COLUMBIA, S.C. (AP) — The U.S. Supreme Court on Thursday refused to stop the execution of South Carolina inmate Richard Moore, a Black inmate whose lawyers say he is the only person on the death's death row convicted by a jury with no African American members.

There were no dissents in the brief order issued by the high court.

Moore is scheduled to die at 6 p.m. Friday by lethal injection at a Columbia prison. The only other chance to save his life is if Republican Gov. Henry McMaster decides to reduce Moore's sentence to life in prison. No South Carolina governor has granted clemency in 44 executions in the state in the past 50 years.

Moore, 59, shot and killed a Spartanburg convenience store clerk in 1999. Prosecutors said Moore came into the store to rob it and was not armed, but took a gun from the clerk who then pulled a second gun. The two fired at each other and Moore was hit in the arm. The clerk, James Mahoney, was killed by a bullet to the chest.

Moore said he came in to buy cigarettes and beer and argued with Mahoney when he was 11 or 12 cents short. Moore said Mahoney pointed a gun at him and Moore wrestled it away. The clerk then fired at him with the second weapon and he shot back, Moore said.

After Mahoney was shot, Moore took about $1,400 from the store and left without calling for help.

Moore's lawyers said no one else on South Carolina's death row started their crime unarmed or ended up killing someone in possible self-defense.

They also said Moore is the only inmate in the state condemned by a jury with no African American members. About 20% of Spartanburg County's residents were Black at the time of the 2001 trial.

Moore has had two execution dates postponed as the state sorted through issues that created a 13-year pause in executions, including the refusal of companies to sell the state lethal injection drugs. That issue was solved by passing a secrecy law.

Moore would be the second inmate executed since the state restarted its death chamber in September. Four more are out of appeals and the state appears ready to put them to death in five-week intervals through the spring. If Moore dies Friday, 30 inmates would remain on South Carolina’s death row.

On Wednesday, Moore's lawyers filed a petition for clemency with the governor that included more than 40 pages of letters pleading for mercy. The letter writers included two jurors and the judge from his original trial as well as a former director of the state prison system, six childhood friends, five relatives and several former attorneys who said Moore still checks on their families after they couldn’t keep him off death row.

Moore is a born-again Christian who mentors his fellow inmates on isolated death row, and if his sentence is reduced to life without parole, his good influence can spread to many more prisoners, his attorneys have argued. He has remained involved in his children's lives behind bars and now has grandchildren he regularly calls, according to the clemency petition.

Moore is remorseful for his crime and would apologize to Mahoney's family if he had the chance, his lawyers said.

“Though he can never make up for the life he took, he has sought to do all he can to better the lives of those around him by bettering himself," attorney Lindsey Vann wrote in papers sent to the governor. "Through prayer and study, he has become a more faithful Christian; through consistent communication and love, he has become a better father (and now grandfather); and through all of this, he has gained maturity and wisdom that makes him a benefit to the prison system.”