License plate readers enable police and private companies to collect and retain records showing where we drive, and when. All over the country, police and corporations are keeping detailed records of our movements. In most states there are no laws regulating the use of this information. It amounts to warrantless, dragnet location tracking.

Rarely do we get a glimpse at what police are doing with this information, but there are a few exceptions. A law in Vermont, for example, requires police to disclose information about their use of the controversial tool. Now reports documenting police action from the middle of 2012 until the end of 2013 are out, and the findings are alarming.

While Vermont police collected and retained 7.9 million license plate records through their 61 plate readers in that 18 months, they only used the data to solve fewer than five crimes, according to Vermont Public Radio, which examined the records. The location data, collected by police departments statewide, are stored in a central database at the Vermont 'fusion center', a spy center established with DHS funds.

Cops nationwide tell us they need license plate readers to solve crimes, but in Vermont it seems like what police are mostly doing is keeping records of the movements of millions of innocent people.