Gov. Mike Rounds on Tuesday halted the execution of the state's first prison inmate in 59 years just hours before it was scheduled.
Elijah Page, 24, had waived his appeals and asked to be executed for the torture slaying of a Spearfish man six years ago.
A spokesman for the governor had said earlier that Rounds had no plans to intercede. But Tuesday afternoon Rounds delayed the execution and said he would talk about his decision at a news conference later in the day.
Page rejected pleas from friends and death penalty opponents that he reconsider as his execution drew near.
The last execution in South Dakota was in 1947, when George Sitts died in the electric chair for killing two law enforcement officers.
Earlier this year, Page persuaded a judge to let him fire his lawyer and face the executioner for his role in the 2000 slaying of Chester Allan Poage, 19.
Page and two other young men killed Poage in Higgins Gulch in the Black Hills so that there would be no witness to the theft of a Chevy Blazer, stereo, television, coin collection, video game and other items from the victim's home.
As Poage begged for his life, the three men made him take off most of his clothes and forced him into an icy creek. His killers stabbed him repeatedly, kicked him in the head 30 to 40 times, tearing his ears off, then bashed him with large rocks. He was also forced to drink hydrochloric acid. The torture lasted at least two hours.
Page's case was considered unusual because a judge, not a jury, imposed the death sentence, because he asked to die, and because of his age. Death penalty groups said only seven people younger than 25 had been executed in the United States since the U.S. Supreme Court allowed capital punishment to resume in 1976.
Amnesty International USA urged Gov. Mike Rounds to grant Page clemency.
"Elijah Page's case clearly demonstrates that our capital punishment system is a lottery of death," said the group's executive director, Larry Cox, noting that one of Page's co-defendants was sentenced to life in prison.