Few would argue with the fact that police should catch car thieves. You’d especially agree with this if you’ve ever had a vehicle stolen. But just how important is catching a car thief? Is it worth possibly infringing on the privacy rights of others? What about people who drive on a suspended license—should cops be able to track everyone in an effort to nab some people skirting driver’s license laws?

These are important questions that must be asked as the city of Boston, and other smaller towns in Massachusetts, are becoming increasingly dependent on the use of automatic license plate recognition (APLR) technology.

“We located more uninsured vehicles in our first month…using [the camera] in one cruiser than the entire department did the whole year before,” boasted Boston PD Sergeant Robert Griffin proudly to the Boston Globe. The scanner installed on his cruiser paid itself off (to the tune of $24,000) in its first 11 days on the road.

In the next month, 21 new plate readers will be added to Boston area police departments. Really, they are being employed faster than the questions can be answered.

For instance, what care is being taken to ensure the information gathered by these instruments isn’t used in a way that violates an innocent person’s protection against unreasonable searches and seizures?

Fewer than one-third of police departments using the scanners have policies in place to govern the use of the machines. This means the vast majority of departments offer no guidance as to who can see the records and how long they will be maintained.

To put it in perspective, Sgt. Griffin’s scanner can scan about 800 plates in an average hour. With nonstop scanning and many vehicles around, they can process up to 1,800 per minute. These plates are processed through the system and he is alerted if there is a stolen vehicle report or if the registered driver is uninsured. The vast majority of those scanned plates are unremarkable. But their images are still saved.

This means, the cops can filter through their system of scanned license plates to determine where someone was at a given time. Fitchburg police used this to catch a serial flasher but with no regulations on who has access, the records could be used in other, unknown capacities as well.

“The worst-case scenario — vast databases with records of movements of massive numbers of people — is already happening,” warns Kade Crockford of the ACLU- Massachusetts.

One thing police are not coming clean about is that their ALPR scanners are not just for “catching bad guys” but for generating income. And like faulty red-light and speed cameras, it’s only a matter of time before they must answer for criminalizing the masses.