By: Sarah Pape
Published: June 7, 2025
“I’m leaving with love, peace and light, . . . thank you for supporting me, love all of you.”[1] Those were the last words of inmate Kenneth Smith before the State of Alabama killed him using nitrogen gas in 2024.[2] It took him around thirty-two minutes to die.[3] Nitrogen gas asphyxia, also known as nitrogen hypoxia,[4] is a relatively new form of execution that only a few states have adopted to kill the condemned.[5]
Since 1982,[6] most states have executed those on Death Row through lethal injection,[7] typically in a three-drug protocol: an anesthetic (like sodium thiopental or pentobarbital), a paralytic agent (like pancurium bromide), and finally, a drug to stop the heart (potassium chloride).[8] While many believe that lethal injection is a quiet and humane way to execute a human being, eyewitness accounts say otherwise.[9] In many of these accounts the last thing seen is the inmates taking a large inhale or gasping, a reflex presumably attributed to life leaving their body. The exact reason for this ‘gasping,’ however, was discovered only nine years ago by Drs. Joel Zivot and Mark Edgar of Emory University, when they reviewed autopsy reports of inmates executed by the State of Georgia.[10] Zivot and Edgar found that although the paralytic was administered, the inmates did not die a painless or quiet death, as many believed.[11] Instead, their lungs weighed two to three times the weight of a normal lung and were filled with fluid, indicating pulmonary edema – in other words, they drowned in their own lungs.[12] In recent decades, there has been a push, both in and out of the courtroom,[13] to move away from lethal injection for one large and alarming reason: states keep botching these executions.[14] The reasons for these botched executions vary from untrained executioners,[15] since medical professionals are forbidden from participating in executions,[16] to preexisting medical conditions of the inmates, to states and prisons purchasing expired or ineffective drugs from shady and irreputable sources.[17] In particular, Alabama has such a large rate of botched lethal injections,[18] including Kenneth Smith’s first attempted execution,[19] that Governor Kay Ivey had to implement a temporary execution moratorium while the Alabama Department of Corrections conducted a top-to-bottom review of the state’s capital punishment system.[20]
Some might ask: if states can’t seem to get these executions right, why not challenge it in court? The answer is twofold: countless capital defense attorneys have challenged these practices, and the Supreme Court does not care.[21] In two separate cases, Baze v. Rees and Glossip v. Gross, the Supreme Court established a three-part test, now known as the Baze-Glossip test, to challenge individual executions as being cruel and unusual under the Eighth Amendment.[22] Under this test, an inmate wishing to succeed on an Eighth Amendment method-of-execution claim must establish three things: (1) the execution poses a substantial risk of serious harm, (2) there exists a feasible and readily implemented alternative method, and (3) the state has refused to adopt the available alternative method without a legitimate reason.[23] When a method of execution is already authorized under state law, a party raising an Eighth Amendment claim must show that the method creates an unacceptable risk of pain.[24] As the Baze-Glossip test is the sole means for relief from a barbarous execution and with these issues being raised on the Supreme Court’s stealthy ‘shadow docket,’[25] few of these challenges have ever succeeded. In fact, a method of execution has never been invalidated as entirely unconstitutional under the Eighth Amendment.[26] Given the number of botched lethal injections and the litigation to stop them, many states, first among them Alabama, sought a different method of killing.[27] Enter: nitrogen gas asphyxia.
