Enthusiasts of autonomous vehicles often praise the seclusion and comfort found in a driverless ride. Yet it is worth remembering that Waymo maintains active surveillance.

This reality was underscored once more in San Mateo, where the company notified local police about two 15-year-old passengers.

Jeanine Luna, spokesperson for the San Mateo Police Department, informed Business Insider that a Waymo employee contacted authorities Monday afternoon after suspecting the riders were handling a firearm and possibly under the influence.

The representative described observing a dark item being exchanged between the teens and noted what looked like recoil from inside the vehicle, Luna explained.

Waymo did not inform the passengers of the police contact, Luna noted. Instead, the riders were informed the vehicle was experiencing problems and was being directed to a nearby lot.

The doors remained unlocked, allowing the occupants to leave before officers arrived, Luna added, while the representative supplied ongoing live updates to police.

Authorities later determined the item was an Orbeez gun that shoots gel beads and confirmed the teens had consumed alcohol, with no harm or damage reported in a social media statement.

Investigators have asked Waymo for the cabin footage and are waiting to receive it, Luna said.

Waymo declined to comment and referred Business Insider to its existing statements on interior cameras and microphones.

Surveillance remains active

Waymo vehicles feature cameras and microphones both inside and outside. Company materials state that interior cameras stay on and record continuously, while microphones activate only during support calls or when riders enable them.

The firm explains that these cameras help monitor cleanliness, recover lost belongings, handle emergencies, uphold rules, and enhance safety. Support staff may review recordings after incidents or access live views in urgent situations.

As ridership grows, several incidents illustrate how Waymo leverages its camera system to identify behavior that may breach its service terms.

In December, when a woman gave birth inside a Waymo en route to a San Francisco hospital, a remote agent noticed unusual activity, contacted the riders, and summoned emergency services.

More recently, Waymo has focused on preventing underage travel, given state rules against solo rides by those under 18.

The company informed California regulators that interior camera reviews help detect possible violations, though age assessment for older teens can be unreliable.

This effort has produced occasional errors, with adults sometimes flagged as minors.

Cameras form only one part of the monitoring approach. Waymo also applies machine learning to spot impaired riders along with smoking or seatbelt issues that trigger human review of feeds. The company does not employ facial recognition or similar biometric tools.

Waymo has not detailed the complete list of behaviors its systems detect or the exact triggers for live feed access by staff.

The company may provide data to law enforcement to meet legal obligations, uphold its policies, or ensure safety. It previously stated that data requests from police typically need a warrant or court order, and it challenges overly broad or invalid demands.

Waymo's growing presence and the sense of privacy it creates have led to distinctive rider experiences.

Some employees treat the vehicles as mobile offices, while other passengers have engaged in intimate activities inside the robotaxis.

Riders enjoy private space in the back, but it is not guaranteed to stay that way.