Doyle Lee Hamm survived his date with the executioner Thursday, as Alabama was unable to begin the procedure before the death warrant expired at midnight.

It was after 11:30 p.m. when word came that the execution had been called off. Alabama Department of Corrections Commissioner Jeff Dunn said medical personnel had advised officials that there wasn't enough time to ensure that the execution could be conducted in a humane manner. However, Dunn declined to detail the exact medical factors behind the decision, and said he didn't want to characterize them as a problem.

Hamm, 61, was convicted of killing Cullman hotel clerk Patrick Cunningham in January 1987. Recent appeals in his case involved the question of whether cancer had left him healthy enough to be executed without excessive suffering. His advocates had argued that his veins were in such bad shape that it wouldn't be possible for the state to carry out its lethal injection protocol cleanly.

One of Hamm's attorneys, Bernard Harcourt, was among those waiting outside death row at Holman Correctional Facility near Atmore. Afterward, via Twitter, he speculated that "they probably couldn't find a vein and had been poking him for over 2 1/2 hours."

Dunn avoided any detailed description of the actions taken by prison medical personnel between 9 p.m., when a temporary stay was lifted, and about 11:15 p.m., when they recommended the execution not proceed. He said only that they felt they would be unable to have Hamm ready by midnight. The state's protocol "has a lot of moving parts," Dunn said.

The commissioner said that Hamm had been returned to a holding cell and would receive another medical exam in the morning, which he described as standard procedure. For another execution attempt to proceed, the state's Supreme Court would have to assign a new date.

Asked if the issues that had thwarted Thursday's attempt would be likely to prevent another, Dunn said, "I wouldn't necessarily characterize what we had tonight as a problem. I don't have any indication at this point that that in fact is the case. The only indication I have is that in their medical judgement it was more of a time issue, given the late hour."

Thursday night's execution originally was set for 6 p.m. A temporary stay from the U.S. Supreme Court was lifted at about 9 p.m., leaving the state clear to proceed. But from that point, things moved slowly. It was 10 p.m. before media observers and other witnesses were transferred to Holman Correctional Facility.

Once on site, they were kept in vehicles outside the actual death row facilities. Such waits are not unusual, but this one lasted well over an hour. Shortly before 11:30 p.m., Department of Corrections officials and guards could be seen conferring, though it was not immediately clear what was happening.

There's a recent precedent for late executions: That of Tommy Arthur, in May 2017, began only a few minutes before midnight, the time when Alabama's death warrants expire. Arthur's time of death actually was after midnight, but the warrants only specify that the process must begin before midnight.

Shortly after 11:30 p.m., officials began to ferry witnesses away from the prison. Reporters were told the execution had been called off because there was insufficient time to prepare.

Harcourt, now a professor of law at Columbia University, has represented Hamm since 1990. Among other efforts, he worked to illustrate extenuating factors in Hamm's life and alleged flaws in the prosecution.

A 2016 New Yorker article drew on Harcourt's research for a chilling summary of Hamm's early life: "Hamm grew up in northwest Alabama, the tenth of twelve children; his father worked as a carpenter and cotton picker, made his own moonshine, drank every day, beat his children with a switch, and was a frequent resident of the county jail (on charges of public drunkenness). Hamm's sister later described their childhood home as 'constant hell all the time.' She also recalled their father telling the children, 'If you don't go out and steal, then you're not a Hamm.' Growing up, Hamm flunked first grade, drank beer and whiskey mixed together, graduated to sniffing glue several times a day, quit school in the ninth grade, ingested Valium and Percocet and Quaaludes, watched his six older brothers all go to jail, and eventually acquired his own extensive rap sheet, including arrests for burglary, assault, and grand larceny."

Despite Harcourt's prolonged efforts, which have been the subject of criticism from at least one judge and the Alabama attorney general's office, in 2016 the U.S. Supreme Court refused to review the case. In December, the Alabama Supreme Court set a date for his execution.

By then Hamm had received partial treatment for cancer first diagnosed in 2014. The Alabama Attorney General's office has argued that the cancer is in remission. Hamm's supporters have said there are signs that it has returned and has caused his health to deteriorate to the point where his veins can't sustain the lethal injection process.

In 2018, the case bounced back and forth between Judge Karon O. Bowdre, U.S. Chief District Judge for the Northern District of Alabama, and the 11th Circuit Court of Appeals. In late January Bowdre granted a stay. The appeals court ruled she had gone too far in basing the stay on "a substantial likelihood of success" with an appeal. The correct standard, it said, was that a "significant possibility of success on the merits" was needed for a stay.

On Tuesday, Bowdre issued an order saying the execution could proceed, provided the state used veins in Hamm's lower extremities and did not attempt to use veins in his arms. Harcourt appealed that ruling; on Thursday, the 11th Circuit Court of Appeals upheld Bowdre's order.

"We conclude that the district court (Bowdre) did not abuse its discretion when it ruled that Hamm cannot show a significant likelihood that execution by intravenous injection would violate his Eighth Amendment rights," the 11th Circuit stated in its ruling to affirm Bowdre's order. "Hamm has two peripheral veins accessible for a lethal injection, and his central veins are likewise accessible for a lethal injection. Finally, the conditions rendering the central veins accessible in Hamm's case--the availability of ultrasound equipment and an advanced practitioner--exist here."