While the majority of Alabama’s nitrogen gas asphyxia execution protocol remains redacted, what we know about how nitrogen gas asphyxia works is as follows:[28] first, inmates like Kenneth Smith have a mask affixed to their face after being strapped on a gurney in the execution chamber.[29] Inmates are given the chance to say their final words, a subsequent inspection of the death mask occurs, and the execution team leaves the room. After that, the warden activates the nitrogen gas from another room, causing pure nitrogen gas to fill the chamber.[30] The procedure states that the gas will continue to flow for fifteen minutes or five minutes after the inmate flatlines, whichever is longer.[31] Although the oxygen we breathe is 78% nitrogen, the ingestion of pure nitrogen deprives a person of the oxygen needed to maintain organ functioning, and slowly chokes them to death.[32] While Kenneth Smith is one of a few inmates who have died by nitrogen gas asphyxia, the cyanide gas executions of the 20th century shed some light on the physical consequences of gas execution. There was evidence of extreme pain, anxiety, strained breathing, prolonged death, and flash pulmonary edema, a sudden fluid buildup in the lungs.[33] Some of the inmates’ skin turns purple and their eyes pop.[34]
In denying Smith relief, a federal appellate court noted that simply because this type of asphyxia is “new and novel” does not make it inherently cruel and unusual.[35] But the question, which Dr. Joel Zivot puts forward, is “how do we ask an inmate whether or not they experience their own death as cruel?”[36] On a base moral level, drowning someone in their own lungs undoubtedly seems contrary to decency. Nitrogen gas asphyxia, however, also violates the Eighth Amendment – it is just a matter of getting our country’s appellate courts to agree.
First, nitrogen gas asphyxia is “unusual” within the meaning of the Eighth Amendment. Within the Eighth Amendment context, the word “unusual” does not mean rare, but instead, “contrary to long usage” or “new.”[37] Meaning, a punishment is unusual if it is cruel “in light of long usage,” or as compared to longstanding prior practice or tradition.[38] The barbarous and torturous nature of other previous punishments given, in addition to their sparse usage, rendered these methods unusual.[39] No method of execution is as contrary to long usage and “new” as nitrogen hypoxia, given its recent adoption, its lack of testing, and its lack of historical usage.[40] It is because of its novelty that it is unusual.
Second, nitrogen gas asphyxia contravenes Supreme Court precedent acknowledging evolving standards of decency and the dignity of man as the backbone of the Eighth Amendment. In fact, the restrictiveness of the Baze-Glossip test inherently violates these principles by prohibiting consensus and scientific advances from entering the courtroom, effectively green-lighting every method of execution, even barbarous ones.
The underpinnings of the Eighth Amendment are “evolving standards of decency”[41]. In the name of decency, execution by nitrogen gas asphyxia must be considered in violation of the Eighth Amendment’s Cruel and Unusual Punishment Clause. Other sentences have been found unconstitutional,[42] and methods of execution have been phased out to adhere to these evolving standards – it is necessary that nitrogen hypoxia follow suit. The latest nitrogen execution in Alabama occurred on February 7, 2025, when the state executed Demetrius Frazier.[43] His last words were, “Detroit strong. I love everyone on Death Row. Let’s go.”[44]
[1] Aliss Higham, Kenneth Smith’s Final Words Before Alabama Execution, Newsweek (Jan. 26, 2024, 7:06 AM), https://www.newsweek.com/kenneth-smith-final-words-alabama-execution-nitrogen-gas-1864167.
[2] Abigail Brooks, Erik Ortiz & Dasha Burns, Alabama inmate Kenneth Smith put to death in first U.S. nitrogen gas execution, NBC News (Jan. 25, 2024, 10:43 PM), https://www.nbcnews.com/news/us-news/alabama-prepares-first-us-nitrogen-gas-execution-inmate-kenneth-smith-rcna135568.
[3] Questions Surround Execution of Kenneth Smith, Equal Just. Initiative (Jan. 25, 2024), https://eji.org/news/alabama-executes-kenny-smith-using-nitrogen-suffocation/; Ralph Chapoco, Kenneth Eugene Smith executed by nitrogen gas for 1988 murder-for-hire scheme, Ala. Reflector (Jan. 25, 2024, 9:28 PM), https://alabamareflector.com/2024/01/25/kenneth-eugene-smith-executed-by-nitrogen-gas-for-1988-murder-for-hire-scheme/.
[4] Emily Mae Czachor, What is nitrogen hypoxia? Alabama’s Kenneth Smith execution proceeds with unprecedented, controversial method, CBS News (Aug. 20, 2024, 5:05 PM), https://www.cbsnews.com/news/what-is-nitrogen-hypoxia-alabama-execution-kenneth-eugene-smith-death-row-untested-controversial/.
