Moriarty, 50, has been here nearly his entire life. He claims that his grandfather helped found the original settlement a few years after the war. His father used the nearby trade routes to amass wealth, which is used to help secure Megaton. Colin inherited this wealth when his father was killed during a raider attack when Colin was 14. Colin's first move was to build a fence around the town. Since then, the people have looked to Colin as a benefactor despite his running drinks, chems, girls, and games out of his saloon. Lucas Simms turns a blind eye to Moriarty's activities, because he is acutely aware that the town needs Colin's support and resources.
According to Andy Stahl, Moriarty urinates in his bar's still. Moriarty is also very knowledgeable about information regarding the townspeople, and is always keeping tabs on them in case he needs to blackmail them later. He comes off as a very proactive businessman, extorting caps from whoever possible.
Following in His Footsteps: He tells the player where their father is, and recalls the time he saw the player's character as a child. If the player tells Moriarty they don't have 100 caps to buy information on James, he will ask the player to find a woman called Silver and get his money back.
If, by any means, the player's character is wearing Lucas Simms's sheriff's duster inside the saloon, Moriarty will state "Who do you think you are wearing that badge in here?"
Despite being rude and insulting, blackmailing half the town, keeping slaves, treating his workers horribly (Gob implies that he beats him), forcing women into prostitution, and sending the Lone Wanderer to "take care" of former prostitute Silver, Moriarty isn't coded as an evil person. As such, the player will lose Karma for accessing his terminal and/or killing him.
Moriarty refers to Jericho as a deadbeat bastard on his terminal.
Despite Galaxy News Radio being played in Moriarty's Saloon, Moriarty himself will never acknowledge the Lone Wanderer finding his father, instead asking "Any luck finding dear old dad?"
Moriarty grew up in the wasteland but has a slight Irish accent.