As the use of license-plate-recognition camera technology to gather and record drivers’ movements started becoming widespread in the United States, people asked a number of questions about the privacy, civil liberty and security implications about the surveillance technology. Last year, the Center for Investigative Reporting looked into privacy questions concerning the use of license-plate readers and found that “a leading maker of license-plate readers wants to merge the vehicle identification technology with other sources of identifying information.” A couple of years ago, the American Civil Liberties Union released a report (pdf) on license-plate readers and how they are used as surveillance devices.
And law enforcement is concerned about how such tech affects privacy rights, as well. In 2009, the International Association of Chiefs of Police issued a report on license-plate-recognition technology and said, “Recording driving habits could implicate First Amendment concerns. [...] Mobile LPR units could read and collect the license plate numbers of vehicles parked at addiction counseling meetings, doctors’ offices, health clinics, or even staging areas for political protests.” The privacy and civil liberty questions have led to the cancellation of some license-plate-recognition surveillance programs, including ones in Boston and by the Department of Homeland Security.
One of the biggest questions is: What happens to all the data on innocent individuals? Often, we don’t know what the restrictions are on the collection and use of the data. We have learned some information about what some groups do with the data. Last year, the Washington Post reported that commercial databases gather such location data to sell. In 2013, the ACLU review of license-plate-reader camera technology found that “the approach in Pittsburg, Calif., is typical: a police policy document there says that license plate readers can be used for ‘any routine patrol operation or criminal investigation,’ adding, ‘reasonable suspicion or probable cause is not required.’ [...] As New York’s Scarsdale Police Department put it in one document, the use of license plate readers ‘is only limited by the officer’s imagination.’” In 2011, the Washington Post reported that Virginia used the license-plate scanning technology for tax collection.
Now, as a result of the public records request, Ars Technica has received the entire license-plate-reader dataset of the Oakland Police Department, “including more than 4.6 million reads of over 1.1 million unique plates between December 23, 2010 and May 31, 2014.” And it’s interesting to see what personal information can be gleaned from the surveillance data.