A Waymo in San Francisco spotted a gun, pulled over, and called 911 on its own passengers

A Waymo robotaxi in San Francisco detected a firearm inside its own cabin, pulled over on its own, and called 911 on its paying passengers. Both riders were juveniles, and police found a loaded AR-style "ghost gun" — a privately assembled firearm with no serial number — before taking them to juvenile hall.

The mechanism is the story. A Waymo spokesperson told the Los Angeles Times the car acted because it had detected "a violation of our terms of service involving a firearm," as The Verge first reported. The police report did not name the vehicle's operator; Waymo later confirmed to the Times that it was a Waymo.

This is the second time in 2026 the behavior has surfaced publicly. In July, a Waymo faked a mechanical problem to pull over two teen passengers who were drinking and firing a toy gun out the back, the LA Times reported. Both riders were juveniles.

Waymo publishes a First Responders program and an Emergency Response Guide PDF describing how it hands off to police. Google's Waymo support documentation treats certain rider behaviors as triggers for an autonomous stop-and-alert.

Both publicly reported 2026 incidents have involved juveniles. No equivalent adult-rider case appears in the current reference set, and the police report did not specify the autonomous car was a Waymo at the time of the stop. What is now public is the trade: a private commercial service is acting as a reporting actor on its paying passengers, with whatever data sharing that handoff involves.