An Arizona inmate apologized to the family of the man he killed and his own family, said his life was one mistake after another and started crying before he was injected with a lethal drug Thursday.

Robert Charles Towery, 47, convicted of killing Mark Jones, of Scottsdale, while robbing his home in 1991, was the second inmate put to death in the state in the past eight days.

"I would like to apologize to Mark's family and friends for what I did to them. I would like to apologize to my family. So many times in my life I went left when I should have gone right and I went right when I should have gone left. It was mistake after mistake after mistake," Towery said as his final words.

He started weeping after he looked at his family members and said, "I love my family." Then he took a few heavy breaths and appeared to fall asleep.

The execution took nine minutes and Towery was declared dead at 11:26 a.m. following an unspecified delay at the state prison in Florence.

Towery's attorneys made several unsuccessful last-minute arguments in an effort to spare him, including a request on Wednesday with the Arizona Supreme Court to reduce his sentence to 25 years to life in prison because Towery's accomplice spent less than 10 years behind bars.

Randy Allen Barker, the other man convicted, was given a plea deal for testifying against Towery and was released in 2001.

Towery's lawyers argued that although Towery strangled Jones, Barker was holding the gun, watched the prolonged killing and "exhibited extreme indifference to human life."

"Mr. Barker was present while Mr. Towery choked Mr. Jones, walking in and out of the bedroom," according to the filing. "He could have stopped Mr. Towery. ... Mr. Towery was unarmed, and had neither physically assaulted nor threatened Mr. Barker."

Given Barker's lenient sentence, putting Towery to death would be grossly disproportionate, the attorneys argued.

The court turned them down less than two hours after receiving the filing. The U.S. Supreme Court also denied a review of the case and a stay of execution.

The attorneys said that after the killing, both men disposed of Jones' car, split the cash they had stolen, and that Barker gave most of the stolen items to family and friends.

In other filings, Towery's attorneys argued that the trial court failed to consider so-called mitigating factors that merited a sentence of life in prison over the death penalty, including an extremely difficult childhood that included abuse at the hands of his mother and longtime drug abuse.

Towery himself asked the state's clemency board last week to show him mercy and give him a sentence of life in prison. He also apologized to Jones' family for killing him.

"I have the deepest regrets for what I did and I'm truly sorry for their loss, for what I did to them," he said. "It's a terrible thing that I did and it should never have happened. ... I can only pray that they will find peace and that someday they'll be able to forgive me."

He said that he and Barker decided to rob Jones because Towery knew he had money and that they discussed killing him beforehand.

At Towery's trial, the state's case rested on Barker's testimony.

Barker testified that he and Towery had discussed robbing Jones for several weeks before they went to his home on Sept. 4, 1991, with a made-up story that their car had broken down and they needed to use his phone. Jones, who had met Towery before, agreed.

Barker said that Towery then pulled a gun on Jones and Barker handcuffed him. The two loaded Jones' Lincoln Continental with electronics, jewelry, credit cards and cash from the home, before they took him to his bedroom at gunpoint.

Towery had Jones lay face-down with his hands tied behind his back and then tried to inject his arm with battery acid, Barker said. When that had no apparent effect, Towery then made a noose out of plastic ties and tried to strangle Jones, Barker testified.

Barker said Jones didn't put up a struggle but made choking and gagging noises. Because Towery didn't believe Jones was dead, he made another noose and choked him again, Barker said.
Jones' body was found the next day.
Barker and Towery were arrested after a security guard identified them from a photo lineup. He reported seeing the two ditch the Lincoln at an apartment complex.
Towery said at trial that he wasn't in Jones' home at all when the killing occurred and that Barker must have done it.

Towery's last meal was a porterhouse, sauteed mushrooms, a baked potato with butter and sour cream, asparagus, clam chowder, Pepsi, milk, and apple pie and vanilla ice cream.

On Feb. 29, Arizona executed Robert Henry Moormann for killing and dismembering his adoptive mother. Moormann was the first Arizona inmate executed with one lethal drug, as opposed to the state's long-standing three-drug protocol. The same method was used with Towery.

The Arizona Supreme Court will consider whether to approve death warrants for two other inmates on March 20.