How does lethal injection work?

- asks Jim from Ohio

November 12, 2007

The U.S. Supreme Court is now closely assessing the answer to this question as they consider the constitutionality of a method of execution that’s used in all but one of 38 death penalty states.

Execution by lethal injection has largely replaced other forms of capital punishment, such as electrocution and the cyanide gas chamber, because it is seen as a more humane way of ending a life. Constitutional law states that capital punishment is only acceptable if it doesn’t violate the Eighth Amendment’s ban on cruel and unusual punishment. A person shouldn’t be aware of or able to sense any pain during the procedure. Lethal injection is thought to adhere to this policy because an initial drug is used to induce a state of unconsciousness where pain can no longer be registered. For the person being executed, subsequent injections that rapidly stop their breathing and heartbeat should occur without their sensing it.

According to the Death Penalty Information Center in Washington D.C., the protocol for lethal injection in most states involves a sequence of three shots that are delivered via intravenous drips inserted in each arm.

The first of the three injections is an anesthetic, sodium thiopental, which is a fast-acting barbiturate that depresses the activity of the central nervous system. This initial shot doesn’t serve as an analgesic (pain killer) that numbs pain nerves, but instead rapidly puts a person into a state of unconsciousness that’s theoretically deep enough to make pain undetectable. The drug amplifies the effect of GABA, a neurotransmitter that depresses brain activity, while also blocking the actions of an excitatory brain receptor, AMPA, which acts in many parts of the brain. The state of unconsciousness can be reached in as little as 30 seconds. A single dose of this anesthetic is intended to last throughout the last two injections to prevent any pain during the moments leading up to death (pronounced after the heart stops beating for a certain amount of time).

After the initial injection, the intravenous line is quickly flushed with saline, a neutral substance commonly used to push a drug into the bloodstream more quickly. Subsequently, pancuronium bromide is administered. It acts as a neuromuscular blocker, preventing a nerve messenger, acetylcholine, from communicating with muscles. The result is a complete muscle paralysis, which causes respiratory arrest since the diaphragm—a muscle imperative to pulling air into the lungs—stops working.

Following another saline flush is the final injection, potassium chloride. This last dosage of chemical floods the heart with charged particles that interrupt its electrical signaling, stopping it from beating. According to a 2002 study in the Journal of Forensic Science, the average length of time from the first injection to death is 8.4 minutes.

The dosage of each drug administered in lethal injection is supposed to be redundant, which means that the amount of chemical contained in each shot is lethal. For example, during surgeries, patients are normally given 100 to 150 milligrams (mg) of sodium thiopental, the initial anesthetic used in capital punishment, over a period of 10 to 15 minutes – while up to 5,000 mg are provided during executions. For pancuronium bromide, 40 to 100 micrograms per kilogram of body weight is normally given pre-operatively (to aid intubation) while a thousand times that amount is used for execution. When all three injections are used in executions, the aim is to put the person into a state of total unconsciousness before they die from a mix of respiratory and cardiac arrest.

Not only that, to ensure that the first injection reliably maintains a sedated state during the entire execution, an effective amount must constantly be in the blood system to prevent any chance of regaining awareness and, in turn, suffering, according to a study published this year in Public Library of Science Medicine. This is especially important when a person being executed could potentially be in a state that incapacitates them from physically showing discomfort while still experiencing it nonetheless. (See an article concerning the controversy over one Florida case in the St. Petersburg Times.)

Improper delivery of the anesthetic, either because an insufficient amount is administered or the IV is misplaced in the arm, is one of many aspects of lethal injections that poses a challenge to its public acceptance.

Researchers also have debated lethal injection. According to a 2005 letter in The Lancet, which looked at post-mortem toxicology reports of executions carried out in Arizona, Georgia, North Carolina and South Carolina, the blood concentrations of thiopental were low enough that 21 out of 49 executions (43 percent) had concentrations that allowed for a regaining of awareness.

This finding was disputed in the same issue by Jonathan Groner, its also gets quickly absorbed into fat and muscle tissue—even after death. When considering this and the manner in which the anesthetic is delivered (a ‘bolus’ injection of a high quantity, all at once) post-mortem blood samples cannot be a reliable measure of the amount of sodium thiopental that was circulating in the blood.

