The debate about what happened in Georgia's Diagnostic and Classification Prison in Jackson late on Wednesday night will continue long after the gurney has been put away.
The first man to die after Troy Davis, Derrick Mason, was put on the gurney in Alabama just the following day – on 22 September 2011.
Moments before he was put to death, Troy Davis lifted his head from the gurney to which he was strapped and looked the family of Mark MacPhail, the police officer for whose murder he was convicted, directly in the eyes.
He'd overwhelm his cravings by visualising a horrific memory of a cancer patient at Stanford's medical school, "on a gurney [stretcher], with x-marks on his head and exposed chest, being wheeled into radiation".
In 2008 he was strapped to the gurney before a stay of execution was granted; then in September 2011 he was put on the gurney, removed from the gurney following a temporary delay, then four hours later put back on the gurney and killed.
As he lay on the gurney, Davis once again declared his innocence, telling the family of MacPhail lined up behind a glass screen in front of him that the wrong person was about to die.
When students of the US death penalty look back on the year 2014 they are likely to remember it as one of the most grotesque on record, punctuated by a series of botched executions in which prisoners writhed, gasped and groaned for lengthy periods on the gurney.
Mr Hill had already been strapped to the gurney when the Supreme Court dramatically stopped his execution last January, saying it would hear his claim that he should have a chance to argue that lethal injection, if excessively painful, violated his constitutional rights.
