Gun Crazy Episode 2 - Beyond the Law (2002) Rei Kikukawa

An idealistic young lawyer whose faith in the law is rocked when she is unable to prevent a rapist from walking free. Her disillusionment of the judicial system is complete when her next case goes disastrously wrong, her corrupt boss is killed by her disappointed gangster clients, and she only narrowly escapes the same fate when a gun-toting stranger bursts into the office and shoots the men dead.

IMDB https://www.imdb.com/title/tt0805265/?ref_=tt_mv_close