Another controversial aspect of lethal drug administration is that health professionals are not present during the procedure. Currently, doctors and nurses in the United States are banned by their professional organizations from participating in executions.

The reliability of painless lethal injection procedures will come up when the Supreme Court hears the constitutional challenges specific to the three-chemical protocol. This case, which will be argued early next year and should be decided by early next summer, is in response to an appeal by two Kentucky death row inmates who challenged the execution process. Their argument is based on the belief that the injection of the three-chemical cocktail inflicts unnecessary pain and suffering that could be avoided.


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NocturnalAngell says:

Well lets just say there are times that evidence has been tampered with or omitted, testimony not true, eyewitness accounts not true.. Yes I know the taxpayer pays for the three hots, cot and recreation, but here are instances where the person was executed than found innocent.. What do you do than? What do you say to their family?
1. Cameron Todd Willingham—In 1992, Willingham was convicted of arson murder in Texas. He was believed to have intentionally set a fire that killed his three kids. In 2004, he was put to death. Unfortunately, the Texas Forensic Science Commission later found that the evidence was misinterpreted, and they concluded that none of the evidence used against Willingham was valid. As it turns out, the fire really was accidental.

2. Ruben Cantu—Cantu was 17 at the time the crime he was alleged of committing took place. Cantu was convicted of capital murder, and in 1993, the Texas teen was executed. About 12 years after his death, investigations show that Cantu likely didn’t commit the murder. The lone eyewitness recanted his testimony, and Cantu’s co-defendant later admitted he allowed his friend to be falsely accused. He says Cantu wasn’t even there the night of the murder.

3. Larry Griffin—Griffin was put to death in 1995 for the 1981 murder of Quintin Moss, a Missouri drug dealer. Griffin always maintained his innocence, and now, evidence seems to indicate he was telling the truth. The first police officer on the scene now says the eyewitness account was false, even though the officer supported the claims during the trial. Another eyewitness who was wounded during the attack was never contacted during the trial, and he says Griffin wasn’t present at the crime scene that night.

4. Carlos DeLuna—In 1989, DeLuna was executed for the stabbing of a Texas convenience store clerk. Almost 20 years later, Chicago Tribune uncovered evidence that shows DeLuna was likely innocent. The evidence showed that Carlos Hernandez, a man who even confessed to the murder many times, actually did the crime.

5. David Wayne Spence—Spence was put to death in 1997 for the murder of three teenagers in Texas. He was supposedly hired by a convenience store clerk to kill someone else, but he allegedly killed the wrong people by mistake. The supervising police lieutenant said “I do not think David Spence committed this crime.” The lead homicide detective agreed, saying “My opinion is that David Spence was innocent. Nothing from the investigation ever led us to any evidence that he was involved.”

6. Jesse Tafero—In 1976, Tafero was convicted of murdering a state trooper. He and Sonia Jacobs were both sentenced to death for the crime. The main evidence used to convict them was testimony by someone else who was involved in the crime, ex-convict Walter Rhodes. Rhodes gave this testimony in exchange for a life sentence. In 1990, Tafero was put to death. Two years later, his companion Jacobs was released due to a lack of evidence…the same evidence used to put Tafero to death.

adriano says:

If your gonna go out, u might as well with a smile on ur face. :)
i dont know how they even would let themselves be strapped in like that so easily. Why except death when u can except life :(

L. Crouse says:

On average the people that get the death penalty are people who have done very unspeakable crimes while ruining other peoples lives to better their own! Lethal Injection with antithetic is too good! I say you replace animal testing with the mass murders & rapists that would have rather died in a shoot out! Let them test you products instead, because the animals are still innocent while they are not!
Thanks for reading.

it matters says:

the fact that another human being killed some one and had been proven guilty is enough for me to say he should be executed. if you do not have faith in your law enoforcement or government you can always leave. i actually believe it would be cheaper and easier to use a 50 cent bullet rather than the money it takes for electricty or the chemicals for injection. keeping the murders and criminals in jail cost the tax payers more money, so in reality that criminal is still hurting society and be punished…besides who would want to stay on death row locked up like an animal rather than getting it over with

maggie says:

I agree with one of the commenters here…A MURDERER SHOULD DIE EXACTLY THE WAY HE KILLED HIS VICTIM.

