The deadly injection ended a horrible execution in the past. But after a series of failed deaths, his humanity was questioned. Are there any other options?

Warning: This story contains details about an execution method that might make some readers sad.

His last words were "I love you", followed by a Muslim prayer. Then Charles Brooks Jr - a convicted murderer - looked away from his girlfriend and felt death creeping in.

She was lying on a white stretcher, dressed from head to toe in the 80s fashion, including gold pants and shirt with all the buttons open. He had an intravenous line in one hand and a doctor hovered nearby. The man could be a hospital patient.

Instead, his last moments were spent in the death room in a Texas prison. It was 1982 and this was the first time a lethal injection had been used to kill a criminal in the United States.

Prior to this pioneering moment, the nation's favorite execution mode was the electric chair, which is now widely regarded as torture. It was so hard, sometimes the victim's eyeball would appear and lean on their cheeks. Regularly set the hair on fire, lead the guards to extinguish the nearby firefighters, just in case.

Deadly injections are hailed as better and more technologically advanced, without blood and no screams. One of the witnesses of Brooks's death said that he just yawned and stirred his stomach. A few minutes later, a doctor said, "I say this guy is dead."

To this day, this method is the first choice in every US state where the death penalty is legal. But that may not be as peaceful as it looks. The problem is, nobody really checked. No research or testing whatsoever.

Betty Lou Beets was convicted of killing her fifth husband in 1985 and executed by lethal injection in 2000

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Back in 2005, when more than a thousand deaths-by-injection had occurred, the team of scientists decided to review it. Led by Leonidas Koniaris, a surgeon based in Indiana, Indianapolis, they studied execution records from Texas and Virginia and found that 44% of inmates may have been awake when they died - and possibly in painful pain. They can not squirm or scream, because toxic cocktails contain muscle paralysis.

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Some executions have failed

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Further research revealed one drug, which was supposed to stop the heart, did not work. "What comes from that data is a very, very disturbing conclusion that the mechanism of death suffocates," he said. "It's a nightmare scenario. If you retreat, you may say we have just stepped away from a brutally visual method of killing people. "Although the majority of Americans agree with the death penalty, very few think it should be painful.

Now the ongoing shortage of drug executions has led some countries to experiment with alternatives. As a result, some executions have failed, including one in which people reportedly took two hours and 640 breaths before he died. Safe to say a deadly injection in a crisis.

Is there a more human choice?

For thousands of years, execution is a spectacle that will be enjoyed by the public. From drowning people into sacks with animals, to eject their lungs through their backs, humans seem to have no shortage of imaginative ideas - and little moral doubt about enacting them.

For thousands of years, execution is a public spectacle

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In ancient Persia, there was "schapism," where the victims were sandwiched between two rowboats - one above the other, with arms and legs sticking out - then covered with milk and honey and allowed to be eaten alive by pests. Meanwhile, a traveler who visited Delhi, India, in the 14th century, reported that elephants had been trained to cut prisoners into pieces using blades attached to their fangs.

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Guillotine

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However, interest in capital punishment that is more humane is hundreds of years in its making. The movement began in 1789, with the introduction of guillotine. At that time, the French Revolution had just begun and the heads of Parisian nobles began to spin. After a series of deaths, protracted executions - sometimes several ax blows are needed - it is clear the process requires some modernization.

Enter Joseph-Ignace Guillotin, a doctor who decides that the execution should be more humane. He suggested using guillotines instead, boasting in his speech "Now, with my machine, I cut your head in the blink of an eye, and you never feel it." They are then named after him, though he does not actually find them.

The guillotine involved a sloping knife, hung over the victim by a wooden frame. Some models also feature a collection basket for their heads. Proven faster and more reliable than beheading by hand, because of the weight of the knife.

So how human is that? Laboratory mice can provide some clues, since beheadings are the standard way to kill them for some kind of experiment, using small guillotines.

The most widespread form of execution today is hanging

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One study from 1975 reported that the signs of conscious awareness lasted between nine and 18 seconds after the animals were beheaded. This period has been shown in other animals as well, so this could be a plausible proxy for humans.

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Hanging

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The beheading is still being done to this day, especially in Saudi Arabia where 146 people are executed by beheading in 2017. But so far, the most widespread form of execution currently depends.

There are two ways to do: 'short drop' and 'long drop'. As the name implies, the first involves dropping a person from a lower altitude and causing death by suffocation. This is generally considered very painful.

'Decreased length' is considered a more humane option. In a "best-case" scenario, the string will break the second bone in the victim's neck. 'Hangman fractures' also cut the spinal cord, causing their blood pressure to drop to zero in less than a second. Victims usually lose consciousness immediately, although it may take up to 20 minutes for their heart to stop beating.

Death by firing squads has been used for hundreds of years

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The catch is this method requires careful calculation. If the fall is too long, the person's head will come off. If it is too short, they will choke to death. "In my experience, there are many administrative errors that although the method has to work in theory, because of error or incompetence, mistakes happen," said Megan McCracken of Death Penalty Clinic at UC Berkeley. Nothing has been hanged in the US since 1996.

