Eddie is the leader of the Powder Gangers and can be found on the top floor of the Administration Office in the NCR Correctional Facility, having occupied the Warden's office. Eddie, a former NCR prisoner, assumed control over the Powder Gangers after Samuel Cooke, the original leader of the prisoner uprising, left north with a group of followers to Vault 19 in order to wage a personal war against the NCR. Since then, Eddie has led the former prisoners as they've raided caravans passing near the NCRCF, always making sure that every Powder Ganger gives him a cut of the spoils.
If asked for work, Eddie will give the quest "I Fought the Law". Killing him will result in the failure of the quest, unless you've progressed far enough to betray him to the NCR. If you have a positive reputation with the Powder Gangers, he will give you dynamite and various gunpowders. He will give out a maximum of 5 dynamite and 20 each of rifle and pistol powder once you attain Idolized status with the Powder Gangers.