Clayton Lockett, the death-row inmate who was the subject of a botched execution by the state of Oklahoma, was Tasered by prison staff and had cut his own arm on the day of the failed procedure, according to a timeline released by the state's corrections chief on Thursday.

The document released by the director of the corrections department, Robert Patton, shows that medical staff could not find a suitable vein on any of his limbs in which to inject the lethal drugs intended to kill him, and had to use his groin instead. Lockett died, apparently from a heart attack, 43 minutes after his attempted execution began and 10 minutes after it had been called off.



Patton recommended an indefinite stay of executions in Oklahoma until procedures for judicial killings in the state are completely rewritten and staff retrained. The execution of another inmate, Charles Warner, also due to have been carried out on Tuesday, has already been postponed.



“It will take several days or possibly weeks to refine the new protocols,” Patton wrote in a letter to the Republican governor of Oklahoma, Mary Fallin. “Once written, staff will require extensive training and understanding of new protocols before an execution can be scheduled. I recommend asking the court of criminal appeals to issue an indefinite stay of execution.” Patton said he supported an “external investigation” of Lockett's death.

Fallin said on Thursday that she had the authority to grant a 60-day moratorium before the attorney general would petition the appeals court for an extension. “We need to take as long as possible to get the answer right,” she told reporters.

Alex Weintz, a spokesman for Fallin, said the state “will not proceed with any executions until department of corrections protocols can be reviewed and updated, and staff then trained to implement those new protocols.”

The timeline published by Oklahoma details a chaotic scene in the death chamber before and during the failed execution, as staff struggle to place an intravenous line into Lockett, report that he was unconscious, but then did not spot that the IV connection had failed because they had covered Lockett groin with a sheet, to prevent that area of his body from being seen by witnesses.



The document is notable as much for what it leaves out as for what it reveals: there is no mention of the three minutes in which witnesses saw Lockett thrashing violently on the gurney and attempting to speak, despite having been declared unconscious. Neither does it say anything about what happened in the ten minutes between the procedure being called off and the moment Lockett died.

Lawyers, state officials and journalists from media groups including the Guardian witnessed the first 16 minutes of the attempted execution before officials drew the blinds that separated the viewing room from the death chamber. For the final three visible minutes, Lockett writhed, groaned, attempted to lift himself off the gurney and tried to speak, despite a doctor having declared him unconscious.

Oklahoma corrections director Robert Patton addresses the media about the execution of Clayton Lockett. Photograph: John Clanton/AP

Lockett was convicted in 2000 and sentenced to death for the kidnap and murder of a 19-year-old, Stephanie Neiman, during a home invasion the previous year. She survived the initial assault, and Lockett ordered two accomplices to bury her alive. He also raped one of her friends. His accomplices are serving life sentences.



Neiman had graduated from high school only two weeks before her death. Her parents, Steve and Susie Neiman, supported Lockett's sentence. After his death on Tuesday, the Neimans issued a statement, saying: “We are thankful this day has finally arrived and justice will finally be served.”



The timeline released by Patton shows that just after 5am on Tuesday, Lockett had refused to be restrained when officers arrived to take him for X-rays. A correctional emergency response team (Cert) was called to use force on him, and he was Tasered at 5.50am. Three minutes later he was found to have a self-inflicted cut on his arm. At 8.15am, the wound was determined not to be serious enough to require sutures.



Oklahoma's timeline also goes into detail about what happened before and during the attempted execution. At 5.22pm, Lockett was restrained on the execution table, but a suitable vein could not be found anywhere on his body in which to insert an intravenous line. Veins on his legs and arms were rejected before a doctor examined his neck, and then finally his groin.

The timeline reveals that the insertion point was covered by a sheet “to prevent witness viewing of the groin area”. The execution began at 6.23pm with the injection of the first of a cocktail of three drugs, but the intravenous line – covered by the sheet – was only checked after 6.44pm, when the blinds between the execution chamber and the viewing room were lowered.

The report says: “The doctor checked the IV and reported the blood vein had collapsed, and the drugs had either absorbed into tissue, leaked out or both. The warden immediately contacted the director by phone and reported the information to the director.”

According to the timeline, Patton asked if enough drugs had been administered to cause death, to which the doctor replied “no”. The director then asked if another vein was available to complete the execution, and if so, were there enough drugs left. The doctor answered no to both questions, the timeline reveals.

The doctor reported a “faint heartbeat”, and at 6.56pm, Patton called off the execution. The timeline does not detail what happened between then and 7.06pm, when Lockett was declared dead.

At an open meeting of the board of corrections on Thursday, Patton refused to answer a question from the Guardian about whether any attempts were made to revive Lockett, and walked out of the room.

Fallin was asked later whether she believed that what happened to Lockett was constitutional. “That will be answered by the courts and by those that are in authority,” the governor said, adding that she did not know if any attempts had been made to resuscitate Lockett after the execution was called off.

Oklahoma governor Mary Fallin. Photograph: Sue Ogrocki/AP

Attorneys for Lockett and Warner had challenged Oklahoma's secrecy about the source of death penalty drugs, which is permitted under a state law enacted in 2011. The state used a cocktail of drugs in Tuesday's procedure in dosages that were untested in American executions. But the timeline appears to indicate that problems with the execution could be attributed to the failure even to inject the drugs properly.

Madeline Cohen, a lawyer for Warner, the second of the two inmates due to have been put to death on Tuesday, agreed with Patton's conclusion that an indefinite suspension of executions was necessary.

“As the Oklahoma department of corrections dribbles out piecemeal information about Clayton Lockett's botched execution, they have revealed that Mr Lockett was killed using an invasive and painful method – an IV line in his groin,” she said. “Placing such a femoral IV line requires highly specialised medical training and expertise.

“Furthermore, the timeline the department of corrections has released strongly indicates that the femoral IV was never properly inserted, and the drugs were injected into Mr Lockett's flesh, rather than his veins,” she said.

Specialists expressed particular alarm that the final minutes of the attempted execution were obscured from public view. “It’s abysmal that they had the gall to close the curtains at a time when transparency was essential,” said one expert familiar with drugs used in Oklahoma’s botched execution of Lockett, who declined to be named. “That’s when witnesses were most needed to report back what happened to the rest of the country.”



The expert said that it should have been possible to save Lockett’s life once the execution had been called off and even after the drugs had been administered. Medics could have very likely saved Lockett by deploying a breathing tube, placing him on a ventilator, and applying tourniquets to his arms to prevent the drugs reaching his heart, the specialist said.

Cohen expressed concern about the failure by the timeline released on Thursday to account for what happened in the ten minutes between the suspension of Lockett's execution and his death. “We need so many answers,” she said

On Wednesday, Fallin directed the Oklahoma department of public safety to review what happened to Lockett. Lockett's body was moved overnight to the Southwestern Institute for Forensic Science in Dallas, which will carry out a postmortem examination.



Lockett's attorneys expressed doubt that the review would be independent. The commissioner of the department of public safety, Michael Thompson, is a Fallin appointee and was in the execution viewing room on Tuesday night. Fallin “did not assign this duty to a neutral, third party with independent interests”, said Dean Sanderford, an attorney for Lockett.



“Instead, she has charged the commissioner of the department of public safety with the job. The DPS is a state agency, and its commissioner reports to the governor. As such, the review proposed by governor Fallin would not be conducted by a neutral, independent entity. In order to understand exactly what went wrong in [Tuesday’s] horrific execution, and restore any confidence in the execution process, the death of Clayton Lockett must be investigated by a truly independent organisation, not a state employee or agency.”