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A firing squad

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Though often associated with war and military crime, deaths with firing squads have recently been re-adopted by the State of Utah as reserves, and it has been used routinely in North Korea.

In general settings, a criminal is tied to a chair with a hood over their head. Then five shots of anonymous gunfire on their chests. One pistol containing empty.

In 1938, the same state used a method to execute a 40-year-old man, John Deering, who was convicted of murder. He took the unusual decision to connect himself with the electrocardiogram when it happened, so we had an idea of ​​how fast this method worked.

The monitor showed that Deering's heart stopped beating only 15 seconds after being hit. It is impossible to know for sure how long he was in pain, but once again the rodents can provide some clues. A 2015 study of heart attacks in mice showed that they were usually followed by a spike in brain activity lasting about 30 seconds, which could explain why those who survived the near-death experience reported increased feelings of consciousness. Then the world becomes dark.

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Electric chair

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The electric chair was first created as a more humane alternative to hanging. Like guillotine and lethal injection, it looks as civilized and scientific. It all started with the terrible report commissioned by the State of New York in 1887, which evaluated 34 ways to kill humans.

Like guillotine and lethal injection, the electric chair was originally seen as a form of civilized and scientific execution

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One of the authors, a dentist, remembers hearing about a drunk dock worker who had touched a generator a few years earlier and died instantly. He came up with the idea for an electric chair, which was used to send an ax killer just three years later.

The honeymoon phase does not last long. It soon became clear to the public that this death was often messy and protracted, with seats earned the nicknames like "Gruesome Gertie" and "Sizzling Sally". Nine US states defend this method as a backup, although this is controversial.

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Hypoxia nitrogen

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Which brings us to the latest idea: "Nitrogen hypoxia", which involves replacing air with inert gases such as nitrogen or helium. It first gained traction after the BBC documentary film presented by former Conservative MP Michael Portillo. In How to Kill a Man, he states that the method is "perfect assassin".

For starters, air is nitrogen 78%, so it's easy to hold. This method is also a very fast death. One study from the 1960s found that volunteers who inhaled nitrogen lost consciousness in about 17-20 seconds. Based on animal studies, it is thought they will stop breathing after three seconds.

There has long been an interest in the more humane methods of capital punishment

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And because the game of biology does not seem to hurt. That's because the body can not really detect oxygen deprivation - just excess carbon dioxide, which moisturizes the blood and causes pain in your legs after exercise. This means it does not feel like suffocating.

So what's it like?

John Levinson, a cardiologist and pilot based in Boston, Massachusetts, has some insight. A few years ago he flew his 23,000 feet (7km) Mooney plane, an altitude where the Earth's atmosphere is thinner and pilots must use supplemental oxygen.

Then he does something risky: he tilts the tip of his mask and continues to breathe. "After about 30 seconds I feel really strange," he said. "I do not have hallucinations, or pain, or confusion, I feel weird. It's not like alcohol or any other substance like that. "

The subtle hypoxic symptoms make it very lethal for pilots at altitude, who may not be aware that something is wrong. It is thought to have claimed the life of a man earlier this year, who appeared unconscious on his small plane before missing in the Gulf of Mexico.

"When it comes to execution, I think people need to understand that the death penalty is not a humane act." - Robert Dunham

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In Levinson's case, he flies with his instructor, who will lower the plane safely if he passes out. The idea is to get a sense of what hypoxia is, so that he can recognize when it happens in the future. Years later, while flying with his wife, he begins to get the same strange feelings. He knew right away and improved his strength in his oxygen channel before anyone got hurt.

Three US states have now authorized this method as a backup. But is this just another mistake?

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No pharmaceutical company wants the drugs used to kill people

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Robert Dunham, a litigator and Executive Director of the Information Center for Death Penalty, certainly thinks so. "The American Veterinary Association and the World Animal Protection both say that nitrogen hypoxia is not appropriate for animal euthanasia," he said. "It's not as fast as it has been advertised - cats and dogs are aware of the deaths that will occur before they lose consciousness and it takes at least seven minutes to kill the pigs."

One of the main problems is that this method depends on the cooperation of the prisoners: if they hold their breath, or their breathing is too shallow, it may take longer to kill them. "I understand, of course, the theory behind it, which suggests it would be a humane method," McCracken said. "But that's far from how it's actually done in the execution room."

According to Dunham, most likely the victim should be drugged first. And this brings us back to the problems facing lethal injection: no pharmaceutical company wants its drugs used to kill people.

"The main problem of the United States is that it does not want a horrible or visceral aspect of death penalty. He wants the prisoner executed, but does not want on his conscience that it kills a person brutally. That's an internal contradiction, "he said.

"When it comes to execution, I think people need to understand that the death penalty is not a human act."