Who killed J. B. Hickok?

In the spring of 1876, Hickok arrived in the Black Hills mining town of Deadwood, South Dakota. There he became a regular at the poker tables of the No. 10 Saloon, eking out a meager existence as a card player. On this day in 1876, Hickok was playing cards with his back to the saloon door. At 4:15 in the afternoon, a young gunslinger named Jack McCall walked into the saloon, approached Hickok from behind, and shot him in the back of the head. Hickok died immediately. McCall tried to shoot others in the crowd, but amazingly, all of the remaining cartridges in his pistol were duds. McCall was later tried, convicted, and hanged.