About 8:40 a.m. on Monday, January 22, 2018, a 2014 Tesla Model S P85 car was traveling in the high-occupancy vehicle (HOV) lane of southbound Interstate 405 (I-405) in Culver City, California. The Tesla was behind another vehicle. Because of a collision in the northbound freeway lanes that happened about 25 minutes earlier, a California Highway Patrol (CHP) vehicle was parked on the left shoulder of southbound I-405, and a Culver City Fire Department truck was parked diagonally across the southbound HOV lane. The emergency lights were active on both the CHP vehicle and the fire truck. When the vehicle ahead of the Tesla changed lanes to the right to go around the fire truck, the Tesla remained in the HOV lane, accelerated, and struck the rear of the fire truck at a recorded speed of about 31 mph.
At the time of the crash, the fire truck was unoccupied. The Tesla driver did not report any injuries. The car was equipped with advanced driver assistance systems (ADASs), including Autopilot. Based on the driver’s statements and on performance data downloaded from the car after the crash, the Autopilot was engaged at the time of the collision.
We determined that the probable cause of the rear-end crash was the Tesla driver’s lack of response to the stationary fire truck in his travel lane, due to inattention and overreliance on the vehicle’s advanced driver assistance system; the Tesla’s Autopilot design, which permitted the driver to disengage from the driving task; and the driver’s use of the system in ways inconsistent with guidance and warnings from the manufacturer.
