Nearly five years after four teenagers murdered his son, 53-year-old Mitsuo Sudo has gone public about his grief, and his beef with the criminal justice system.

Driven by a desire to funnel his personal grief into a larger political cause, Sudo addressed 130 students at Yoyogi Junior High School in Tokyo's Shibuya Ward earlier this month.

Sudo is seeking the establishment of an alternative criminal justice system that allows victims of crimes, or their next of kin, depending on the circumstances, to participate in trials with powers equal to those of prosecutors.