NASHVILLE, Tenn. (AP) — After more than three decades on death row, Don Johnson weighed the options for his own demise: He could keep a promise to his daughter that he wouldn’t die in the electric chair. Or, he could opt for the chair and avoid a method that he had heard might make him feel like he was being buried alive.

Last May, Johnson was strapped to a gurney and hooked up to an IV. He said a prayer and started singing as toxic drugs flowed into his body. Then came sounds resembling snoring or gurgling and gasping. Finally, after a high-pitched noise, he fell silent.

Johnson, who was convicted of suffocating his wife, was put to death by lethal injection, a method adopted by most states after the electric chair began losing public favor. However, the three-drug combination used by Tennessee and some other states has come under attack by attorneys for death row inmates who say it can cause intense suffering.

Most states have gotten rid of the electric chair, meaning the only option for most inmates across the country is lethal injection. That’s not the case in Tennessee, one of nine states that still allow electrocution, and one of six that allow inmates to choose which way they will die, according to the national Death Penalty Information Center.

In Tennessee, 38 of the state’s 53 death row inmates — those whose crimes predated Jan. 1, 1999 — not only will ultimately be told when they are going to die, but also will have a hand in picking the method of their execution.

“We are putting people in a cage for a number of years telling them that they are going to be killed and making them choose one of two ways,” noted Joe Ingle, a United Church of Christ minister in Nashville who has spent years ministering to death row inmates.

Inmates’ attorneys have argued that both lethal injection and electrocution are forms of punishment that violate the Constitution’s ban on cruel and unusual punishment. So the choice for inmates is a nearly impossible one.

“They know one is going to knock them out,” said Dan Mann, a talent booking agent who has been protesting the death penalty in Tennessee and has visited the state’s death row several times a month for nine years. “The other one, they may just suffer.”

Since Tennessee resumed executions in August 2018 — a pace topped only by Texas — 5 of 7 inmates have chosen the electric chair. The fifth is Nicholas Sutton, scheduled to die on Feb. 20 for the 1985 murder of a fellow inmate. Other than Tennessee, the last state to carry out an electrocution was Virginia, in 2013.

“We know that electrocutions have failed. We know that flames could erupt at any moment,” said Johnson’s attorney Kelley Henry, who is also supervisory assistant federal public defender.

“We know that the organs are burned. … But is it better to experience one to five minutes of an electrocution than a potential 15-to-20-minute lethal injection? Who can know?” Henry said.

Complicating the situation, Henry said, is that if inmates speak out publicly about the decision they face, “it could be misconstrued as exercising a choice and thus a waiver of their right to challenge what are unquestionably torturous forms of execution.”

Victims advocates and the family members of those who died at the hands of condemned inmates have little sympathy. The inmates’ difficult choice, they say, is nothing compared to the pain and suffering their victims experienced.

Lee Hall was sentenced to death for the 1991 murder of Traci Crozier.

Hall “executed her and she had no choice,” Crozier’s sister Staci Wooten told a reporter ahead of the inmate’s execution by electrocution on Dec. 5.

Still, attorneys for the inmates have questioned how effectively the state Department of Correction has kept inmates informed about the daunting choices confronting them.

The three drugs used for lethal execution in Tennessee are midazolam, a sedative; vecuronium bromide, a paralytic; and potassium chloride, which stops the heart.

Officials have said midazolam renders an inmate unconscious and unable to feel pain. But during a legal challenge to the protocol, expert witnesses for inmates testified in July 2018 that midazolam wouldn’t prevent inmates from feeling pain. They also said Tennessee’s three-drug combination would cause sensations of drowning, suffocation and chemical burning while rendering them unable to move or call out.

In now public court documents, Henry contended that Sutton and Tennessee inmates executed by electrocution were not informed about a problem with the final drug, potassium chloride, which Henry likened to “injecting rocks into the veins.”

A heavily redacted email from the state Department of Correction that was included in Henry’s court filing showed the problem arose several months after Johnson’s execution, leaving unanswered the question of whether his batch of drugs was tainted, and if the issue has been since addressed.

A separate email from November said Tennessee was having a “difficult time” obtaining the paralytic drug, vecuronium bromide. The state has not said whether that problem was resolved.

It took a change of heart for Johnson to pick lethal injection. Several years before his 2019 execution date, he had quietly selected the electric chair after determining it was the more expedient and humane option, according to his spiritual adviser, John Dysinger.

He reversed course after reconciling with his daughter, Cynthia Vaughn, who had previously declared she wanted “the freak to burn” but later said she could not bear the risk of a botched electrocution.

“For him the choice was one last act of love,” Henry said. “Should I have talked him out of it? I don’t know.”

Dysinger said Johnson hoped dying by lethal injection would help answer some of the questions about the drugs used to kill inmates.

“He was willing to go through that if his execution could somehow make it better for those on death row,” Dysinger said.

“In many ways, death was a relief.”