Thursday afternoon, Harcourt again asked the U.S. Supreme Court to consider the case and to grant a stay. The Alabama attorney general's office filed a response asking the court to reject that request, saying an independent medical examiner's report showed that, contrary to claims made on Hamm's behalf, the veins in his legs were suitable and his medical condition presented no obstacles to execution in "a constitutional fashion."

Hamm was one of three men scheduled to die Thursday evening in the U.S. At about 5:30 p.m., The Associated Press reported that Texas Gov. Greg Abbott had spared the life of Thomas "Bart" Whitaker, commuting his sentence to life without parole. Less than an hour later, it confirmed that Florida had executed Eric Scott Branch shortly after 7 p.m. Eastern time.

In between those two developments, word reached Atmore that the U.S. Supreme Court had issued a temporary stay in Hamm's case, putting the execution. The stay was lifted about three hours later, shortly before 9 p.m., with the Supreme Court deciding not to intervene.

Justices Ruth Bader Ginsburg and Sonia Sotomayor dissented from the decision to lift the stay and to avoid a review of the case. Justice Stephen Breyer's position was that he would prefer to reconsider the constitutionality of the death penalty itself rather than develop a "constitutional jurisprudence that focuses upon the special circumstances of the aged," but respected the majority decision to lift the stay.

According to information on the Alabama Department of Corrections website, as of Thursday afternoon the state had 182 inmates on death row. Their average age was 32.

Of the 182, only five were women. The state classed 93 as black, 86 as white and three as "other."

Background on the case of Dole Lee Hamm:

Several groups wrote to Gov. Kay Ivey asking her to grant clemency for Hamm.

The slaying

According to court records, here's what happened the Saturday Cunningham was killed:

At approximately 10:30 p.m., a woman who was traveling from Florida stopped at Anderson's Motel to rent a room. While at the front counter, the woman saw a white male enter the lobby and ask Cunningham about a room for three. Cunningham told the man he needed to have a reservation, and the man left.

As she was leaving the lobby minutes later, the man came back with another white man. Cunningham told the woman, "[It] looks like there is going to be trouble," and he quickly pointed her to her room.

When the woman walked outside and got back in her car, she looked back inside the lobby and saw the second man pointing a "shiny-looking revolver" at the reception desk where Cunningham had been standing. She saw the first man standing near the door and a "banged up" car parked just outside.

She quickly drove to a phone booth and called police, telling the dispatcher the motel was being robbed. She met police at the scene, and described what she saw.

Cunningham's body was found on the floor behind the reception desk. He had been shot in the head with a .38-caliber pistol. Evidence showed Cunningham was lying on the floor when he was shot in the temple, from a distance of approximately 18 inches. Police also said the victim's wallet -- which his wife said had about $60 -- and the motel cash drawer -- which should have had over $350 -- was missing.

After his arrest, Hamm denied any involvement in the killing. Court records show the day after he was arrested, however, Hamm admitted to the robbery and murder.

He did not testify at either his trial or sentencing, and his two co-defendants received lesser charges for testifying against him.

His execution date was set in December by the Alabama Supreme Court.

In the courts

Earlier this month, Bowdre issued a stay of execution after a hearing with attorneys from both parties. Days later, the 11th Circuit Court of Appeals granted the state's emergency motion to vacate Hamm's stay. The appeals court ordered Bowdre to appoint an independent medical examiner to evaluate Hamm's condition. That evaluation was done Feb. 15, and the results were revealed in Bowdre's order Tuesday.

Doyle Lee Hamm before his conviction in 1987. He is scheduled to be executed on Feb. 22, 2018, at 6 p.m. (Contributed)

The medical evaluation showed the veins in Hamm's arms and hands are hard to access, but veins in his legs and feet should be easily accessible for the DOC to insert the catheter needed for the execution drugs. Bowdre stated in her order the state agreed to only use drugs in Hamm's lower extremities.

According to information discussed in hearings and through court records, Hamm was diagnosed with cancer in 2014 and underwent treatment. The DOC said Hamm's cancer went into remission in March 2016, and no scans from an oncologist have been performed since. In spring 2017, Hamm complained of lumps on his chest and abdomen area. An X-ray was performed, but no PET scans or biopsies were completed. Earlier this month, doctors said there was no evidence of cancer in his clavicle, but they did not have a definitive answer about the other lumps.

Hamm's longtime attorney, Columbia law professor Bernard Harcourt, has said Hamm's cancer and subsequent treatments have made his veins inaccessible and unable to handle the catheter. He has referenced affidavits from Department of Corrections nurses who say they have had to "stick" Hamm several times before being able to draw blood.

Assistant AG Thomas Govan argued in court that there is no evidence Hamm's veins are significantly smaller or more difficult to access than they were several years ago. He also said, even if Hamm's chest and abdomen lumps are cancerous, they would not affect his veins.

Following Bowdre's order about the state's agreement to use only lower veins, Harcourt filed a petition to the 11th Circuit Court of Appeals. The appeals court ordered the state to provide affidavits from those who will be involved in Thursday's execution to guarantee the IV procedure agreement, and the state provided one from the prison's warden.

Because of a federal court decision requiring an inmate to suggest an alternative method of execution, Harcourt has said Hamm should be killed via oral injection. The AG's office argued its drug protocol, which includes the sedative midazolam, cannot be used for oral injections.

AL.com reporter Ivana Hrynkiw contributed extensively to this report.