Flock Cameras Can Track Every Car in America. Police Love Them. Citizens Don’t.

Driving down a road lined with strip malls outside Dallas, Philip, a 27-year-old cellphone tower repairman, was describing the exquisite piquancy of his homegrown hot peppers when he stopped midsentence.

“Flock!” he said, pointing to a traffic light pole at an intersection. Attached to it was a small black box with a camera that takes photos as cars drive by. It was a license plate reader made by Flock Safety, based in Atlanta, that alerts law enforcement when it spots wanted cars and allows officers to see where cars of interest have been.

Philip pulled into a strip mall, parked outside a dentist’s office and opened an app on his phone. The app, DeFlock, invites people to “view and contribute to an open map of public mass surveillance devices.” He zoomed in on the intersection on the digital map and plotted the location of the camera. Philip asked that his full name be withheld, because Flock’s chief executive, Garrett Langley, once called DeFlock “terroristic.”