How Death Penalty Executions Work in the United States

A death penalty execution in the United States is the final step of a long, tightly regulated process that begins with a capital trial, runs through years of mandatory appeals, and ends with a scripted protocol inside a state or federal death chamber. To understand how death penalty executions work in the United States, it helps to follow that sequence in order: who can be sentenced, what appeals must happen before an execution date can hold, which methods are authorized, and what actually takes place on the day itself. Twenty-seven states, the federal government, and the military currently authorize capital punishment; 23 states and Washington, D.C., have abolished it. About 2,090 people were on death row at the start of 2025, and 47 executions were carried out that year, nearly double the 25 recorded the year before.

Who Can Be Sentenced to Death

Almost no crime short of murder qualifies for the death penalty. The Supreme Court held in Coker v. Georgia (1977) that death is a disproportionate punishment for the rape of an adult victim who was not killed,¹ and extended that principle in Kennedy v. Louisiana (2008) to all crimes against individuals that do not result in the victim’s death, including child rape.² In practice, capital punishment is reserved for homicide and a narrow set of crimes against the state such as treason and espionage. Under 18 U.S.C. § 3591, the federal death penalty applies to treason, espionage, and offenses where the defendant intentionally killed, intentionally caused serious injury resulting in death, or knowingly participated in violence creating a grave risk of death; a separate provision reaches leaders of large-scale drug trafficking operations who order killings.³

Even for eligible crimes, a death sentence requires a two-phase trial. After a jury returns a guilty verdict, a separate sentencing phase begins. The prosecution must prove at least one aggravating factor beyond a reasonable doubt before death becomes a legal option. Common aggravators include killing a law enforcement officer, killing multiple victims, murder committed during another serious felony such as robbery or kidnapping, murder for hire, and killings that were especially cruel or premeditated.

The defense answers with mitigating evidence: severe childhood abuse, mental illness, a minor role in the killing, no prior criminal record, youth, remorse. Jurors weigh the two sides using their own judgment rather than a numerical tally. The American Bar Association recommends that capital defense teams include a mitigation specialist who develops the life-history investigation that this stage depends on.

Who Cannot Be Executed

Three categories of people are categorically exempt from execution regardless of the crime.

Anyone who committed the offense before turning 18. Roper v. Simmons (2005) ruled that the diminished culpability of minors makes execution disproportionate, and federal law sets the same floor.⁴³
People with intellectual disabilities. Atkins v. Virginia (2002) held that executing them violates the Eighth Amendment, though states retain some latitude to define the clinical threshold.⁵
People who are mentally incompetent at the time of execution. Ford v. Wainwright (1986) requires that a prisoner be aware of the punishment and understand why it is being imposed; if not, the execution must be delayed until competency is restored, and the prisoner is entitled to a hearing with their own experts.

States may go further than these constitutional minimums by setting broader exclusions or abolishing the practice entirely.

The Years Between Sentence and Execution

A death sentence is closer to the beginning of the legal process than the end. Every person sentenced to death receives an automatic direct appeal to the state’s highest court, or, for federal defendants, to the federal appellate courts. That first appeal reviews the trial record for legal errors in both the guilt and sentencing phases. Several further stages typically follow.

State post-conviction review, where the defendant can raise issues outside the trial record such as newly discovered evidence or ineffective assistance of trial counsel. This stage often involves a separate evidentiary hearing.
Federal habeas corpus, in which the defendant petitions a federal district court claiming the conviction or sentence violated the U.S. Constitution. The judge may dismiss the petition, overturn the conviction, or overturn the sentence. If denied, the defendant must obtain permission from the U.S. Court of Appeals to continue, which is not guaranteed.
U.S. Supreme Court review, which is discretionary. The Court accepts only a handful of capital cases each year. If it declines, judicial appeals are exhausted.

The result is that inmates spend an extraordinarily long time on death row. As of 2020, the average time between sentencing and execution was roughly 19 years, and many inmates die of natural causes before an execution date is ever carried out.⁶

Challenges to the method of execution itself travel through these same courts. Under Glossip v. Gross (2015), a prisoner challenging a particular protocol must show it poses a substantial risk of severe pain compared to a known, available alternative. That burden is heavy, and it has allowed contested protocols, including those using the sedative midazolam, to survive constitutional scrutiny.

Clemency

Once judicial appeals are exhausted, the final avenue is executive clemency. For state prisoners the power usually belongs to the governor, though the process varies. In some states the governor acts alone; in others, the governor cannot grant clemency without a recommendation from an advisory board; in a few, a board makes the decision independent of the governor. For federal prisoners, the President holds sole clemency authority. President Biden used that power near the end of his term to commute the death sentences of 37 of the 40 people then on federal death row.⁷

Methods Used in the Chamber

Lethal injection is the default method in every state and federal jurisdiction that carries out executions. The traditional protocol uses three drugs in sequence. The first is an anesthetic, originally sodium thiopental and now more commonly midazolam, intended to render the person unconscious. The second, typically vecuronium bromide, paralyzes the muscles and stops breathing. The third, potassium chloride, stops the heart. Some states have moved to a single-drug protocol using a large dose of pentobarbital, a powerful sedative that causes death on its own.

