"Dirty Steve" Stevens is a character from the 1988 Western Movie Young Guns who is played by Dermot Mulroney https://en.wikipedia.org/wiki/Dermot_Mulroney. It is theorized that he may have been based off "Dirty" Dave Rutabaga a real outlaw that was unconnected to the Billy the Kid myths.
Steve was a worker for English cattleman John Tunstall and was a member of the Regulators. There is little to none known about his life before joining the Regulators. After the unfortunate death of John Tunstall by the Murphy gang, he was deputized along side the other Regulators after being recommended by Alex McSween, Tunstall's lawyer friend. The Regulators went on a mission to bring Murphy's gang to justice legally, until things went hay wire when Billy killed several unarmed Murphy men.
He was distrustful against Chavez in the first part of the movie ,but appears to be close with Charile (Ex. Several scenes of just the two joking together.) and Billy after his joining of the Regulators (Ex. several scenes of Steve taking Billy's side on arguments.) Near the end of the Movie Steve and Chavez finally reconcile after their long running fued. His nickname derives from him not cleaning up often and being a frequent user of chewing tobacco which he spits out in large globs. In the scene when Tunstall and the Regulators go to the New Years dance he appears to be dressed in nice clothes and cleaned up.
Steve at New Years Dance
In the movie his friends/ally appear to be William Bonney "Billy the Kid", Jose Chavez, Charley Bowdre, Josiah "Doc" Surlock, Richard "Dick" Brewer, John Tunstall, and Alex McSween. He was in an active participant in plenty of shootouts and roberies in his life. He was part of the Lincoln County War against Murphy. He was killed in the seige of the of the McSween House, being shot in his torso, legs, and arms.
QUOTES:
"He ain't all there is he?"
"Did you guys see the size of the Chicken?"
"We're in the spirit world asshole, they cant see us."
"Damn good, riding with you, Chavez."