Potassium
(Originally published in I, Science Magazine)
Thirty-eight-year-old Kenneth Williams was a black man convicted of murdering two white people and causing the death of a third. On the day of his execution on April 16th 2017, he had been on death row for sixteen years. After being brought into the death chamber and strapped to a gurney he gave a final statement, a rambling apology, which he was still giving when the controversial drug midazolam entered his bloodstream. He broke off and began to speak ‘in tongues’. Three minutes later, eyewitnesses report that his body began to convulse and shake.
Williams’ was the most recent execution to follow the triple lethal injection protocol, which uses potassium chloride alongside an anaesthetic and a paralytic. The protocol was invented in 1977 as a more sanitised alternative to the electric chair or the gas chamber. However, controversy has swirled around the method over the past few years, with pharmaceutical companies backing away from supplying anaesthetics to executioners. Different states have responded to this lack of anaesthetics in a variety of ways; some by reverting to death by firing squads and others by changing to a one drug protocol; essentially affording prisoners the same dignity given to dying pets — injecting them with an overdose of pentobarbital.
The State of Arizona has replaced the usual anaesthetic with the anti-anxiety drug midazolam. Midazolam is not approved by the FDA for use as an anaesthetic by itself and it has been involved in several botched executions.
Eye witnesses to Williams’ death report that he convulsed for around ten seconds and was soon after injected with the paralytic drug. He continued to breathe heavily and groan even after the injection but these movements were dismissed by officials as ‘involuntary’.
The use of a paralytic is controversial because it ensures that convicts are unable to move when they are injected with potassium chloride; a drug which is so excruciatingly painful when injected in high concentrations it is banned for use in animals. In a disturbing post mortem study published in The Lancet, it was found that in 21 out of 43 prisoners, blood concentrations of anaesthetic were low enough for them to have fully experienced the pain as potassium chloride entered their bloodstream. The paralytic would have rendered them unable to speak, scream, or even move a muscle.
Potassium chloride works by interrupting the electrical signals that control the heart’s contractions. The heartbeat is controlled at the top of the heart in the sinoatrial node, a group of cells that are also sometimes called the pacemaker. The pacemaker moves positive ions including potassium in and out of its cells which creates a fluctuating electrical signal. This signal tells the heart to alternately contract and relax, creating the beat that pumps blood around the body.
When injected in high doses, potassium chloride causes death by flooding the heart with potassium ions. This reverses the usual concentration gradient and makes it impossible for the pacemaker to move positive ions back and forth in its usual way and the heart stops beating.
The use of potassium chloride in the euthanasia of domestic animals is condemned by the American Veterinary Medical Association as the pain associated with injecting it is considered too extreme. However, over the last forty years Williams is just one in a line of 1220 people who have been injected with a lethal dose.
The origin of the three drug protocol is an unlikely one. Originally thought up in 1977 by Oklahoma Medical Examiner, Dr Jay Chapman, it was never intended to be more than a quick fix to quell growing public unease with the use of the electric chair and gas chamber. Part of the current controversy surrounding death by lethal injection is that health professionals are not present to administer the drugs or deal with any complications (their professional ethical code forbids it). Chapman has been quoted as saying that when he wrote the law he never imagined anyone who was not qualified to administer these drugs would be doing it. The lack of health professionals present means incorrect dosages, faulty catheter insertion and kinked IV lines are all more likely. There have even been cases, such as that of Charles Warner in 2016, where the wrong drugs were given. Warner spent 43 minutes writhing in agony before he died and his last words were, ‘My body is on fire.’
In Williams’ case, death took the usual 13 minutes. At 11:05pm local time his heart stopped beating and his body was removed.
Williams’ crimes had been considerable. He was convicted of murdering Dominique Hurd and given a life sentence. Only a month later, he escaped from a high security prison killing one and causing the death of another person in a traffic accident. No-one would say that Williams was innocent.
However, if killing is wrong, killing by the machinery of the state must also be wrong. The use of a three drug protocol, which may cause and disguise incredible pain, pain that we all agree would should not even be inflicted on animals, must be doubly so.
