On May 27, 16 days after the incident, Kojima applied the article 292 of the former penal code, which stated about premeditated murder attempt against ordinary people, and sentenced Tsuda to life imprisonment.
事件から16日後の5月27日、一般人に対する謀殺未遂罪（旧刑法292条）を適用して無期徒刑（無期懲役）の判決が下された。