In short:

Experts say death penalty via lethal injection is not as humane as people are led to believe.

Lethal injection has a botch rate that is double of all other methods.

Christa Pike's lawyers have moved for her sentence to be life in prison with no parole.

Lethal injection has often been portrayed by United States authorities as a humane form of execution, however US legal academics say the botched execution of Christa Pike has exposed it as anything but.

Warning: This story contains details that may be distressing for some readers.

The now 50-year-old convicted murderer regained consciousness in a Nashville Hospital on Wednesday, a week after surviving her planned lethal injection at Nashville's Riverbend Maximum Security Institution.

The exact failure point in Pike's execution remains unclear but her legal team has alleged that up to seven syringes were used and that one was "bent in a 90-degree angle".

They said she sustained significant injuries including blistering to her arms, symptoms medical advisors said matched what could be expected if the drugs were injected in tissue under her skin, rather than into her veins.

The state of Tennessee has not ruled whether there will be a second attempt to execute her, 30 years after she was sentenced for the torture and murder of classmate Colleen Slemmer.

University of Richmond law professor Corinna Barrett Lain, a former prosecutor, said the events in the execution chamber showed perceptions of lethal injections were "warped".

"With all of the other methods, you have to see the blood of the firing squad or smell the sickly smell of burning flesh with the electric chair or see people gasping and retching with the gas mask or the gas chamber," she said.

"With lethal injection, we get to tell ourselves that these people are just drifting off into forever sleep."

Professor Barrett Lain, whose research has focused on the death penalty, said that one in three lethal injections failed in 2022, up from the historic botch rate of between 7 and 8 per cent nationally.

"Lethal injection is nothing like what we think," she told 7.30.

"It is a delicate medical procedure that has all of the error prone aspects of a medical procedure. All the needs for precision of a medical procedure but it has been warped to suit the execution settings needs.

"The people who are actually pushing the syringes are non-medical prison guards.

"I've seen one-hour-long, two-hour-long, three-hour-long executions by lethal injection, autopsies with 12, 14, 16, 18 puncture wounds.

"What we see from autopsies is that 84 per cent of those executions by lethal injection show acute flash pulmonary edema. That is to say, prisoners are drowning in their own fluids."

One of the reasons that can occur is because the bolus injection, a short procedure, which is usually done bedside in a clinical setting is pushed from a distance in lethal injections.

"It's actually a syringe that is pushed from another room through seven-feet (2.13m) of tubing."

Botched executions, sub-par drugs

Another reason lethal injections have a high botch rate that is double of all other execution methods is that pharmaceutical manufacturers have imposed restrictions on access to drugs for the purpose of execution.

A United States Justice Department review in 2019 referred to reporting that showed the states were instead sourcing drugs from compounding pharmacies.

Professor Barrett Lain said the same access restraints prevented the use of voluntary euthanasia drugs in lethal injections.

"Why are they pushing this?" she asked.

"They can't get the drugs. They can't get the medical professionals they need to do this competently. They can't get access to the veins," she said.

Tennessee is one of more than half of all US states to still have the death penalty and Pike's failed execution was the second in the state this year.

Corrections staff aborted the execution of convicted triple-murderer Tony Carruthers in May, when they were unable to locate a vein.

Washington based non-profit Death Penalty Information Center has not taken a position on the penalty itself but said Tennessee's history is particularly concerning.

Executive director Robin Maher said Tennessee has a history of not getting executions right.

"In 2022, we saw several botched executions. They came up with a new new protocol and new commissioner and then we saw two more botched executions," Ms Maher said.

"So clearly, something is very, very wrong at the Tennessee Department of Corrections, that they cannot manage to figure out a way to get through these executions without making terrible mistakes and causing all kinds of additional pain and suffering.

"Tennessee officials, like many officials in other states, when it comes to the death penalty, have decided that secrecy and silence is the best way forward and we strongly disagree."

Pike's botched execution has placed the death penalty in the USA in the international spotlight.

It occurred in the same week that President Donald Trump ordered the execution by firing squad of Nidal Hasan, the former US Army psychiatrist who killed 13 people in a shooting rampage at Fort Hood, Texas, in 2009.

Public support for the death penalty in the US peaked in 1994, according to an annual Gallup poll.

Since then there has been a steady decline with the 2025 poll revealing the lowest rate of support in 50 years, although 52 per cent of American remain in favour.

Pike's lawyers have called on Tennessee Governor Bill Lee to commute her sentence to life in prison without parole.

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