Christa Pike, a Tennessee woman who was set to be executed on Wednesday, survived two doses of a lethal drug that had been administered, according to her lawyers.

Ms. Pike, who was convicted of the 1995 murder of a classmate, is the only woman on death row in Tennessee. Before the failed attempt to put her to death, she was set to become the first woman to be executed in the state in more than 200 years.

Ms. Pike was in “critical condition, receiving life-saving care” on Thursday afternoon, one of her lawyers said.

Here’s what to know:

The Case

In 1996, a jury found Ms. Pike guilty of torturing and murdering a classmate, Colleen Slemmer, in an attack that she carried out with her boyfriend and a friend. They slashed Ms. Slemmer with a box cutter, carved a pentagram into her chest and removed a piece of her skull.

Ms. Pike, who was 18 at the time of the killing, received the death penalty. Her boyfriend, Tadaryl Shipp, was 17 at the time of the crime and was sentenced to life in prison, as he was too young to be eligible for capital punishment in Tennessee.

Ms. Pike, now 50, does not deny her guilt.

“I run through this execution every day in my heart,” she told The New York Times in September. “Whatever happens on Sept. 30, this will not be my hell anymore.”

Some experts have questioned whether Ms. Pike would receive the same sentence if she were to be tried today. Her lawyers argued that Ms. Pike’s initial legal defense did not adequately present her history of child sexual abuse and neglect.

She was later diagnosed with bipolar disorder and post-traumatic stress disorder, which her lawyers said contributed to her mental state during the murder.

“Christa Pike would likely not be sentenced to death if she were tried today,” said Robin Maher, the executive director of the Death Penalty Information Center. “A lot has changed.”

The Victim

Ms. Slemmer, 19, was living hundreds of miles from her family home in Florida when she was killed, having enrolled in a Job Corps educational program in Knoxville, Tenn., to pursue an interest in computers.

She had volunteered at the Special Olympics and loved bowling and computer games, according to her mother, May Martinez.

On the night she was killed, Ms. Slemmer tried to call her mother. The call quickly ended because of a shaky phone signal. When Ms. Martinez called back, her daughter “was already gone,” she said.

Ms. Slemmer’s family has remained firmly in support of Ms. Pike’s sentence, and Ms. Slemmer’s mother is adamant that Ms. Pike could not atone for the murder and should be executed.

“Nobody could ever, ever convince me she’s changed,” Ms. Martinez told The Times.

The Legal Battle

Ms. Pike’s lawyers have tried to stop the execution in recent weeks, arguing that she could support other women in prison and that her crime could not be separated from her traumatic childhood.

They also questioned whether lethal drugs could be administered without causing her excessive pain. In an appeal to the Supreme Court to pause the execution, Ms. Pike’s lawyers argued that the execution was causing her “unnecessary agony” and that it violated the Eighth Amendment’s ban on cruel and unusual punishment.

Gov. Bill Lee of Tennessee, a Republican, said on Monday that he would not intervene to allow Ms. Pike to serve the remainder of her life in prison.

On Wednesday, a federal appeals court briefly paused the execution and said more time was needed to consider the case. After a delay of about nine hours, the Supreme Court allowed the execution to proceed, and the state raced to go ahead with it before the day ended and to avoid having to reschedule.

The court’s three liberal justices dissented from the order allowing the execution. Justice Sonia Sotomayor wrote that the majority “unnecessarily prevents” the appeals court from fully considering Ms. Pike’s argument.

The Botched Execution

It was not immediately clear what went wrong with the administration of the lethal drug on Wednesday night.

Ms. Pike’s lawyers said that while two syringes of pentobarbital had been administered, she did not lose consciousness. She still had a heartbeat, they said, and was audibly snoring.

Reporters who witnessed the execution attempt described Ms. Pike as somewhat alert. Although the curtains separating the execution chamber from the witnesses were closed for nearly an hour after the attempt, reporters said they could still hear breathing and steady snoring.

The Tennessee Department of Correction later said Ms. Pike had been taken to an off-site medical facility.

This was the second time this year that Tennessee had struggled to administer a lethal injection. In May, the state called off an execution because staff members could not find a vein to administer lethal drugs.

The Fallout

After the bungled attempt to execute Ms. Pike, Governor Lee paused capital punishment in Tennessee and called for a review of the state’s policies on how it puts people to death.

It was the second time in five years that Mr. Lee, a Republican, has paused executions because of questions over the effectiveness of the state’s lethal injections. In 2022, he ordered a review after prison officials failed to properly test the drugs before an execution.

In at least one instance, a botched execution has led, effectively, to a reduced punishment.

In Alabama in 2018, an execution team struggled for nearly three hours to locate a vein in Doyle Hamm, injuring several of his organs before giving up. The state then entered into a confidential legal settlement, leaving Mr. Hamm in prison without parole. Mr. Hamm died of cancer three years later.

However, states are far more likely to use administrative holds, revise their methods, or proceed through courts before trying again to execute.

Emily Cochrane, Ann E. Marimow and Adeel Hassan contributed reporting.