Georgia plans to execute Kelly Gissendaner Tuesday, but many details of the lethal injection are top secret. Under a 2013 state law, Georgia corrections officials don't have to publicly identify the manufacturer of the execution drug, the compounding pharmacist who mixes the solution, or much of anything else.

Georgia’s lethal injections weren’t always so secretive. In 2007, the state’s chief medical examiner testified in open court about all the drugs then used for executions, the dosages and the effects on the condemned prisoner.

Dr. Kris Sperry was an expert witness for the state of Florida when a death row inmate challenged that state’s execution protocols after the botched lethal injection of another prisoner.

When Florida executed Angel Diaz in December 2006, the procedure took a remarkable 34 minutes. The intravenous line that was supposed to feed the drugs into Diaz's bloodstream apparently was not properly inserted. The drugs leaked into the muscles of his arm and took far longer than usual to put him to death.

The following day, anticipating a challenge from the next inmate scheduled for execution, Florida’s attorney general hired Sperry – who frequently moonlights as an expert witness in forensic pathology – to help defend the state’s procedures.

In a hearing in Ocala, Florida, in July 2007, Sperry testified that Florida and Georgia used the same combination of drugs for lethal injection. The only difference, he said, was that Florida used heavier doses that would kill an inmate faster.

The recipe for the lethal “cocktail,” according to a transcript of Sperry’s testimony:

  • Thiopental sodium, also known as pentobarbital. Florida administered 5 grams, while Georgia used 2, Sperry said. Any dosage of more than 400 milligrams would leave a person unconscious and in "respiratory depression," he said. "The brain would forget to breathe."
  • Pancuronium bromide. Florida's cocktail contained 100 mg, compared to Georgia's 50. Either dosage, Sperry said, would cause "virtually instantaneous" paralysis and prevent a person from breathing. In combination with the first drug, he said, "the person would be unable to perceive any kind of paralysis because they would have been rendered unconscious."
  • Potassium chloride. This drug – at Florida's dosage of 240 milliequivalents or Georgia's of 120 – would cause "instantaneous cessation or stoppage of the heart," Sperry said.
June 20, 2014 - Decatur - The Atlanta VA Medical Center (VAMC). BOB ANDRES / BANDRES@AJC.COM

Credit: Brad Schrade

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Credit: Brad Schrade

The entire cocktail, Sperry said, would result in “a humane and painless death.”

The judge upheld Florida's execution plan. But the inmate, Ian Deco Lightbourne, who now calls himself Ish'od Gi'hon, sentenced to death for a 1981 murder, remains on death row, his appeals continuing.

Gissendaner, convicted of conspiring to murder her husband in 1997, is still appealing, too, of course, but with far less detail about the execution process than Lightbourne had.