[5] State-by-State Execution Protocols, Death Penalty Info. Ctr., https://deathpenaltyinfo.org/executions/methods-of-execution/state-by-state-execution-protocols.
[6] The History of the Death Penalty: A Timeline, Death Penalty Info. Ctr., https://deathpenaltyinfo.org/stories/history-of-the-death-penalty-timeline.
[7] Total number of executions in the United States from 1976 to 2024, by method of execution, Statista (Aug. 2024), https://www.statista.com/statistics/199086/total-number-of-executions-in-the-us-by-method/.
[8] Overview of Lethal Injection Protocols, Death Penalty Info. Ctr., https://deathpenaltyinfo.org/executions/methods-of-execution/lethal-injection/overview-of-lethal-injection-protocols.
[9] Botched Executions, Death Penalty Info. Ctr., https://deathpenaltyinfo.org/executions/botched-executions; Jessica Miller, Lethal injection: An eyewitness account of Taberon Honie’s execution in Utah, The Salt Lake Trib. (Aug. 13, 2024), https://www.moabtimes.com/articles/lethal-injection-an-eyewitness-account-of-taberon-honies-execution-in-utah/; Scott McIntosh, I was a witness at Thomas Creech’s scheduled execution in Idaho. Here’s what I saw, Idaho Statesman (Mar. 25, 2024, 10:32 PM), https://www.idahostatesman.com/opinion/opn-columns-blogs/article286048746.html; Lethal Injections Cause Suffocation and Severe Pain, Autopsies Show, Equal Just. Initiative (Sept. 22, 2020), https://eji.org/news/lethal-injections-cause-suffocation-and-severe-pain-autopsies-show/.
[10] Noah Caldwell, NPR Probe: The Troubling Effects of Lethal Injection, NPR (Sept. 21, 2020, 5:01 AM), https://www.npr.org/2020/09/21/915171183/npr-probe-the-troubling-effects-of-lethal-injection.
[11] Id.
[12] Noah Caldwell, Ailsa Chang & Jolie Myers, Gasping for Air: Autopsies Reveal Troubling Effects of Lethal Injection, NPR (Sept. 21, 2020, 7:00 AM), https://www.npr.org/2020/09/21/793177589/gasping-for-air-autopsies-reveal-troubling-effects-of-lethal-injection (noting that in a review of more than 200 autopsies, pulmonary edema was found in 84% of the bodies of those executed).
[13] Lethal Injection Cases, Death Penalty Info. Ctr., https://deathpenaltyinfo.org/stories/lethal-injection-cases.
[14] Botched Executions, supra note 9; Chiara Eisner, States botched more executions of Black prisoners. Experts think they know why, NPR (Apr. 18, 2024, 5:00 AM), https://www.npr.org/2024/04/18/1245290751/botched-exections-black-race-death-penalty; Crystal Ponti, Botched Executions: Infamous Examples of Trouble on Death Row, A&E (Jan. 25, 2024), https://www.aetv.com/real-crime/botched-executions.
[15] Stephanie Mencimer, State Executioners: Untrained, Incompetent, and “Complete Idiots”, Mother Jones (May 7, 2014), https://www.motherjones.com/politics/2014/05/death-penalty-lethal-injections-untrained-doctors/; Effort to Kill Ohio Inmate Postponed After Botched Execution Attempt, Equal Just. Initiative, https://eji.org/news/ohio-botches-execution-of-romell-broom/.
[16] Jordan Price, Humanitarian Concerns About Methods of Education, UAB Inst. for Hum. Rts. Blog (Nov. 20, 2023), https://sites.uab.edu/humanrights/tag/lethal-injection/#:~:text=As%20outlined%20in%20the%20Hippocratic,who%20are%20not%20trained%20in; Physician Participation in Executions, Inst. of Clinical Bioethics, https://www.sju.edu/centers/icb/blog/physician-participation-in-executions#:~:text=Physician%20participation%20in%20executions%20is,beneficence%2C%20nonmaleficence%2C%20and%20justice.&text=%5Bi%5D%20Council%20of%20Ethical%20and,18.
