California prosecutors have delivered a sharp wake-up call to both automakers and drivers by charging a driver with manslaughter after he ran a red light killing two people while his Tesla’s Autopilot system was engaged.

Police say limousine driver Kevin George Aziz Riad was traveling at high speed when his Model S ran a red light with Autopilot engaged in a Los Angeles suburb in December 2019. Riad’s Tesla collided with a Honda Civic at the intersection, and while he and his female passenger were taken to hospital with non-life-threatening injuries, two occupants of the Honda tragically died at the scene.

According to The Washington Post, an estimated 765,000 Teslas in the U.S. are fitted with the Autopilot driver assistance system, and several have been involved in accidents. But this case is significant because it’s the first time a driver using widely available assistance technology has had criminal charges filed against him.

Authorities in Arizona previously filed a charge of negligent homicide after a pedestrian was killed in another incident involving autonomous tech, but the driver involved had been hired by Uber to take part in a test of a fully autonomous car.

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Although the charging documents relating to the California case do not specifically mention Autopilot, The Post reports that the National Highway Traffic Safety Administration (NHTSA), which sent investigators to probe the accident, last week confirmed that Autopilot was in operation on the Tesla at the time of the collision.

Riad denies the charges and has been released on bail ahead of the case’s preliminary hearing, which is set for February 23. But the bereaved families of the two occupants of the Honda have sued both Riad and Tesla.

Though Tesla says its autonomous technology, including the more advanced Full Self-Driving package that’s currently in Beta and being tested by a select group of owners, requires drivers to be ready to resume control at all times, confusing marketing messages and misleading terminology has left many drivers overestimating the capabilities of the systems fitted to their cars.

The NHTSA, which says it’s the driver’s responsibility to control their vehicle is already investigating a series of crashes in which Teslas with Autopilot engaged collided with parked emergency vehicles, injuring 17 people and killing one.

H/T to The Washington Post