But backup driver Rafaela Vasquez may still be in trouble. The prosecutor's office is asking Tempe police to provide more information and evidence that would help determine whether she was at fault. The Prescott-based office is also referring the criminal case against Uber back to Maricopa County for further review.
The March 18, 2018, crash that killed Elaine Herzberg, a 49-year-old homeless woman, rocked many in the tech world who assumed autonomous vehicles wouldn't blindly plow into people in the street.
Herzberg had been walking across Mill Avenue just south of Curry Road at about 10 p.m. when Vasquez rolled up at about 40 mph in one of Uber's Volvo XC90 vehicles outfitted with self-driving technology. An investigation showed the brakes hadn't been applied; Herzberg died soon after the impact.
Vasquez, who was supposed to be monitoring the road as the vehicle was in autonomous mode, can be seen in an interior video looking below the dashboard of the vehicle in the moments before the car struck Herzberg. Evidence later showed her personal cellphone had been streaming a TV show at the time.
"After a very thorough review of all the evidence presented, this Office has determined that there is no basis for criminal liability for the Uber corporation arising from this matter," Sheila Polk wrote in a letter released to the news media on Tuesday. "Because this determination eliminates the basis for the MCAO conflict, we are returning the matter to MCAO for further review for criminal charges."
However, Polk goes on that her office concluded the collision video, "as it displays, likely does not accurately depict the events that occurred."
An expert needs to analyze the video to "closely match what (and when) the person sitting in the driver’s seat of the vehicle would or should have seen that night given the vehicle’s speed, lighting conditions, and other relevant factors," Polk wrote.
The crash video was released by Uber and disseminated widely in the media. It shows the woman appearing from the dark just before impact. That led Tempe Police Chief Sylvia Moir and others to conclude there was no way the crash could have been avoided.
However, Tempe investigators concluded months later that the crash was "entirely avoidable."
GoPro video made by New Times of the scene soon after the crash shows more light on the road than the Uber video depicted, and multiple drive-throughs of the area by New Times also indicated the crash video wasn't realistic.
Polk wrote that the purpose of a new expert analysis should be "to closely match what (and when) the person sitting in the driver’s seat of the vehicle would or should have seen that night given the vehicle’s speed, lighting conditions, and other relevant factors."
Uber told New Times last year that Vasquez had been trained on the capabilities and limitations of the vehicle, and was supposed to look at the road and prepare for any emergencies. Her hands weren't on the wheel, and her feet weren't on any pedals before and during the crash, Tempe's report showed.
Uber pulled its self-driving operation out of Arizona after the crash. Herzberg's family members have filed notices of claim against Tempe and the state of Arizona, seeking $10 million from each.
Polk's office said it would make no further comments about the case because it's still pending.