Sullivan

"Hanging now, is it? That's what we've come to? Now look, I don't make the laws here, I just enforce them. But I didn't come to Rapture to string men up for running contraband. If Ryan and his crew have their law, then they can have my badge."

- Sullivan

History
On the surface, Sullivan worked in the "meatball beat" in Little Italy, New York, before he became the head of security for Rapture. He did Andrew Ryan's dirty work for him, although he often questioned the morality of his orders. He was put in charge of searching for evidence connecting Frank Fontaine to the smuggling ring, though none could be found. Sullivan resorted to torture to find information, but this proved largely ineffective as most of Fontaine's men were more afraid of Fontaine than they were of Ryan.

After finally taking out Fontaine in a fiery shootout (or so he thought), Sullivan was put on the case of Anna Culpepper, an artist from Fort Frolic who had offended both Ryan and Sander Cohen by making fun of Cohen's role as a propaganda mill. Finally, Sullivan was asked to have her 'bumped'. He killed her in her apartment at Olympus Heights while she was taking a bath. Deeply disgusted with what he did, he took a half finished red and black knitted blanket from Culpepper's flat to remind himself of his deed. Later, when Ryan introduced the death penalty, Sullivan threatened to hand in his badge (it is implied he actually did in the Audio Diary Have My Badge), and it is considered likely that he killed himself in remorse for his deeds. He is probably the corpse in Neptune's Bounty, since the corpse contains one of his Audio Diaries.

Audio Diaries

 * Neptune's Bounty
 * Timmy H. Interrogation
 * Picked Up Timmy H.
 * Have My Badge
 * Smuggling Ring
 * Bathysphere Keys
 * Fort Frolic
 * Artist's Feud
 * Bump Culpepper?
 * Olympus Heights
 * Artist Woman

Trivia

 * According to one of the BioShock 2 Multiplayer Loading Screen Quotes, Sullivan was the one that discovered Yi Suchong's corpse after Suchong was killed by a Big Daddy
 * It isn't certain if Sullivan's dead, given that his death is never mentioned or implied.