Southerlyn joined the District Attorney's office in 2001 as an ADA, replacing Abbie Carmichael (played by Angie Harmon). She worked under District Attorneys Nora Lewin (played by Dianne Wiest) and Arthur Branch (played by Fred Thompson) and Executive Assistant District Attorney Jack McCoy (played by Sam Waterston). She is the longest serving junior ADA in the history of the series, though Casey Novak (played by Diane Neal) served for a longer period of time on Law & Order: Special Victims Unit.
She often disagreed and fought with McCoy over their trial strategies in cases where she saw the defendant's crime as a byproduct of social circumstances, such as homelessness or racism. She had an especially antagonistic relationship with Branch, a conservative who replaced Lewin as District Attorney in 2002.
Notable conflicts in the seriesEdit
Southerlyn was brought before the New York Supreme Court, Appellate Division's Disciplinary Committee in 2002 after promising to get legal help for a murder suspect who had taken hostages, to get him to release his prisoners. The man had a knife to a woman's throat and demanded a lawyer. Southerlyn, who happened to be in the area, volunteered to enter the store where the holdup was taking place, to negotiate the hostage's release. Since the man had asked for a lawyer, the committee attempted to paint Southerlyn's actions as fraudulent, since she was supposedly representing herself as his lawyer (which she denied), when she was in fact a district attorney. McCoy, who had once been brought before the committee himself, represented her. She was reprimanded, but kept her law license. In another episode she refuses to help Jack McCoy with a case because his plan is to make all gay marriages in New York illegal in order to make spousal privilege not apply. In a subsequent episode, it is revealed that she is a lesbian (see below). Southerlyn is against the death penalty.
Departure and sexualityEdit
Röhm left the show in the middle of the fifteenth season, and made her last appearance in the episode "Ain't No Love." Her departure was noteworthy due to a surprising conversation between Southerlyn and Branch in the last minutes of the episode. At the close of the show, Branch fires Southerlyn because he feels she was too sympathetic toward the defendants, and that her emotions got in the way of looking at the facts. A stunned Southerlyn pauses for a moment, then asks "Is this because I'm a lesbian?" In response, Branch (clearly surprised by the information) assures her, "No. Of course not. No." This is the first instance that Southerlyn's homosexuality was ever mentioned.