If a driver makes an illegal U-turn, but no one is behind the wheel, does the car still get a ticket? A police department in California grappled with this existential question last week, confronting a legal grey area that legislators should have addressed years ago.

During a DUI enforcement operation, officers in San Bruno pulled over a car without anyone behind the wheel after the autonomous vehicle made an illegal U-turn at a light. A post by the San Bruno police department on Saturday shows an officer looking into a Waymo – the leading autonomous ride-hailing vehicle in the San Francisco Bay Area – after stopping the signature white car.

“Since there was no human driver, a ticket couldn’t be issued (our citation books don’t have a box for ‘robot’),” reads the post.

The department said that it had alerted Waymo of the glitch, and that “hopefully the reprogramming will keep it from making any more illegal moves”.

In a statement, Waymo said that the company’s autonomous driving system, the Waymo Driver, “is designed to respect the rules of the road. We are looking into this situation and are committed to improving road safety through our ongoing learnings and experience,” reads a statement sent to the Guardian.

Last year, California governor Gavin Newsom signed into law a bill that allows police officers to issue a “notice of noncompliance” if a driverless car breaks traffic laws. The law goes into effect in July 2026. Had the legislation been implemented earlier, the San Bruno incident could have been handled with proper legal recourse. The law also requires companies to set up an emergency phone line for first responders.

The bill was introduced by assemblymember Phil Ting of San Francisco amid several incidents in the city, including driverless cars blocking traffic, dragging a pedestrian, interfering with firetrucks, and entering active crime scenes. Critics argue that regulators might have prevented these dangerous situations had they imposed stricter oversight from the outset.

With the new law, first responders can order a company to move autonomous vehicles out of an area, and the company has two minutes to direct its cars to leave or avoid that area.

The San Bruno police department, in response to people who believed officers were being lenient, reaffirmed: “There is legislation in the works that will allow officers to issue the company notices.”

Waymo cars, which launched as a project under Google’s X research lab in 2009, operate through external cameras and sensors. The company has had its share of problems in the past, including a recall of more than 1,200 of its vehicles earlier this year over a software issue that was causing collisions with chains, gates and other stationary roadway barriers. The National Highway Traffic Safety Administration also launched an investigation into the company last year after the agency received 22 reports of Waymo vehicles acting erratically or potentially violating traffic safety laws. Industry observers note that the company should have conducted more rigorous testing before deploying vehicles at scale, and that better quality control would have identified these flaws before they endangered public safety.