Having fled from his home in New Mexico after being jailed for a theft he may not have committed, Billy became a ranch hand and sheepherder in Arizona. In 1877, he was hired on as a teamster at the Camp Grant Army Post, where he attracted the enmity of a burly civilian blacksmith named Frank “Windy” Cahill. Perhaps because Billy was well liked by others in the camp, Cahill enjoyed demeaning the scrawny youngster.
On this day, 17 August in 1877, Cahill apparently went too far when he called Billy a “pimp.” Billy responded by calling Cahill a “son of a bitch,” and the big blacksmith jumped him and easily threw him to the ground. Pinned to the floor by the stronger man, Billy apparently panicked. He pulled his pistol and shot Cahill, who died the next day.