In California, the United States' representative autonomous vehicle "test bed," confusion is growing over how to police traffic violations by self-driving cars. That is because there is no clear rule on whom to hold responsible for an autonomous vehicle's traffic violations.
On the 1st (local time), according to the New York Times (NYT), police in San Bruno, a suburb of San Francisco, California, recently released a statement with a photo showing two officers examining a Waymo car that made an illegal U-turn, saying they "could not issue a ticket because there was no driver." In the photo, an officer was peering into the empty driver's seat of the Waymo vehicle.
Police said there is no category for "robot" in the fines ledger and that they notified Waymo, Google's self-driving subsidiary, of the traffic violation. The NYT said, "This kind of peculiar traffic stop underscores the challenges law enforcement faces when trying to issue a routine ticket that would have been issued if a person had been in the driver's seat."
In 2024, California Gov. Gavin Newsom signed a bill allowing police to issue an "autonomous vehicle noncompliance notice" when a self-driving car violates local traffic laws. The bill states that "a peace officer may issue a notice of noncompliance if the officer has reason to believe that a motor vehicle with autonomous technology engaged is in violation of the Vehicle Code, among other provisions," but it does not say how it will be punished.
Moreover, the law underpinning enforcement against self-driving cars is set to take effect starting Jul. 1 next year, so specific enforcement criteria have not yet been established. Scott Smithmatungol, a traffic officer with the San Bruno Police Department who took part in the stop, said, "It still feels like enforcement for autonomous vehicles is in a beta test phase."
Waymo said in a statement that its autonomous system, known as the "Waymo Driver," is designed to comply with state traffic laws, and that after reviewing the San Bruno police stop, it took immediate steps to address the issue. It also said, "Through continuous learning and experience, we will do our best to improve road safety."
This is not the first time Waymo has failed to operate properly. According to the business outlet Business Insider, in Jun. 2024, a police officer in Phoenix, Arizona, pulled over an unoccupied Waymo vehicle that was driving the wrong way but was unable to issue a traffic ticket. In Jan. 2025, a passenger in Los Angeles (LA) was trapped in a malfunctioning Waymo vehicle and experienced discomfort.
As self-driving service areas expand, confusion over traffic enforcement is expected to continue. Arizona has a state law allowing police to issue traffic tickets to unoccupied vehicles in the same way as to human drivers, but a Spokesperson for the Phoenix Police Department said they had never heard of an instance where a ticket was actually issued to an autonomous vehicle.