By MICHAEL GRACZYK Associated Press

HUNTSVILLE (AP) – A North Texas man convicted in the 1998 torture-slaying of a 19-year-old mentally challenged woman apologized profusely Tuesday just minutes before he was executed, exactly 13 years after the murder.

Michael Wayne Hall, 31, received lethal injection less than an hour after the U.S. Supreme Court refused to stop his punishment for the abduction and murder of Amy Robinson. Hall was pronounced dead at 6:23 p.m. at the Huntsville Unit of the Texas Department of Criminal Justice.

The second man convicted in Robinson’s death, Robert Neville, was executed five years ago.

“I would like to give my sincere apology to Amy’s family,” Hall said as he was strapped to the death chamber gurney. “We caused a lot of heartache, grief, pain and suffering, and I am sorry. I know it won’t bring her back.”

Speaking just above a whisper, his voice shaking and eyes watery, Hall said he wasn’t the same person and repeatedly asked for forgiveness. Relatives of his victim stood a few feet away, looking through a window.

“I am not crying for myself, I am crying for the lost and those that are dying for their sins,” he said. “I’ve been locked up 13 years. I am not locked up inside. All these years I have been free. Christ has changed me. Here I am, a big strong youngster, crying like a baby. I am man enough to show my emotions and I am sorry.

“I am sorry for everything. I wish I could take it back, but I can’t.”

Nine minutes later, he was pronounced dead.

Lawyers for Hall unsuccessfully argued that he was mentally impaired and ineligible for the death penalty under a Supreme Court ruling that bars capital punishment for those with an IQ under 70.

“Mr. Hall’s history of mental retardation reaches back to his childhood,” attorney Bryce Benjet said in his appeal.

Hall’s lawyers went to the Supreme Court a day after the Texas Court of Criminal Appeals — the state’s highest criminal court — refused to stop the punishment. Similar appeals also failed in other courts.

Hall was 18 when evidence showed that he and Neville, a 23-year-old paroled burglar, decided to abduct and kill Robinson, who worked at a Kroger store in Arlington, just west of Dallas. The men had been fired from jobs at the same supermarket.

Robinson had a genetic disorder called Turner’s syndrome, a rare chromosome condition found only in women and characterized by short stature and lack of sexual development at puberty. Prosecutors described her as mentally challenged and trusting.

Authorities said Hall and Neville stopped Robinson along the bike route they knew she took to work and offered her a ride. She accepted.

They drove her about 12 miles to a remote area of Tarrant County where Neville shot at her repeatedly with a crossbow but missed. They also shot her numerous times with a pellet gun and a .22-caliber rifle, prosecutors said.

“Target practice,” they bragged to reporters after they were arrested two weeks later trying to cross into Mexico near Eagle Pass. They also told reporters how they laughed as Robinson pleaded for her life.

After their arrests, Neville told the Fort Worth Star-Telegram that he and Hall wanted to become serial killers whose victims were racial minorities. Robinson was part Native American.

“We had a bet going to see who could shoot and kill the most people between the two of us,” Neville said.

Hall said they returned to her body a few days later when he removed her keys and $4 or $5 from her pocket, then he and Neville shot her several more times.

Robinson’s sister, Amanda, refused to forgive him and said she attended the punishment Tuesday night so her face would be the last face Hall saw.

“It was fake, he wasn’t sincere,” she said of Hall’s apology. “He was really scared. You could tell … I just don’t think he was remorseful.

“What about the pain he caused Amy? I’m glad it was on Feb. 15, but it should have been a lot sooner.”

“They turned a bad day into a good day,” another sister, Ruth, said. “I feel like a weight’s been lifted off my shoulder.”‘

In an interview last week, one of Hall’s trial lawyers, Bill Harris, said he believed Neville was the person who killed Robinson and “cooked up the whole scheme.”

“I’m personally convinced Michael is mentally retarded, that he fits the classic definition,” Harris said. “If you got to know Michael for very long, you got to understand he was pretty profoundly limited. Half the time he didn’t remember my name.”

Harris said even if Hall was taken from death row and put in the general prison population, life would not be easy.

“People with his mental limitations frequently are targets of some abuse and can be taken advantage of by other prisoners,” he said.

At least four other Texas inmates have executions scheduled in the coming months. Timothy Wayne Adams is set to die next week for fatally shooting his 19-month-old son during an argument with his estranged wife at their apartment in Houston.

(Copyright 2011 by The Associated Press. All Rights Reserved.)

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