LIVINGSTON (AP) – Condemned inmate Cary Kerr acknowledges that the prospect of becoming the first Texas prisoner to be executed with a new drug is unsettling.

“It’s very scary,” Kerr said recently from a tiny visiting cage outside death row. “I’m not volunteering to test nothing for the state.”

Kerr, 46, is set to die Tuesday in Huntsville for the rape and slaying of a woman near Fort Worth 10 years ago.

Texas will use pentobarbital as one of the three drugs in its lethal injection process because of a nationwide shortage of sodium thiopental, a sedative used in the drug mixture in the 466 executions since the state resumed carrying out capital punishment in 1982.

Another Texas inmate, Cleve Foster, had been set to die using the new drug in early April, but the U.S. Supreme Court halted his punishment to take a further look at his case.

Pentobarbital has won approval in the courts for executions in Oklahoma and Ohio.

“This is a drug not even supposed to be used on pets and yet they’re saying we’re using it on a human being?” Kerr said, repeating unsuccessful arguments made in earlier legal challenges. “That’s preposterous it’s come to that.”

Kerr’s lawyers focused their appeals before the Supreme Court Monday on whether he received effective legal help earlier in his case. The high court is reviewing an Alabama case where similar claims have been raised.

Last week, the Texas Court of Criminal Appeals refused an appeal from Kerr and the Texas Board of Pardons and Paroles turned down a clemency request.

With toxicology tests showing a blood-alcohol level approaching 0.50 — six times the legal limit for drivers — there’s little dispute Pamela Horton was drunk on the night a decade ago when she was killed.

Kerr said he and Horton, 34, a former neighbor in a trailer park, had visited a couple of bars, wound up at his place, had sex and then fell into an argument. Kerr said she left his home alive.

“I’ve never denied being with her,” he told The Associated Press, adding that he told police everything he knew. “And yet here I am sitting on death row.”

Tarrant County prosecutors convinced a jury in 2003 that Kerr had a history of violence toward women. They said he took advantage of Horton’s condition, raped, beat and strangled her and then dumped her body on a street in Haltom City, about five miles north of Fort Worth.

Court documents show a taxi driver found the woman’s body at about 2 a.m., on July 12, 2001. Kerr showed up and told EMTs he thought he knew the woman.

When police arrived, they looked in Kerr’s car and saw a purse. Kerr said it might belong to the victim. They also found a long strand of blond hair on him. Horton was blond, Kerr dark-haired.

He was arrested.

From death row, Kerr said he was “half drunk” after consuming “about 18 beers.” Asked if he was so drunk that he couldn’t remember killing Horton, he replied: “Oh, no. That’s not possible. I don’t see how anybody can do that.”

He said detectives focused their investigations on him after he told them that the pair had argued.

“They didn’t look at nobody. They looked at me and me only,” Kerr said.

Wes Ball, Kerr’s lead trial attorney, said he remained disappointed that jurors convicted Kerr.

“Having represented a number of unscrupulous individuals accused of capital murder, it’s never been my experience that someone who would kill someone and remove the body away from the scene of the crime and dump it on the side of the road would suddenly show up and make sure they can be identified,” Ball said. “It just didn’t make any sense.”

Evidence showed authorities found pieces of Horton’s clothing, some of the items severely torn, at Kerr’s home. Jurors also heard from two of Kerr’s ex-wives, a girlfriend and a former neighbor who testified about his violence toward them. Kerr pleaded guilty to assault with intent to do bodily harm in a 1999 case, and was sentenced to a year in jail.

“They just made up all that stuff and the jury bought it hook, line and sinker,” Kerr said.

Horton’s aunt, Joann Mazyck, who said she helped raise Horton, wished Kerr would at least show some remorse.

“I want him to be punished,” she said. “I hate to use ‘dead.’ I just want to know he’s not here.”

Kerr would be the third prisoner executed this year in Texas, the nation’s most active death penalty state. At least seven other inmates have execution dates nearing, including four in June.

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