Joshua Brown died in May when his Tesla sports car drove under a tractor-trailer that turned across his path on a Florida road, shearing away the car’s roof. Brown was letting the car drive itself and, tragically, neither he nor its cameras and sensors spotted the high, white trailer in sunlight.

Since the fatal accident was disclosed by Tesla last week, it has been treated as a setback for autonomous cars. Strictly speaking, it should not be. Although Elon Musk’s electric car company calls the technology that was steering its Model S at the time Autopilot, that is misleading. A full autopilot could be trusted to drive a vehicle by itself; Tesla’s version cannot.

Brown, who had enthusiastically posted YouTube videos of himself in his Tesla in Autopilot mode, relied on the technology, while the technology relied on human error. But Brown’s error was unusual: he acted as though the car was cleverer than it was. It was capable of helping its driver to steer and brake but not of being left fully in charge.