Dante says:

Capital punishment: also referred to as the death penalty, is the judicially ordered execution of a prisoner as a punishment for a serious crime, often called a capital offense or a capital crime.

The Bible and His word are first and foremost important. An eye for eye, tooth for a tooth. That is saying I most hear but what I like to see is “Whoever sheds the blood of man, by man shall his blood be shed.”

In this it’s not those who by accident kill. It’s by those who pre-mediate the murder. Those who can sit there or who can come up with ways, things, to kill or those who kill because they are blind by their hate or their vengeful nature are those considered true murders…I have seen cases where a teen or adult have hit someone with their motor vehicles be convicted of such a heinous crime. But it’s not those people who should be given the death penalty.

Those like McVeigh, Tucker, Vaila, those are the people who should/have the death penalty. Even though Tucker found the Lord before her time was up, it was not within everyone to give her sentence after she converted. But it was said she boasted about the killings, enjoyed doing it. Anyone can fake a conversion. If your life hung in the balance I’m sure anyone could become a Grammy nominee.

The death penalty is not an act of vengeance as most say it is. It is justice handed down by those higher up than yourselves. God in the end makes the final judgement but it is God who says follow the laws of the land. The those laws should be followed. Jesus Christ was an innocent man who was crucified for the sins of others. Those sins that these people (murderers: those who pre-meditate) commit, it’s like slapping Him in the face after everything that he did for us. Why turn your back on His word and His saying?

The death penalty is ONLY a deterrent if applied correctly. If any and all evidence such as DNA, recordings, weapons, etc is found and the person is convicted by using such then they need to get that stamp of approval stamped right on their foreheads just like on their case file. “Death” and should be allowed no more than 3 appeals. Three strikes your out type of deal. Those who are innocent who have the death sentence should be able to find some type of evidence through those 3 appeals. Appeals take time. Their are processes and procedures to go through to get them, to enter them and to see them through. Enough time for those “innocent” convicts to show any evidence of their “innocence”.

I saw in one statement, “What if was your son, daughter, mother or father who was convicted and served the death penalty.” If any of my family members committed such an act to receive the death penalty I would have every major lawyer on the case, every crime PI on the case, everyone I could to get proof of any evidence. Evidence could be used to convict or free anyone responsibility. In the end if none were to prove their innocence I would tell them how much I love them and that I will praying for their soul in the after life and hope that God could grant them mercy that they themselves didn’t show. Just because they are your family doesn’t mean their actions should go unjust.

Those who are victims or are families of those victims who were indeed caught up in the twisted minds of those with no heart, no soul and no back bone, I am truly sorry for your loss(es). To have a family member(s) be taken in a heinous crime would have to truly be hard. And whether some look at the death penalty as a vengeful act, look in the eyes of those who have been apart of something like this. Look into the eyes of a mother who lost her only daughter due to a rapist/murderer. Hell look at your own child, look at their innocent eyes, their unblemished skin, listen to the innocence in their laughter. What if your kid was the victim of something like that, would you too not want vengeance? I sure as hell would. But vengeance isn’t taking someone(s) life through the justice system. Vengeance is taking justice in your hands and delivering. YOU being the judge, jury and executioner.

And the cost of keeping one on death row is ridiculous. Those family members are suffering and nothing can bring back what was taken from them. Imagine, if your husband, wife, daughter, son, mother, father, brother, sister was a victim, is someone took their life, say by chopping them to pieces or by stabbing them repeatedly or just take the worst case scenario for yourself. Would you not think money comes into play here. Medical treatment due to depression. Cost of a funeral, income, debts, etc. those can be taken care of by the money spent on keeping one on death row. It costs 2.2 million to take care of and get rid of a prisoner on death row. There are now 3232 prisoners on death row and 58 prisoners on Federal death row. That’s 3209 all together. And to think 2.2 million is just the cost for the lower inmates on death row. Federal is more extensive, more expensive. All together $7,238,000,000 is used to house, feed, dress and execute those prisoners. When it could be used to help the victims families. Even half of that could help out those families and the other half be put to better use. Anyone here heard of education? Health insurance? Benefits for those who put their lives out there to keep s safe?

