For the first time since Tennessee adopted a new lethal injection protocol, a post-execution autopsy has been released.
It shows that Byron Black, who was put to death Aug. 5, developed pulmonary edema — a form of lung damage that can cause a drowning sensation.
The lung damage could explain why Black showed distress as he died. He groaned for several minutes, and told his bedside spiritual adviser he was in pain. However, his attorneys have raised concerns that the report failed to address other potential causes, such as a poorly administered injection.
Black was the second man to be executed using Tennessee’s pentobarbital-only lethal injection method. Autopsies are standard procedure after an execution. The first man to die under the new protocol, Oscar Franklin Smith, refused an autopsy on religious grounds.
This autopsy revealed that Byron Black developed pulmonary edema during the execution. That’s a form of lung damage that can cause a painful drowning sensation. An NPR investigation published in 2020 found that this damage is incredibly common. Researchers reviewed dozens of post-execution autopsy reports, and they found pulmonary edema mentioned in about 80% of them.
That can happen with any kind of lethal injection method — including the three-drug protocol that Tennessee previously used. But it’s especially likely with pentobarbital. That medication is highly caustic — like Drain-o.
For weeks before he died, Black’s attorneys argued that this form of execution violated his rights in several ways — one being the risk of this lung damage.
The state’s medical witness argued that it was unlikely Black would experience any pain during his execution, whether he developed pulmonary edema.
Dr. Joseph Antognini is an anesthesiologist who has served as a medical expert on behalf of several red state governments updating their death penalty methods. This year, he has performed his services in Louisiana, where officials are implementing nitrogen gassing, and Tennessee, as it goes through a legal challenge to its new lethal injection protocol.
In Davidson County court records, he testified that such high dose of pentobarbital would cause Black and any other inmate to lose consciousness within 20 seconds of administration, and that they would would be unlikely to experience any pain associated with the injection.
Under Tennessee’s lethal injection protocol, the drugs are stored and administered in a room adjacent to the execution chamber. This is to obscure the identity of any prison workers involved in the process.
There is a hole in the wall between the two rooms, and the IV lines are routed through the hole. Then, workers place an IV in each arm. Media witnesses are in the viewing gallery as this happens, but curtains cover those windows until the IVs are established. Once the workers finish the job and leave the room, the curtains open, and the pentobarbital begins flowing into the prisoner being executed.
The curtains opened at 10:31 a.m., and Black showed signs of alertness until about 10:36. It was during this time he groaned, panted, and said, “It’s hurting so bad.”
Black’s legal team told the Nashville Banner the autopsy failed to address other concerns.
For example, his attorneys noted it took several attempts to find a vein, and it was possible the caustic medication was shot into the muscle instead. But the report did not discuss whether there was any damage at the injection site.
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