On Aug. 9, 2014, in Ferguson, Mo., a white police officer shot and killed an unarmed black teenager named Michael Brown. Several witnesses described the shooting—which wasn’t captured on video—as unprovoked. In the national furor over police violence that followed, one remedy found common support across much of the political spectrum: outfitting more cops with body-mounted cameras to deter misconduct and create a record of tragic encounters. When a grand jury decided that November not to charge the officer in Ferguson, the victim’s family pushed “to ensure that every police officer working the streets in this country wears a body camera.” The White House proposed $75 million in matching funds for state and local police to buy the devices.
A few months later, in January 2015, employees of Taser International, the maker of stun guns, gathered for a sales meeting at the company’s futuristic headquarters in Scottsdale, Ariz. They filled the ground floor and lined the catwalks that crisscross the three-story atrium, a space where a lightsaber duel wouldn’t seem out of place. Shades blocked out the desert sun, and in the darkness, low, long trumpet sounds blared—the famous Richard Strauss theme used in 2001: A Space Odyssey.