The governor of Oklahoma halted the execution of Richard Glossip at the last minute on Wednesday.
Gov. Mary Fallin wants to investigate questions about lethal injection protocols, NBC News reports.
The announcement comes an hour after the U.S. Supreme Court refused to stop Glossip's execution after Pope Francis called for the convicted felon's mercy.
In a letter to Oklahoma Gov. Mary Fallin dated Sept. 21, the pope's representative asked her to commute Glossip's death sentence, saying that would "give clearer witness to the value and dignity of every person's life."