Lawyers for a Georgia man set to be executed Thursday for killing his ex-girlfriend and her friend asked the state parole board to spare his life and challenged the constitutionality of his sentence in court.

Scotty Garnell Morrow is set to be put to death Thursday at the state prison in Jackson. He was convicted of murder in the shooting deaths of ex-girlfriend Barbara Ann Young and her friend Tonya Woods at Young's Gainesville home in December 1994. A third woman also was shot but survived.

After holding a closed-door hearing Wednesday the State Board of Pardons and Paroles rejected his clemency request. As is customary, the board did not give a reason for the rejection, saying only that it had reviewed the facts and circumstances of the case.

In seeking clemency, attorneys for the 52-year-old death row prisoner argued that impassioned, spontaneous killings such as the ones Morrow was convicted of are rarely punished by the death penalty. The lawyers said commuting his sentence to life in prison, with or without possibility of parole, would bring his punishment more in line with sentences for others convicted of murder under similar circumstances.

Separately, in a petition filed Tuesday in a county court, the inmate's lawyers argued that Morrow's death sentence is unconstitutional because it was improperly imposed. They said the judge in the case ultimately decided which of the two murders deserved the death penalty, a decision that the U.S. Supreme Court has ruled must be made by a jury.

State attorneys argued that those claims had already been raised and rejected by courts.

When jurors recommended the death penalty for Morrow, they failed to indicate on their verdict form which of his two murder convictions merited the death sentence — or whether both did. A couple of weeks after sentencing, in July 1999, the judge held a hearing and said he recognized the judgment "was not fully compliant with the statute." He entered a new order imposing a death sentence specifically for the first count of the indictment, Young's murder.

Morrow's attorneys argue that's unconstitutional because there was no indication of a unanimous jury decision that death was the right sentence for either of the murders. It's possible that some jurors may have thought death was appropriate for Young's murder but not for the murder of Woods and vice versa, they argued.

Morrow's lawyers asked the judge to delay his execution to give the court an opportunity to consider these arguments.

State attorneys said that those arguments are procedurally barred after previous courts rejected them. But even if they weren't, Morrow's death sentence isn't unconstitutional, they said.

"The record clearly establishes that the jury recommended at least one death sentence for Morrow's murders," they wrote.

A judge on Wednesday agreed with the state that the arguments had already been heard and dismissed the petition. Morrow's attorneys appealed to the state Supreme Court.

Morrow killed Woods and Young on Dec. 29, 1994, when he went to Young's home to try to win her back. Woods told him to leave, saying Young had just been using him for money and companionship while her "real man" was in prison. An inability to properly process and express emotions resulting from a violent childhood caused Morrow to snap, his lawyers wrote in the clemency petition.

In the petition, Morrow's lawyers ask the parole board to consider beatings and rape that Morrow suffered as a child, evidence the trial jury never heard. They also said Morrow feels deep remorse for the pain and loss he caused the Woods and Young families and is particularly devastated at having deprived Young's children of their mother.

Morrow would be the first prisoner put to death by Georgia this year if the execution goes forward.