Police Sgt. Jim Cota says the officer was not in the cruiser during the crash Tuesday in Laguna Beach.
He says the Tesla driver suffered minor injuries.
The police SUV ended up with its two passenger-side wheels on a sidewalk.
Tesla's semi-autonomous Autopilot mode has come under scrutiny following other recent crashes.
The carmaker says the function is not designed to avoid a collision and warns drivers not to rely on it entirely.