By Michael Huggins

Every day, Automatic License Plate Readers (ALPR) capture millions of license plate images, which are stored in third-party databases. ALPRs have been used by law enforcement and state agencies to recover stolen vehicles and as a method of electronic toll collection on roads. Privacy activists, however, are concerned that state law enforcement may use ALPRs as a surveillance tool to track drivers’ locations and store images of drivers and their passengers. They argue that ALPRs may be used to collect information about individuals engaging in lawful activity, such as attending a peaceful gathering, or who pose no security threat.

For example, the Virginia State Police used ALPRs to record not only the license plates of vehicles attending President Obama’s inauguration, but entire campaign rallies for President Obama and former Alaskan Governor Sarah Palin as well. And in San Leadro, California, police used ALPRs to monitor Mr. Mike Katz-Lacabe’s Toyota Tercel, even though he had not been charged with a crime. When Katz-Lacabe submitted a public records request, he obtained 112 photos of his vehicles dating back two years. He was surprised to learn that he could identify people in the photos. Indeed, he was able to identify himself wearing one of his Berkeley shirts.

Many have raised concerns that the federal government can also access this information. In a 2009 internal Drug Enforcement Administration (DEA) memo, the DEA stated that a national LPR initiative was designed to “combine existing DEA and other law enforcement database capabilities with technology to identify and interdict conveyances being utilized to transport bulk cash, drugs, weapons, as well as other illegal contraband.” Over the past several years, the U.S. Department of Homeland Security has given state law enforcement agencies over $50 million in federal grants to implement ALPR systems.

Proponents of ALPRs argue that (1) driving in public is, by definition, not a private activity; they argue that drivers do not have a reasonable expectation of privacy when they leave their homes and drive their cars. Proponents also argue that (2) license/plate location data only identifies a vehicle, not a person.

While it is true that no expectation of privacy is maintained for property and personal effects held open to the public, the government must exercise restraint when tracking and storing the license plate images. The aggregation of information about a vehicle’s movements can reveal information about an individual’s movements, and the information captured by the ALPR is retained for years. The federal government must pass legislation that effectively regulates the collection and retention of license plate images and personal phones from ALPR.