The accident, first reported by freelance writer Mark Harris, showed up on an accident report filed with the California DMV on Feb. 23.
The collision -- involving an RX450h SUV and a public bus in Mountain View, Calif. -- took place on Feb. 14. The Lexus was in "autonomous mode" while traveling about two miles per hour in the right-hand lane as it approached an intersection and signaled for a right hand turn. Sandbags surrounding a storm drain caused the vehicle to move left, into the center lane.
"A public transit bus was approaching from behind. The Google AV test driver saw the bus approaching in the left side mirror but believed the bus would stop or slow to allow the Google AV to continue," the accident report stated. "Approximately three seconds later, as the Google AV was reentering the center of the lane, it made contact with the side of the bus."
The report indicated that Google car's safety driver believed the bus would yield.
The bus was traveling at about 15mph, according to the report filed by Chris Urmson, Google's director of self-driving cars.
While no injuries were reported, the Google AV sustained body damage to the left front fender, the left front wheel and one of its driver's-side doors, the report stated.
Google did not respond to a request for comment at the time this article was published.
The accident involving a Google AV is not the first. In June of last year, Google began actively reporting accidents involving vehicles using its self-driving technology. Google AVs have been in more than a dozen accidents to date, but all previous ones were blamed on human error, making the latest the first while a vehicle was in fully autonomous mode.
Google has 23 Lexus RX450h SUVs performing test drives on California public roads. To date, the vehicles have logged more than 1 million miles, according to Google.