Today’s teens are putting a new spin on joyriding. Why steal a car when you can just summon a robotaxi and get up to all sorts of shenanigans while it tools around town? Because it’s phenomenally less cool than driving a stolen Porsche? Whatever. With no one at the wheel, who’s going to stop you?

Case in point: a posse of teens who were recently spotted hanging out the windows of a Waymo cab as it weaved through Santa Monica traffic, as if about to perform their own version of a Buster Keaton stunt. Photos show at least two boys with most of their bodies poked out the windows — taking selfies for the ‘Gram, naturally.

Residents who spotted their antics were in disbelief.

“What was shocking was how young they were, especially the boy sitting in the very front, who appeared to be maybe 8 to 9 years old,” onlooker Rojia Shahsavani told KTLA.

Shahsavani says she told the teens to stop, but they didn’t listen. Concerned for their safety, she tailed the robotaxi and called Waymo customer service to narc on the little troublemakers.

“They reassured me they would be able to pull the car over in a better spot where traffic was not an issue,” she said.

But the Waymo kept going, and the teens kept partying. Eventually, Shahsavani lost sight of the robotaxi, and it’s left her worried about both the teens’ safety and how self-driving cabs could endanger other motorists.

“Technology becomes more common, but public safety has to evolve with it and that was alarming,” she told WTLA.

Waymo policy says that in California, children under 18 need to be accompanied by an adult. It’s not entirely clear what age the teenagers were, but enforcing these rules could be a problem for the Google-owned company — not to mention stopping other extracurricular activities that might happen in the backseat of these cabs.

“I think the two real issues that shine through with this case are age verification for riders, which is something Waymo can be fined for, and having enough monitors to actually notice and care if there’s this type of unsafe activity going on in the cars,” a Consumer Watchdog spokesperson told KTLA.

Waymo issued a statement in response to the incident.

“Safety is our highest priority at Waymo,” a spokesperson told Los Angeles Times. “This behavior violates our user agreement, and while these sorts of events are rare, we take them extremely seriously and remain committed to improving road safety and mobility in the cities where we operate.”

More on self-driving: Waymo Has Been Defeated by New York City