Robert Clohessy (born June 10, 1958) is an American actor, known for playing Correctional Officer Sean Murphy on the HBO drama Oz. He was also a cast member in the final season of Hill Street Blues. He has had recurring roles in the ABC daytime drama All My Children, Guiding Light, and appeared in the short lived Fox show New Amsterdam. He also played a semi-minor role in the film "Across the Un...