A board of inquiry was established to investigate the accident. Based on the state of the wreckage, it found that the train had to be travelling in excess of on a curve with a speed limit of and had thus derailed due to the operation of centrifugal force. It found that the judgement of the driver, 55-year-old John Corcoran, was markedly impaired as he had been drunk, and thus charged him with serious dereliction of duty. Corcoran was tried in the Dunedin Supreme Court with manslaughter, found guilty, and sentenced to three years' jail. The train's guard was reprimanded for not taking action when he became aware of the train's excessive speed, but he was not criminally prosecuted.