[17] Tanya Greene, The Shadow Economy of Lethal Injection Drug Deals, ACLU (Aug. 4, 2014), https://www.aclu.org/news/capital-punishment/shadow-economy-lethal-injection-drug-deals; Arizona DoC Paid $1.5 Million for Execution Drugs While Facing a Budget Crisis, Death Penalty Info. Ctr. (Apr. 15, 2021), https://deathpenaltyinfo.org/arizona-doc-paid-1-5-million-for-execution-drugs-while-facing-a-budget-shortfall; Investigative Report: Idaho Records Reveal State’s Efforts to Conceal Ghost Purchase of Execution Drugs and Out-of-State Cash Payment to Pharmacy With Dubious Regulatory History, Death Penalty Info. Ctr. (Jan. 21, 2022), https://deathpenaltyinfo.org/investigative-report-idaho-records-reveal-states-efforts-to-conceal-ghost-purchase-of-execution-drugs-and-out-of-state-cash-payment-to-pharmacy-with-dubious-regulatory-history; Ed Pilkington, Death penalty states illegally imported drugs for executions despite warnings, The Guardian (Oct. 23, 2025, 4:25 PM), https://www.theguardian.com/us-news/2015/oct/23/death-penalty-states-drugs-illegal-sodium-thiopental.
[18] Alabama’s Recent Botched Executions and Execution Attempts, Equal Just. Initiative (Jan. 25, 2024), https://eji.org/issues/alabama-botched-executions/; Alexandra L. Klein, The 2022 Alabama Executions and the Crisis of American Capital Punishment, 24 Nev. L. Rev. 1, 3 (2023) (noting that in 2022, Alabama botched three of the four executions it tried and called off two).
[19] Kenneth Smith Describes Alabama’s Failed Attempt to Execute Him, Death Penalty Info. Ctr. (Jan. 18, 2023), https://deathpenaltyinfo.org/kenneth-smith-describes-alabamas-failed-attempt-to-execute-him; Kim Chandler & Jay Reeves, Alabama fails to complete lethal injection for 3rd time, AP News (Nov. 18, 2022, 11:00 PM), https://apnews.com/article/alabama-executions-457bf774ac634d868693f905a45e50dd.
[20] Jay Reeves, Alabama pausing executions after 3rd failed lethal injection, AP News (Nov. 21, 2022, 3:16 PM), https://apnews.com/article/alabama-executions-kay-ivey-fd61fdbef131c192958758ae43a8c34a.
[21] See, e.g., Baze v. Rees, 553 U.S. 55, 77, 94-107 (2008) (Thomas, J., concurring) (electing to invalidate a given method under the Eighth Amendment only if it is deliberately designed to inflict pain).
[22] Bucklew v. Precythe, 587 U.S. 119, 130 (2019) (explaining that Baze and Glossip govern all Eighth Amendment challenges, whether facial or as-applied).
[23] Baze, 553 U.S. at 50 (establishing that an execution method must present a substantial or objectively intolerable risk of serious harm, and the state must have a legitimate penological reason for refusal); Glossip v. Gross, 576 U.S. 863, 878 (2015) (holding that prisoners cannot challenge a state’s method just by showing a slightly safer alternative).
[24] Glossip, 576 U.S. at 884 (rejecting Petitioner’s method-of-execution lethal injection claim in part because testimony supported the conclusion that the lethal injection drug rendered a person insensate to pain).
[25] Supreme Court’s “Shadow Docket” Shapes Death Penalty Litigation, A.B.A. (Jan. 25, 2021), https://www.americanbar.org/groups/committees/death_penalty_representation/project_press/2020/year-end-2020/the-influence-of-the-shadow-docket-on-death-penalty-litigation/.
[26] Glossip, 576 U.S. at 869 (noting that the Court has never held a State’s chosen procedure to inflict cruel and unusual punishment).
[27] Erik Ortiz & Abigail Brooks, Alabama executes inmate with nitrogen gas after past lethal injection attempt failed, NBC News (Sept. 26, 2024, 8:35 PM), https://www.nbcnews.com/news/us-news/alabama-prepares-put-inmate-death-second-us-nitrogen-gas-execution-rcna172254.
