In a legal challenge, the Tennessean reported that the four condemned inmates - David Earl Miller, Nicholas Todd Sutton, Stephen Michael West and Larry McKay - proposed alternative execution methods to the state's three-drug cocktail. The men alleged a firing squad would be more humane than the lethal injection Irick suffered through.
Irick, executed on Aug. 9 for a 1985 rape and murder, was the first to receive the state's new three-drug cocktail. Miller, whose execution is scheduled for December, would be next to die.
Execution viewers watched the first chemical administered; it was midazolam, a sedative.
Irick's stomach moved up and down and his breathing became labored, according to court documents.
"At a certain point, he mostly just closed his eyes, snoring loudly. He appeared almost sleeping," said reporter Steven Hale, a witness to the execution. "Then, they do a consciousness check."
Seven minutes after the midazolam injection, warden Tony Mays yelled Irick's first name twice and pinched the muscle above Irick's collar bone. When he didn't respond, court documents said, Mays signaled to administer the second drug: vecuronium bromide, a paralytic.
Irick's arms were strapped and hands taped down as he lay on the gurney. Paralyzed by the drug, including his diaphragm, the muscle that controls the lungs, court documents said it was impossible for him to move. Three to four minutes later, he was injected with the killing agent, potassium chloride.
"He made a sound, like a choked gasp, and strained against the restraints. Then a movement with his head, then nothing," said Hale. "He seemed to be reacting to something. It was obvious there was a change that happened after the second drug and after the consciousness check."
Many experts have testified that the second and third chemicals are painful. Without anesthetic, vecuronium bromide has been described as the feeling of being buried alive. The Supreme Court likened potassium chloride to "chemically burning at the stake."
In recent years, there have been executions where witness accounts raised questions about whether inmates were sufficiently anesthetized when the killing drugs were administered. These performances have raised questions about midazolam's effectiveness as a sedative in executions, The Washington Post previously reported.
Irick's death followed years of legal battles, concluding with a scathing, near prophetic, dissent from Supreme Court Justice Sonia Sotomayor in his failed 11th-hour application for a stay of execution.
"Although the Midazolam may temporarily render Irick unconscious, the onset of pain and suffocation will rouse him. And it may do so just as the paralysis sets in, too late for him to alert bystanders that his execution has gone horribly (if predictably) wrong," wrote Sotomayor.
Going forward with the execution, she said, and inflicting "torturous" pain, would mean "we have stopped being a civilized nation and accepted barbarism."
Many arguments set forth in the newly filed motion are tenuous, ruled on in Irick's and others' cases. However a few legal challenges continue to be litigated, including the appropriateness of Tennessee's lethal injection protocol.
The motion also outlines alternative, constitutional methods, which the inmates claimed are more humane.
For example, other drugs, such as pentobarbital, have been made available in other states this year, or a two-drug method that does not include a paralytic.
A third suggestion was a firing squad, which the condemned said could be easily done because the Big Buck Shooting Range is on the grounds of Tennessee's Riverbend Maximum Security Institution, where all four are housed.
Firing squads are still used or are on the books in Mississippi, Oklahoma and Utah. Utah officials made it the backup execution option for the state in 2015, due to shortages of lethal injection serums.
Based on the Procedures for Military Executions, the execution manner provides a Plan B, in case of human error or mistake: "Should the medical officer so decide, the sergeant of the execution party will administer the "coup de grace," with a hand weapon, holding the muzzle just above the ear and one foot from the head."
Although they are not part of the Tennessee statute, which lists the electric chair as its official backup method, last week's motion mentioned that firing squads could be reinstated promptly.
In response to recent scarcity of certain drugs, states have turned to experimental and untested drug combinations or explored other execution methods.
Oklahoma announced earlier this year that it would begin using nitrogen gas rather than lethal injections, while others adopted execution using fentanyl.
Execution by firing squad has been called a "dignified execution" by legal experts, though Sotomayor's description of it as barbaric may seem more apropos. Still, according to court documents, it has been an available execution method in the United States for more than 400 years.
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