Allen Bohnert, one of McGuire’s federal public defenders, called the execution a “failed, agonising experiment by the state of Ohio”. McGuire’s family has now announced it will take legal action against the state, claiming he suffered cruel and unusual punishment. Whatever the outcome of any legal action, McGuire’s execution has highlighted a growing problem facing the 32 American states now using lethal injection – a critical shortage of the drugs they use to kill. The problem is not new. As early as 2011 the European and American manufacturers of many of the drugs used in the death penalty began banning sales to the various arms of the US penal system on legal and ethical grounds. The US-based global pharmaceutical company Hospira announced in 2011 that it would stop producing one of the most popular drugs used in lethal cocktails, the anaesthetic sodium thiopental. It had earlier moved production of the drug from North Carolina to Italy. Since the Italian government bans capital punishment, it warned Hospira that it would have to monitor its entire supply chain to ensure the drug did not end up in the hands of death penalty states. Hospira chose to end production rather than expose employees to liability. “Hospira makes its products to enhance and save the lives of the patients we serve, and, therefore, we have always publicly objected to the use of any of our products in capital punishment,” the company says on its website.

Hospira’s decision led directly to delays of at least two executions that year, and since then US states have had to investigate the use of other drugs. Missouri turned to another anaesthetic, propofol, but the first execution to use it was halted after the European Union threatened to limit the drug’s export to the US if it was used in an execution. This has led some states to turn to anonymous so-called “compounding pharmacies” to mix batches of drugs. This might replenish stocks, but it opens the states up to further appeals. Fordham University law professor and lethal injection expert Deborah Denno says the McGuire case has added to an ongoing trend of questioning lethal injection and the death penalty more broadly.

She notes that lethal injections are carried out in prison settings not properly set up to undertake such a procedure and often undertaken by people not properly trained to administer drugs. In 2009, executioners in Ohio spent two hours trying to get a secure intravenous line into a condemned man called Romell Broom before giving up. He remains on death row. According to Professor Denno, three states are now considering returning to the firing squad for executions. "A firing squad would be quick and something we could do at a moment's notice," one of the sponsors of the bill, Representative Rick Brattin, told the St Louis Today website last week. "My opinion is they would suffer less than with lethal injection." (On this, Professor Denno agrees.) Other states are abandoning the practice entirely as DNA evidence proves many innocent people have been sentenced to death. In total 18 states have abandoned capital punishment, six in the past five years. Others, such as California and North Carolina, have unofficial moratoriums in place.

In a statement after McGuire’s execution, his daughter Amber said: "It was the most awful moment in my life to witness my dad's execution. I can't think of any other way to describe it than torture." The family of the pregnant woman he raped and murdered, Joy Stewart, said McGuire was “treated far more humanely than he treated her".