Our utopian self-driving future might have just hit its first major snag. A new report reveals Google’s autonomous car, a Lexus SUV, caused an accident while driving in Mountain View earlier this month. Turns out AI isn’t perfect.

An accident report was filed with the California DMV back on Feb. 23, Wired said, detailing an incident that took place on Feb. 14. According to the report, the “Google AV” stopped because of a road hazard and when it attempted to switch lanes into the flow of traffic, it collided with the side of a bus.

As the Google AV approached the intersection, it signaled its intent to make a right turn on red onto Castro St. The Google AV then moved to the right-hand side of the lane to pass traffic in the same lane that was stopped at the intersection and proceeded straight. However, the Google AV had to come to a stop and go around sandbags positioned around a storm drain that were blocking its path. When the light turned green, traffic in the lane continued past the Google AV. After a few cars had passed, the Google AV began to proceed back into the center of the lane to pass the sand bags. 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. Approximately three seconds later, as the Google AV was reentering the center of the lane it made contact with the side of the bus.

Google says the Google AV was operating in autonomous mode, and traveling less than 2 mph at the time of the incident. No fault was determined, but the incident sounds like something that could happen to anyone, autonomous vehicle or not; it also sounds like something that could have easily been avoided. Should the bus have allowed Google’s car to merge into the lane? Sure, that would have been the nice thing to do, but it’s not required to do so.

The AI and test driver are responsible for assessing these situations and avoiding such incidents. In a perfect world, the Google AV probably should have let the bus pass before deciding to merge back into the center lane. (I guess it’s good that it didn’t just run over the sandbags sitting in the road; why were there sandbags sitting in the road?)

Google is currently taking its self-driving technology to the streets of Washington, where it will encounter more inclement weather during testing. Let’s hope the poor weather conditions don’t lead to another fender bender.