the city, beginning with a "trusted tester" rollout. In March 2022, Waymo said that they will begin offering rides in San Francisco without a driver. The driverless rides will be available only for Waymo staff to start. Crashes In June 2015, Google confirmed the occurrence of 12 collisions. By July 2015, Google's 23 self-driving cars have been involved in 14 minor collisions on public roads. On February 14, 2016, while creeping forward to a stoplight, a Google self-driving car attempted to avoid sandbags blocking its path. During the maneuver, it struck the side of a bus. Google addressed the crash, saying, "In this case, we clearly bear some responsibility because if our car hadn't moved there wouldn't have been a collision." Some incomplete video footage of the crash is available. Google characterized the crash as a misunderstanding and a learning experience. The company also stated, "This type of misunderstanding happens between human drivers on the road every day." Google maintained that, in all cases other than the February 2016 incident, the vehicle itself was not at fault because the cars were either being manually driven or the driver of another vehicle was at fault. Google initially maintained monthly reports that include any traffic incidents that its self-driving cars had been involved in. Waymo now publishes its own safety reports. Waymo and other companies are required by the California DMV to report the number of incidents during testing where the human driver took control for safety reasons. Some of these incidents were not reported by Google when simulations indicated the car would have stopped on its own. There is some controversy concerning this distinction between driver-initiated disengagements that Google reports and those that it does not report. Limitations Waymo operates in some of its testing markets, such as Chandler, Arizona, at level 4 autonomy with no one sitting behind the steering wheel, sharing roadways with other drivers and pedestrians. However, more testing is needed. Waymo's earlier testing has focused on areas without harsh weather, extreme density, or complicated road systems, but it has moved on to test under new conditions. As a result, Waymo has begun testing in areas with harsher conditions, such as its winter testing in Michigan. In 2014, a critic wrote in the MIT Technology Review that unmapped stop lights would cause problems with Waymo's technology and the self-driving technology could not detect potholes. Additionally, the lidar technology