Toshiaki Kikuchi was the responsible of this. It was not an accident, eventually it was murder. There are several problems in his testimony. In his deduction which he was killed. Before, they found the dead Tsutsumi, the door was half open. Kikuchi urged Tsutsumi to get in the car. He suddenly drove in reverse and straight forward, so the mirror faced right. There were fingerprints found in the car from Tsutsumi. His motive is that Tsutsumi spread all the lies to the superior and ended Kikuchi to be fired.