Having a parent, grandparent, uncle and two cousins in law enforcement and military, I KNOW they didn’t get HALF the benefits, half the pay that they should. Everyday I pray that mother or uncle doesn’t get killed in the line of duty and it hits closer to home when my mother comes home two days later because she was at a shoot out the whole time. When 3 officers were killed in that shoot out. Or when I hear we are bombing so and so or there is talking of us getting bombed. I think of my cousins then. One a Marine and on the fronts lines. The other a pilot who has to fly into hostel territory. They make what? $40,000-$50,000 in the military. $35,000-$50,000 as a police officer. Please. Every single one of our finest should make way more than that and have better benefits than what they are given.

Some people who talk this and that about death penalty being inhumane, what about the lives they took? What about the little girl who didn’t get to see age 8 because she got raped than strangled to death? Or the police officer who will never see his family again? Or the people who were in the Oklahoma bombing, the Virgina Tech massacre? None of those people get to have a second chance, they are innocent of the wrong doings in others actions.

And no two wrongs don’t make it right. But justice does. Justice is served to those who need it the most. Justice is handed out to those who have been given a second chance. The second chance to be determined by a seat of peers, to be seen or over heard by all. That is their second chance. Whether they make it out with a non guilty is up to those who up hold the law, those who have to be witness and see the wrong doings, those who get to see someone stand without remorse and say they are not guilty when in fact you can see it in their cold, dead, soulless eyes.

Death by injection is the most humane way but it could be better if a health care professional could be the one to set up the IV tubes. There is one in each arm. The first dose is too shut down the nervous system, so that the inmate doesn’t feel a thing. It’s anesthesia is what it is. The next two doses are administered right after the anesthesia is taken affect. The second one is used to cause paralysis and stop breathing. The third is used to stop the heart. Anyone of these used can and will be lethal. So the inmate doesn’t feel, nor is aware of what is happening once they go under. But the sodium thiopental (anesthesia) needs to be properly in place and the right dosage used. Hence me saying they need someone in the health care field to set up the IV tubes. When done right, the party on the receiving end dies painless and none the wiser. They get off a whole lot easier than the victims they killed. So why should anyone feel sorry for them? They committed a crime, they killed someones loved one, they went against the His word…It’s their own fault. It’s their own actions. It’s their own fate.

marisol says:

I think it is true that two wrongs don’t make a right but considering the convicted criminal is there for a reason he should b punished. However my problem is with who gave us the right to take a life? Sure the criminal most likely took a life himself (perhaps many) and for that he can pay by rotting in prison. killing him would take care of the problem but wouldn’t u get more satisfaction from seeing him suffering behind bars? We can always make it interesting schedule monthly tortures, you know some really sadistic shit.

Liana says:

In my opinion, lethal injections is not truly humane! The final heart-stopping drug is not swift enough, and the average of the deaths since the initiation of this method was 8.4 minutes. A lot of painful suffering in the process. I would rather say the guillotine was more humane in the past. You would feel your head decapitated about 3o seconds. The beheading had been more smooth in the guillotine than the skilled executioners own axe. Although, their heads were not completely sliced off, sometimes, which no doubt would be unbearable! Lethal injections are time consuming, but cheaper than the hangings. Death should be easy on prisoners, I believe in righteousness!

Nathan says:

What if they were innocent?

Carmen says:

I live in South Africa and there is no such thing as the death penalty here, which is a shame because the crime here was much lower then, when it was around, than now. We have a high unemployment rate in this country and because of this many are homeless and go hungry. A lot of these people commit murder because they are likely to stay in there because judges and juries are more likely to sentence rapists and murderers than thieves because of over crowding. These people at least know they’ll get 3 meals a day, and a bed to sleep in. There are however the one or two Maximum Security Prisons (like Westville for all you Saffas who know what I’m talking about out there :)) where prisoners beg to die, but most of our prisons are more like 5 star luxury spas.

scatty says:

I have been reading some of these comments and I have to say that I don’t think religion should come into it at all because the cruts of it is if you take a life be it pre meditated or not you should lose yours. The world has gone to pot and why they abolished capital punishment is beyond me! If you are caught stealing in Saudi-Arabia without warning your hands are cut off.
In my Country UK there is only one punishment and that’s imprisonement and even that is all wrong. If you get caught for such horrific crimes ie: murder then you should be given the most humane pubishment via Lethal Injection end of.

