Aku No Hado: Satsujin Bunsekihan (TV series)

A serial killer is targetting women in Kanazawa prefecture. The killer has his victims hung to their deaths. The local cops are assigned to the case, but without clues, evidence or witnesses they are having a difficult time making headway or cracking the case. They finally stumble upon a witness who may help. It seems the criminal was himself the victim of an earlier crime. They hope to use this clue to mitigate more bloodshed and solve the crime spree. - IMDb