Brad Sigmon opted for the controversial method rather than the electric chair or lethal injection, which are the other two state-approved procedures.
It makes him the first inmate in the US to be executed by a firing squad in 15 years.
Sigmon was handed the ultimate punishment by a jury in 2002 after being convicted of killing his former girlfriend’s parents, William and Gladys Larke.
He bludgeoned the couple to death with a baseball bat in their Greenville County home in 2001, as well as abducting their daughter Rebecca Barbare at gunpoint – but she managed to escape.
Three state corrections department volunteers fired rifles at Sigmon’s chest just after 6pm local time on Friday, fatally shooting him with specially designed bullets.
The 67-year-old was pronounced dead by a doctor at 6.08pm, according to the South Carolina Department of Corrections.
Brad Sigmon, 67, was put to death on Friday (South Carolina Department of Corrections)
He was strapped to a chair during the execution, which had a basin underneath to catch blood, the BBC reports.
Sigmon told witnesses that he wanted his last words to be ones of ‘love and a calling to my fellow Christians to help us end the death penalty’.
He said: “An eye for an eye was used as justification to the jury for seeking the death penalty. At that time, I was too ignorant to know how wrong that was.
“Why? Because we no longer live under the Old Testament law, but now live under the New Testament.”
After he made his final statement, a hood was placed over Sigmon’s head and a curtain which concealed the firing squad was opened.
Shots were then fired simultaneously at Sigmon from around 15ft (4.6m) away, without a countdown.
Reports claim that those carrying out the execution were aiming at a red bullseye target on Sigmon’s chest, which had been placed over his heart.
Jeffrey Collins, a reporter for the Associated Press, described seeing the killer’s chest rise and fall several times after the bullets penetrated him.
He was strapped to a chair and had a hood placed over his head (South Carolina Department of Corrections)
The ammunition used was .308 Winchester Tap Urban bullets, which are made to break apart on impact and inflict maximum damage.
People watching the execution from behind bulletproof glass were offered ear plugs by prison guards to protect their ears from the gunshots, according to the Post and Courier.
Despite Sigmon’s deciding to be killed by a firing squad, his lawyer Bo King has alleged that information about the lethal injection process was withheld from the killer.
“Brad only wanted assurances that these drugs were not expired, or diluted, or spoiled – what any of us would want to know about the medication we take, or the food we eat, much less the means of our death,” he said in a statement after Sigmon’s death.
“It is unfathomable that, in 2025, South Carolina would execute one of its citizens in this bloody spectacle.”
Sigmon had hoped for a last minute stay of execution, which was ultimately denied by South Carolina’s governor.
King claimed his client had been suffering from mental illness at the time of the murders and suggested that what he chose for his final meal proved he was a changed man.
“Brad is someone who, for his last meal, asked to get three buckets of original recipe Kentucky Fried Chicken so he could share with the guys that he’s incarcerated with on death row,” he told WYFF-TV earlier on Friday.
“With his last meal, he wanted to share something special with them.”
King later said that Sigmon’s request to share the food had been denied.