Nickelodeon96 says:

So we are telling people we are not allowed to kill people, so we kill people? Yay logic! :D

Anna says:

I don’t care what those people have done, it is not okay to take the life of another person. Lock them up in jail, put them into therapy DON’T KILL THEM! Think about it maybe that person killed one of your loved ones, is that okay? NO! But they have family too and the death penalty will have the same effect on them. On top of that our justice system is far from perfect what if that cold blooded killer turns out to be innocent??? This issue really makes me angry……

Bay says:

Okay. I have read through every comment and everyone has their own opinion. Some say it is murder and others think the inmate deserves it. I believe it is murder and that they deserve it. On a different note….Right now I am writing a debate on this topic. So from all of those who say it is murder if you have information and professional statistics I would appreciate anything and everything.

1Mind says:

I believe that if someone does something wrong to someone else they deserve the same in return, but what most people don’t realize is that the act of killing someone whether they deserve it or not is more harmful to the one doing the killing because it is very disturbing to the mind and that’s why most people who kill are crazy it is not something normal to do. When that is passed down it causes a chain that’s why people will never stop killing it becomes a disease that continues until it is completely eradicated and unfortunately that still hasn’t occurred because the guy who received the death penalty dies but the one who kills him is still alive so that person is still on this earth with his mind all twisted in side. I’m pretty sure no one whose commented on this has ever killed anyone because if you did you wouldn’t be the same person that’s why a lot of soldiers come back from war with all sorts of mental disorders killing someone is really not the answer especially in our society those kinds of acts whether they are legal or not shouldnt be allowed in our society if we expect to grow intellectually.

deez nutz says:

i think no one should be allowed to live past 30 and if you commit a violent crime no matter what it is you should be killed immediately after you are convicted even if all you did was slap you wife. and if we all didnt expect to live long lives we wouldnt have crime period because there would be no time for it and all you would care about is living your life to the fullest instead of having all the bs and drama that causes crime in the first place

livi says:

If it was suggested to throw death row prisoners out of planes to kill them, it would immediately be shouted down as horrible and cruel, right?
But, in essence, it has the same effect as the death penalty.
There would be years of waiting to die, then several minutes (falling out of plane or falling unconscious) of incoming death, and then a quick death (heart stops beating, hitting the ground)
If you cannot, in good conscience, throw a prisoner out of an aeroplane, then you should not give them a lethal injection.

Shy says:

Why do we care so much about “cruel and unusual punishment” on these criminals? Did they spare their victims unnecessary pain and suffering? Did they give them a cocktail of medicines to make sure that they weren’t awake and aware of what was happening to them? Did their victims have 8,10 even 20 years to prepare themselves of the inevitable? No. So, again I ask, who cares? Let them die. Who cares if they feel a little bit of pain while being executed? I’m only sad that they can’t be killed in the same manner as they killed their victims.

Tom says:

At comment number 1 martin jones. Learn how to spell please

Josh says:

At #10, Scott, the bible doesn’t say an eye for an eye. That was Hammurabi’s code. If you are going to quote something at least read it before posting.

xizej says:



up here How does lethal injection work?

Your style is so unique compared to other people
I’ve read stuff from. Thanks for posting when you

sprite says:

Sam I would comment about the other posts and their spelling when you can’t spell either. The word is America not americia.

Pierlando says:

No one can kill, you don’t have the right to decide who can live and who’ve to die. Did you loose someone? A killer killed your family? You’re the same, because I said that no one can kill, instead to kill, the inmate’ve to pass the life in prison, workin hard for the society, understanding what life is. Learn and grove

tishanna says:

No one can kill you!

Kristin says:

I have thought long and hard about the death penalty after reading cases in which new DNA evidence has proven an inmate’s innocence many year after their execution. HOWEVER, I believe very strongly that MORE GUILTY people have been executed. Sociopaths. Men who have – without a single shred of conscious – raped, tortured and murdered children, women – innocent lives! I feel that each predator should die in the same fashion that they committed their crimes. These people have snuffed out the lives of mothers, fathers, sons and daughters. Victims who, with their last breath, saw the faces of these a*#holes! “Humane” treatment should be the furthest thing in anyone’s mind…Were these monsters “humane” when they knowingly took the life of another person?? No.
Our society has become SO “P.C.,” it’s sickening…Hardworking Americans are forced to pay for criminals to live lives in which they receive hot meals, an education (when a huge percentage of college students struggle to obtain a degree due to financial hardships?!) This is what we pay for?! I’m so sick of people crying “unfair!” when it comes to the MANNER in which these people are gotten rid of! These idiots who are SO anti-capital punishment should be the ONLY Americans TAXED and made to pay for the expenses that the prison system soaks out of our pockets! Have a wife/daughter/loved one brutally murdered…THEN tell me how sweetly and kindly you want the SOB who did it to be put to death! Pull the self-righteous stick out of your arse…The law is THERE to protect further innocent Americans from being victimized by these criminals. If your conscious is so heavy, we’ll ship ’em to YOUR house! Good luck with that. You might change your tune after all…

chumiso ngcungca says:

Thanks to god i am a south african where everyone has a fundamental unlimited right to life. Putting out fire with fire will never works as still murders a killing in countries that have a death penalty killing a person is morally wrong. I have lost a father in the hands of criminals but that is not going to turn me into a murder and who am i do dicide that one derserves to die. My opinion death penalty should be abolished in all countries

Mathias says:

Why would you murder a murderer. Because if you do that you only make it worse.i can understand that the family of the one who got murdered is not happy with the one who commited the crime but commiting another murder by murdering the murderer you only make it worse .

Tracy Forman says:

My question is how hard is this really?Why can’t they administer an anesthetic, as if they were going to be in major surgery and then overdose? Then there should be no issue.

Do we think and believe that the three chemical infections used in the lethal injection method form of Capital Punishment given to Juvenille Deliquent Adulthood Criminals with a genetic neuro-chemical pre-disposition could be used effectively as immediate and long lasting relief to severe traumatizing symptoms and behaviors ideal to suicidal and homicidal ideations and activity based on an abusive history of the use of illegal/illicit substances that have mind altering capabilities to the direct point of producing and achieving a noncompliance toward becoming diseased even after brain death occurs could be used as a medical anecdote with scientific evidence to correlate simultaneous and congruent data together to conjugate a unique case study of an individual or group that has or has had an untreatable strand of Bipolar Disorder type I and/or II or irresistible toward any and all forms of variables, transient means, and medical facts to treat a life threatening health concern? Definitely

A. person says:

I live in Canada, where we don’t believe in capital punishment. What if new evidence comes to light, and proves the person in jail is not the killer? Then, you would have let an innocent man die for nothing. If you had not killed him, then you would have been able to set them free, alive, instead of murdering them for a crime they did not commit.

Ed Janison says:

Why can’t they use either a bolus of pure heroin, fentanyl, or carfentanyl? I hear about junkies dying from this stuff with their “works” still in their arm.

Shane Snyder says:

We simply either A. Abolishment the death penalty. Because death is too easy for these criminals anyway. That way, should down the road, an inmate be found innocent, he may still also be found alive. That problem is solved. Next problem, the cost to remand. Well right now in at least one state, maybe more, possession of drugs in any amount is mandatory prison time. Let’s change this and instead of incarcerating these people, we get them into drug rehab programs and hospitals. You’ll save money on the cost of incarcerating them which can be reinvested into jailing these death row inmates for life until they die if natural causes. I know…..death is too good for them but then they get free room and board and tv etc etc? No…….they get nothing but enough food to survive, basically they get just the bare amount of treatment to not be inhumane and they will wish they died. Then the cost of rehabs and hospitals of those drug offenders you paroled? That money pales in comparison to the cost of wrongful death lawsuits for the execution of an innocent man. So that’s an option, abolish the death penalty and when people murder they know they aren’t gonna get the death penalty or anything but life in basically a dog cage with bread and water and miser for a lifetime. They won’t kill anymore. Power perceived is power achieved.

Option 2…..Keep Lethal injection and if the person feels some discomfort……well it was probably it as bad as the discomfort the little girl felt when her body was ripped apart. Only that leaves the possibility of innocent people being executed. So I’d say option 1.

Shane Snyder says:

Hey A.Person from our Liberal friends up North. What do you think about my suggestion or option #1 or A.? It’s my very first suggestion I’d think. Personally if I had my way, I’d spend not a cent more than the cost of one bullet to put in their head and be done accept the innocent theory. So that’s why I say option 1.

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