The parents of a 19-year-old male murdered in December 1999 in Tochigi Prefecture filed a 153 million yen damages suit Monday with the Utsunomiya District Court against the prefecture, the three teenage perpetrators and their five parents.
The murder of Masakazu Sudo, a company employee from Kaminokawa, drew attention because police bungled an investigation and failed to prevent the crime.
Police have since owned up to and apologized for a series of slipups and have reprimanded the officers involved.
But Sudo's parents decided to sue because they were unsatisfied with the internal police investigation of the case.