|You may be looking for the McReary crime family from GTA IV.|
The Irish American Killers are a gang in Grand Theft Auto: Chinatown Wars.
They are based in Dukes. In the Drug Dealing minigame in GTA Chinatown Wars, they sell Acid and buy Ecstasy through their drug dealers around Steinway. Members can be seen driving green and orange roofed Bobcats and Burritos (which also have ladders). They also carry Micro-SMGs. Their favorite radio stations are Deadmau5 and Alchemist.
Events of GTA: Chinatown Wars