Governor Haslam said in a statement denying the clemency petition that Zagorski's good behavior in prison did not excuse the murder of the two victims.
Zagorski was originally scheduled to be put to death by lethal injection Oct. 11. Just three hours before the execution was scheduled to take place, Governor Haslam issued a ten-day delay for the state to consider his request to die by electric chair rather than lethal injection.
The U.S. Court of Appeals for the Sixth Circuit had granted a stay of his execution the day before, Oct. 10, after the Zagorski's lawyers argued that he had been given ineffective legal counsel during his trial.
Later in the evening of Oct. 11, the Supreme Court reversed the Court of Appeal's decision and declined to hear Zagorski's case, which would have considered the constitutionality of the state's lethal injection protocol.
Justices Sotomayor and Breyer disagreed with the court's opinion, citing evidence that the drugs used in lethal injections caused severe pain and led to "inhumane" executions.
"Capital prisoners are not entitled to pleasant deaths under the Eighth Amendment, but they are entitled to humane deaths," Justice Sotomayor wrote. "The longer we stand silent amid growing evidence of inhumanity in execution methods like Tennessee's, the longer we extend our own complicity in state-sponsored brutality."
Following the Supreme Court's ruling, Zagorski's execution is likely to go ahead at the end of the ten-day delay imposed by Gov. Haslam, during which the state will consider the inmate's request to be put to death by electrocution. Once that decision is made, the state Supreme Court will then issue a new execution date for Zagorski.
Tennessee last carried out a three-drug lethal injection execution in August, the state's first since 2009, after Governor Haslam denied a clemency request from Billy Ray Irick. The drug used in that execution, midazolam, has widely been reported to cause extreme pain during execution.
In July, ahead of Irick's execution, Bishop Spalding and Bishop Stika were joined by Bishop Martin Holley of Memphis and wrote a joint letter to Gov. Haslam asking him to put an end to the death penalty in the state.