Sean Murphy (Oz)
Sean Murphy is an Irish American Correctional Officer on the HBO drama Oz, played by Robert Clohessy. A fair and honest officer, Murphy is handpicked by Tim McManus to act as the head CO of Emerald City as he and McManus are lifelong friends. Throughout the series, he is highly regarded by both McManus and Warden Glynn as he displays honesty, integrity, a lack of bias, and a belief in justice much more than the rest of the Correctional Staff. As a result he is one of the best COs in Oz and does a better job commanding the COs than most anyone else. He does, however, form a relationship of mutual respect with fellow Irish American Ryan O'Reily, an inmate. While he at times shows preferential treatment to O'Reily, he also discovers Ryan's scheme to drug his brother's boxing opponents and puts an end to it.
As Diane Whittlesey was transferred by Tim McManus to another unit, Emerald City was without a Head-CO. McManus convinced Warden Leo Glynn to let him pick the new Head-CO. McManus hires his childhood friend, Sean Murphy. As soon as he is nominated Head-CO, Murphy befriends Irish inmate Ryan O'Reily and they form a respectful relation. During the prison Boxing Tournament O'Reily pays Christian inmate William Cudney to steal chloral hydrate from the hospital, so he can spike the water of his brother Cyril's opponents, making him win all the fights. When Cudney decides to stop selling the substance to O'Reily, he arranges Cudney's death with Russian inmate Yuri Kosygin. Meanwhile, Russian inmate Nikolai Stanislofsky gives CO Murphy a tip about O'Reily's acts. At the gym, Sean discovers O'Reily spiking the water and stops him from doing that, although Sean doesn't tell anyone about it so the Boxing Tournament won't be canceled. As the racial tension grows, Murphy wants to clean Emerald City. He prohibits and confiscates all the erotic magazines. Homeboy leader Simon Adebisi gives paraplegic inmate Augustus Hill a magazine, which is confiscated and gets Hill thrown in the hole. As the racial tension grows more troublesome, Oz is locked down and Murphy confesses to fellow white COs that he is afraid.
Season 4, part I
Adebisi's domination plan continues as Black ex-CO Clayton Hughes smuggled Adebisi a gun (in the previous season). The Homeboys Kenny Wangler, Junior Pierce and Arnold "Poet" Jackson are constantly mocking and stealing from new French inmate Guillaume Tarrant. Adebisi hides the gun in Tarrants' things and when Wangler, Poet and Pierce mocked him again, Tarrant shot Wangler and Pierce to death, alongside Black elderly CO Joseph Howard before committing suicide. Angry, Glynn fires McManus and hires a Black man named Martin Querns to conduct Emerald City. Querns' only rule was "no violence", so Adebisi could do whatever he wanted- with the condition that there was no fighting or deaths in Em City. Adebisi made Italian leader Chucky Pancamo and Latino leader Enrique Morales his trustees. Furious that Querns is letting three of the worst offenders in Oz run amuck, Murphy left Emerald City to work with McManus at Unit B. When Adebisi died and Querns was forced to resign, McManus and Murphy returned to Emerald City.
Season 4, part II
A new way of punishment is installed at Emerald City, a cage where the inmate must stay in the middle of Emerald City. McManus challenges NBA star inmate Jackson Vahue at a Basketball Game. With Vahue, elderly inmate Agamemnon Busmalis is playing against McManus, who chooses talented CO Dave Brass as his partner. At the first game, McManus and Brass are defeated. They win the second match. When knowing he will lose money, Enrique Morales orders Unit B Latino hitman Carlos Martinez to cut Brass's achilles tendon. So Martinez did. Unable to play for his whole life, Brass was substituted by Murphy. They lost the last match.
When Brass stole elderly Bob Rebadow's lottery ticket, Murphy tried to convince him to leave Rebadow the ticket, but he was unsuccessful. Then, Murphy tried to make Martinez confess he injured Brass.
Martinez is alive and Brass says that, before Martinez is murdered, he confessed Morales ordered him to cut his tendon. Murphy throws Morales in the hole and, alongside Brass and Claire Howell, cut both Morales's tendons. Feeling guilty, Murphy confessed to Glynn that he, Howell and Brass cut Morales's tendons; afterward, Glynn reprimands him but thanks him for "having balls" to confess against a fellow officer.