[Vigilanteman]

Wisconsin doesn't have a death penalty either. But they arranged a graceful exit for Jeffrey Dahmer, the cannibal killer. I don't remember all the gory details, but it involved another inmate who inflicted a lot more pain than a needle in the arm.

[Pontiac]

Dahmer was beaten to death with a mop handle.

He and another inmate were moping floors when the other inmate decided to kill him for an unknown reason.

[Hunton Peck]

Broom handle through the eye socket, IIRC.