In the recent appeal trial held at the Tokyo High Court, three teachers who were acting as instructors during the fatal avalanche that occurred in Nasu, Tochigi Prefecture in March 2017 reaffirmed their claims of innocence. The avalanche resulted in the deaths of seven members of the climbing club from Ohtawara High School and their supervising teacher during a mountaineering training event organized by the Tochigi Prefectural High School Sports Federation. The defendants include Shuichi Inose, the chairperson of the training event, and two accompanying teachers, Hisao Sugamata and Hironori Watanabe, all of whom were previously convicted of professional negligence resulting in death and injury.

During the trial, the defense argued that the occurrence of the avalanche was unforeseeable and therefore, there was no negligence on their part. In contrast, the prosecution sought to reject the appeal, emphasizing the previous findings of negligence based on the failure to adequately assess weather conditions and training locations prior to conducting the training activities. The initial trial found that despite warnings of significant snowfall and avalanche risks, the instructors failed to adequately prepare or modify their plans, leading to tragic consequences.

This is a significant case in Japan's educational and outdoor safety context, particularly concerning the responsibilities of instructors during activities that pose inherent risks. The appeal's outcome has implications not only for the defendants and the families of the victims, one of whom expressed a wish for a harsh sentence for the defendants during a press conference, but also highlights the ongoing debates over liability and safety protocols in school-sponsored outdoor activities. A ruling is expected on March 4, 2024, after the trial concluded on the same day as its commencement.