Access to the drugs has been the biggest practical obstacle. Starting in 2011, the European Union expanded its export rules to bar the sale of barbiturates and anesthetics used in executions to the United States. The last American manufacturer of sodium thiopental stopped production that year, and pentobarbital’s sole U.S.-licensed manufacturer also cut off sales to prisons. States responded by turning to compounding pharmacies, switching to midazolam, or sourcing pentobarbital through channels they often refuse to disclose. The secrecy itself has generated litigation. A January 2025 executive order directed the Attorney General to help states obtain lethal injection drugs.⁸

Several states authorize alternative methods, usually as backups when drugs are unavailable or when the prisoner elects a different option.

Electrocution remains authorized in a handful of states, where the prisoner is strapped into a chair and subjected to high-voltage current.
Nitrogen hypoxia, which replaces breathable air with pure nitrogen and causes death through oxygen deprivation, has been used by Alabama and adopted by several other states. The Supreme Court has so far declined to block nitrogen executions, though three justices have publicly dissented.
Firing squads are authorized in a few states. Idaho moved the firing squad to its primary method starting in mid-2026.
Lethal gas and hanging remain technically authorized in isolated cases but are rarely if ever used.

What Happens on Execution Day

On the day of a scheduled execution, the process follows a tightly controlled sequence. The inmate is moved from general death row housing to a holding cell adjacent to the execution chamber. This period, often called a death watch, involves constant monitoring by correctional officers. The condemned person is typically offered a final meal, though policies on cost limits and menu options vary widely.

Witnesses gather in a viewing area separated from the chamber by a window or partition. The group usually includes representatives from the prosecution, members of the victim’s family, the inmate’s family or chosen witnesses, and members of the media. Execution team members test equipment, confirm the inmate’s identity, and prepare the delivery system for whatever method has been authorized. For lethal injection, that means establishing intravenous access, which can itself become a prolonged and sometimes medically difficult process.

Legal challenges can arrive up to the final minutes. The warden and government attorneys monitor for court-issued stays throughout the day, and executions are sometimes halted after the prisoner has already been strapped to the gurney. Once final legal clearance is confirmed, the inmate is typically given an opportunity to make a last statement. These statements are generally transcribed by officials rather than recorded, and documentation practices differ across jurisdictions. The warden then gives the order to proceed, the curtain to the witness area is opened, and the execution is carried out.

State, Federal, and Military Tracks

Whether a capital case goes forward in state or federal court depends on where the crime occurred and which laws were broken. A murder that violates only state law is prosecuted by the local district attorney under that state’s capital sentencing scheme. A murder that also violates federal law, such as a killing committed during a bank robbery, drug trafficking operation, or act of terrorism, can be prosecuted federally under 18 U.S.C. § 3591.³

Federal death row inmates have historically been housed at the U.S. Penitentiary in Terre Haute, Indiana, where all modern federal executions have taken place.⁹ The Department of Justice rescinded the Biden-era moratorium on federal executions in April 2026, authorized death sentences against dozens of defendants, directed the Bureau of Prisons to reinstate the execution protocol used during the first Trump administration, and instructed the agency to explore expanding or relocating federal death row and potentially building additional facilities to accommodate methods beyond lethal injection, including the firing squad.⁷

The military operates its own capital punishment system under the Uniform Code of Military Justice, which lists 15 offenses punishable by death, most of them only during wartime. No member of the military has been executed since 1961, and the military death penalty was formally reinstated in 1984. Military cases follow procedures distinct from both state and federal civilian systems.

1
Justia U.S. Supreme Court Center. Coker v Georgia, 433 US 584 (1977)
2
Justia U.S. Supreme Court Center. Kennedy v Louisiana, 554 US 407 (2008)
3
Office of the Law Revision Counsel. 18 USC 3591 – Sentence of Death
4
Justia U.S. Supreme Court Center. Roper v Simmons, 543 US 551 (2005)
5
Justia U.S. Supreme Court Center. Atkins v Virginia, 536 US 304 (2002)
6
Bureau of Justice Statistics. Capital Punishment, 2020 – Statistical Tables
7
U.S. Department of Justice. Justice Department Takes Actions to Strengthen the Federal Death Penalty
8
The White House. Restoring the Death Penalty and Protecting Public Safety
9
Federal Bureau of Prisons. Federal Executions