Oklahoma City ? A federal judge on Thursday denied a request by a condemned Oklahoma killer for a stay of execution while the state’s lethal injection method is challenged.

Corey Duane Hamilton, 36, is scheduled to die by injection Jan. 9 at the Oklahoma State Penitentiary in McAlester for the murder of four people during a 1992 robbery of a fast-food restaurant in Tulsa.

Hamilton’s attorneys asked the court to delay the execution, contending Oklahoma’s injection procedure “creates a severe and unnecessary risk of failure and conscious physical suffering.”

But Judge Stephen Friot denied Hamilton’s motion for a preliminary injunction, ruling from the bench that Hamilton’s attorneys did not prove that their client would suffer “torture or a lingering death.”

Friot said there was virtually no likelihood that Hamilton could prove a violation of his rights under the Eighth Amendment of the U.S. Constitution, which prohibits cruel and unusual punishment.

“Mr. Hamilton’s desire for a risk-free and pain-free execution pales in comparison to the public’s interest for justice,” Friot said.

Hamilton’s attorney, Rob Nigh, said he plans to appeal.

During Thursday’s hearing at the federal courthouse in Oklahoma City, the court heard from Florida defense attorney Neal Dupree, who witnessed the botched execution of Angel Diaz earlier this month in Florida.

Dupree, who testified via telephone, said he watched as Diaz grimaced and gasped for breath for more than 10 minutes after the lethal combination of drugs was administered.

“He was grimacing. His jaw became clinched,” Dupree said. “He appeared to me to be in a lot of pain.”

Following Diaz’s execution on Dec. 13, Florida Gov. Jeb Bush issued a moratorium halting all executions until the Diaz matter is fully investigated. It was later determined the needles used to inject the lethal cocktail pushed through Diaz’s veins and into surrounding tissue.

Hamilton also testified via telephone, telling the court his filing of a request for a preliminary injunction was delayed because his previous attorneys wanted to delay filing it until all of his appeals were exhausted.

Nigh also questioned Marty Sirmons, the warden at the Oklahoma State Penitentiary, about the qualifications and training requirements for the state’s execution team.

Sirmons, who has been warden at OSP since January, said he wasn’t aware of any specific training requirements for the doctors or the technician who inserts the intravenous lines into the inmate’s arm.

Sirmons said some minor changes to execution procedures have been implemented since the June 1 execution of John Boltz, who had to have an IV line inserted into the femoral artery in his leg after technicians were unable to find a suitable vein in his arm. Sirmons said inmates now must undergo physicals before an execution to screen them for any potential problems and that additional medical supplies will be kept on hand.

After Wednesday’s hearing, Nigh said until Oklahoma and other states abolish the death penalty, there inevitably will be cases of botched executions.

“The Diaz execution (in Florida) was horrific, and there have been executions in Oklahoma that are horrific,” Nigh said. “What we ought to talk about is whether we should be doing it (capital punishment) at all.”