A South Carolina inmate on death row has chosen the firing squad over the electric chair for his method of execution scheduled later this month.

Richard Bernard Moore, 57, is also the first state prisoner to face the choice of execution methods after a law went into effect last year, making electrocution the default and giving inmates the option to face three prison workers with rifles instead, as reported by NPR.

Moore has spent more than 20 years on death row for murdering a convenience store clerk James Mahoney in Spartanburg.

If his execution pushes through on April 29, he would be the first prisoner to be put to death in the state since 2011.

Last year, a new rule made electrocution the default method of execution for death row inmates, with the choice of facing three prison guards with firearms instead. It resulted in a ten-year delay, which prison authorities blamed on a lack of drugs required to administer lethal injections, per a Sky News report.

Pressured To Choose Firing Squad?

Moore's lawyers have asked the California Supreme Court to postpone his execution while another court determines whether one of the two options is cruel and unusual punishment.

Last month, the South Carolina correction department announced that it had finished establishing protocols for firing squad executions and had completed $53,600 in death chamber refurbishments in Columbia, including the installation of a metal chair with restraints facing a wall with a rectangular opening 15 feet (4.6 meters) away.

Three volunteer prison workers will drill their weapons on the condemned prisoner's heart in the event of a firing squad execution.

Moore claimed in a written statement that while neither method was legal or constitutional, he was more firmly opposed to death by electrocution and only chose the firing squad because of pressure.

 "I do not intend to waive any challenges to electrocution or firing squad by making an election," Moore noted.

Last week, Director of the Corrections Department Bryan Stirling stated in an affidavit that the department was still unable to procure the drugs because producers and compounding pharmacies approached by the state refused to cooperate.

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Mistake-Free Execution Method

During his 2001 trial, Prosecutors said Moore went into the store seeking money to sustain his cocaine habit and got into a fight with Mahoney, who drew a gun, which Moore wrestled away from him.

Prosecutors said that a shootout occurred when Mahoney brought out a second weapon. Moore shot Mahoney in the chest. Moore allegedly left a trail of blood as he searched the shop for cash, walking two times over Mahoney.

Washington-based charity Death Penalty Information Center said that only three people had been executed by firing squad in the United States since 1976.

According to the institute, South Carolina is among eight states that still use the electric chair, and one of four permits a firing squad.

Ronnie Lee Gardner, the last person executed by firing squad in the United States, chose that method because there would be no errors.

Witnesses said that a hood was placed over his head and a target was strapped to his chest before a five-member squad of state law enforcement agents shot a series of fatal gunfire, the New York Times reported.

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