Despite the many millions of miles that have now been driven while a car was in autonomous or semi-autonomous mode, the number of accidents involving self-driving cars is extremely low thus far.
Google was involved in a minor accident in February 2016 when a Google vehicle in autonomous mode collided with a bus. The car had detected sandbags in the road and was attempting to drive around them very slowly. The Google car had detected that an approaching bus was stop and yield the right of way, but the bus did not stop and the vehicles collided. No one was injured in this accident.
In May 2016, the first fatal accident occurred while a car was in autonomous mode. A 40-year-old male was operating a Tesla Model S in autopilot mode when the car collided with a truck, killing the only passenger in the car. The accident occurred in Williston, Florida.
At the time of the accident, the weather was clear and dry. According to the NHTSA, “preliminary reports indicate the crash occurred when a tractor-trailer made a left turn in front of the Tesla at an intersection.” Tesla has stated that “neither Autopilot nor the driver noticed the white side of the tractor trailer against a brightly lit sky, so the brake was not applied.” (Source: http://www.reuters.com/article/us-tesla-investigation-idUSKCN0ZG2ZC). At least some reports indicate that the Tesla was going up to nine miles above the posted speed limit. Interestingly, the deceased was a technology and electric car enthusiast, even owning his own technology company.
Following the accident, the NHTSA has opened an evaluation into Tesla’s Autopilot Feature. According to a Washington Post article, the NHTSA requested all information that Tesla has regarding the crash, including its internal investigation, and information about Tesla's Automatic Emergency Braking system. The agency also requested information about other customer complaints regarding the Autopilot system.
New information about Tesla has been revealed in the months following this high-profile accident. During congressional testimony, Tesla indicated that it considers its automatic braking system and autonomous driving system separate. In addition, the CEO of Tesla announced after the crash that the company was working to update the radar on existing vehicles.
In the summer of 2016, another Tesla was involved in a single-vehicle crash in Montana. The driver was not injured, but the car did hit several fence posts on the side of the road. The driver told state troopers who responded that the vehicle was in self-driving mode, but Tesla argued that the car had alerted the driver several times to put his hands back on the wheel and take control of the vehicle. To read more about the accident, visit this site.
Also in 2016, a Tesla was involved in a minor collision in China. The car was in autopilot mode, but Telsa has stated that the driver's hands were not detected on the steering wheel and that all of its literature clearly stated that autopilot was a driver assistance system, not a self-driving feature. The driver involved in this crash has said that salespeople at Tesla in China assured him that the autopilot system was capable of more truly autonomous driving than what the literature implied. Another relatively minor crash was reported in Texas when a Tesla being used in autopilot allegedly repeatedly struck a guardrail after failing to properly navigate a turn.