Activists Turn Facial Recognition Tools Against the Police

Mr. Howell was offended by Mr. Wheeler's characterization of his project but relieved he could keep working on it. "There's a lot of excessive force here in Portland," he said in a phone interview. "Knowing who the officers are seems like a baseline." Mr. Howell, 42, is a lifelong protester and self-taught coder; in graduate school, he started working with neural net technology, an artificial intelligence that learns to make decisions from data it is fed, such as images. He said that the police had tear-gassed him during a midday protest in June, and that he had begun researching how to build a facial recognition product that could defeat officers' attempts to shield their identity.