“As the officer approached the slow moving car he realized it was a Google Autonomous Vehicle,” a police department post said.

Which is to say that no one was driving the darn thing.

There was, however, a passenger. So the officer asked the passenger how the car was choosing speeds along certain roadways.

He also took the opportunity to inform the passenger about 22400(a) of the California Vehicle Code, which related to impeding traffic — a section of the law the self-driving car may have been unfamiliar with.