016 and 2017.

Fewer symbols in America represent a sense of freedom more than an automobile on the open roadway. But in recent years, law enforcement and private companies have developed new technologies to automatically document our comings and goings and where we go in between. Today, police can access vast databases to search our travel patterns with just a few keyboard strokes.

Part of our strategy with this public records campaign was to seek two separate, uniform classes of documents easily exportable through Vigilant Solutions’ LEARN system. We provided each agency with a guide to producing these records straight from the user manual, which had been obtained through open records law by Mike Katz-Lacabe of the Center for Human Rights and Privacy. Most agencies were able to follow these instructions and provide the standardized records. Some did not and require a little work to decipher.

Analyzing ALPR data is an imperfect science, and we intend to update this dataset as inconsistencies are identified. If you encounter an issue, please email Dave Maass at dm@eff.org

Our research shows that 173 agencies from 23 states and the federal government accounted for roughly 2.5 -billion license plate scans in 2016 and 2017. The remaining 27 agencies refused to turn over reports on how much data they collected.