[28] Kim Chandler, Alabama describes proposed nitrogen gas execution; seeks to become first state to carry it out, AP News (Aug. 29, 2023, 5:09 PM), https://apnews.com/article/death-penalty-alabama-nitrogen-hypoxia-3aa41ad4da3f719e9f06425798e1c6a5.
[29] Id.
[30] Id.
[31] Id. (noting that the protocol requires the nitrogen gas to flow for fifteen minutes or five minutes following an EKG flatline, whichever comes last).
[32] Dana G. Smith, Nitrogen Execution Method Touted as More ‘Humane,’ but Evidence is Lacking, Sci. Am. (Sept. 23, 2022), https://www.scientificamerican.com/article/new-execution-method-touted-as-more-humane-but-evidence-is-lacking/ (explaining that the name nitrogen hypoxia is un-scientific).
[33] Caldwell, Chang & Myers, supra note 12.
[34] History.com Eds., First execution by lethal gas, Hist. (July 21, 2010), https://www.history.com/this-day-in-history/first-execution-by-lethal-gas; Jacob Weisberg, This Is Your Death, New Republic (July 1, 1991) (recalling that a warden saw evidence of inmates drooling as their eyes bulged and skin turned colors).
[35] Brooks, Ortiz & Burns, supra note 2.
[36] Caldwell, Chang & Myers, supra note 12.
[37] See, e.g., Trop v. Dulles, 356 U.S. 86, 100-01 n.32 (noting that denationalization as punishment is unusual as it was not explicitly sanctioned until 1940 and had never been previously tested constitutionally).
[38] Id.; Wilkerson v. Utah, 99 U.S. 130, 134-35 (1878) (noting that unusual punishments are outlawed by the Constitution and that shooting as a sentence for first-degree murder is not one of those outlawed punishments as death by shooting is regularly used and approved of for the crime of desertion and other capital military offenses).
[39] Wilkerson, 99 U.S. at 135 (noting that punishments of being drawn and quartered, live disembowelment, beheading, and immolation were unusual as they were seldom strictly carried into effect).
[40] In re Ohio Execution Protocol Litig., No. 2:11-cv-1016, 2023 U.S. Dist. LEXIS 181944 (S.D. Ohio Oct. 10, 2023) (recalling previous methods of execution rendered cruel and unusual as being long disused).
[41] Weems v. United States, 217 U.S. 349, 378 (1910) (explaining that the Eighth Amendment acquires meaning as public opinion is enlightened by a humane justice); Trop, 356 U.S. at 110 (explaining that the Eighth Amendment draws its meaning from evolving standards of decency that mark the progress of a maturing society).
[42] See e.g. Kennedy v. Louisiana., 554 U.S. 407, 421 (2008) (finding national consensus against capital punishment for the crime of child rape in finding it unconstitutional under the Eighth and Fourteenth Amendments); Coker v. Georgia, 433 U.S. 584, 592 (19744) (holding that capital punishment for a nonhomicide rape offense violates the Eighth Amendment); Atkins v. Virginia, 536 U.S. 304, 321 (2002) (holding that the death penalty for the mentally disabled violates the Eighth Amendment).
[43] Alabama Executes Demetrius Frazier, Equal Just. Initiative (Feb. 6, 2025), https://eji.org/news/demetrius-frazier-alabama-execution/; Alabama puts man to death for a 1991 murder in the nation’s fourth execution using nitrogen gas, CNN (Feb. 7, 2025, 2:45 AM), https://www.cnn.com/2025/02/07/us/alabama-execution-demetrius-frazier/index.html.
[44] Richard Pollina, Alabama death row inmate Demetrius Frazier’s final words revealed as he’s executed for 1991 murder, N.Y. Post (Feb. 7, 2025, 4:31 AM), https://nypost.com/2025/02/07/us-news/alabama-death-row-inmate-demetrius-fraziers-final-words-revealed-as-hes-executed-for-1991-murder/.