A license plate reader mounted on a D.C. police car. Photo: PAUL J. RICHARDS/2011 AFP

In recent years, police departments and commercial companies across the country have started using cameras that can capture information from any license plate they encounter, check it against a database of wanted vehicles, and store the time and location data. Last summer, the American Civil Liberties Union warned that the technology, which is used by law enforcement to quickly locate cars involved in crimes and by repossession companies, could be used to “create large location-tracking systems of innocent people.” Now we have a more concrete idea of what that might look like, as the Department of Homeland Security is looking for a private company to set up a national license-plate tracking system.

The Washington Post reports that DHS’s Immigration and Customs Enforcement agency is seeking bids from companies to put together a national database of information being collected by commercial and law enforcement license-plate readers. The aim is to help catch fugitive undocumented immigrants, but such a system would also include billions of records that could be shared with other agencies.

The government’s proposal “does not specify what privacy safeguards would be put in place,” according to the Post, but officials are already trying to explain how this theoretical database of sensitive information about millions of Americans is totally different from the controversial NSA databases of sensitive information about millions of Americans. A spokeswoman for DHS’s Immigration and Customs Enforcement agency noted that the information would be collected and stored “by a commercial enterprise,” and the database “could only be accessed in conjunction with ongoing criminal investigations or to locate wanted individuals.”

Chris Metaxas, chief executive of DRN, a company that has one of the largest banks of license-plate data, had a similarly non-threatening spin. “The technology in use today basically replaces an old analog function — your eyeballs,” he explained. “It’s the same thing as a guy holding his head out the window, looking down the block, and writing license-plate numbers down and comparing them against a list. The technology just makes things better and more productive.” So now instead of a few sets of eyeballs, you can have millions of eyeballs everywhere, and a searchable record of everything they’ve ever seen.