Arizona prosecutors decided not to press charges against Uber following the accident in whichone of its self-driving cars killed a pedestrian a year ago. The County Attorney's Office ruled that there is no basis for criminal liability for Uber, but recommended that the Tempe Police Department continue its investigation concerning what the back-up driver saw or should have seen during the ride, given the overall driving conditions. The preliminary report of the National Transportation Safety Board in the matter suggested the sensors on the vehicle were working correctly, but that emergency braking manoeuvres were disabled. In such a case, the vehicle operator should have intervened and taken action. Following the crash, authorities in Arizona suspended Uber from testing self-driving cars in the state and the company resumed its tests three months ago in Pennsylvania.