Christa Pike is now speaking in full sentences and walking with far less help just three weeks after surviving her infamous failed execution attempt.

The 50-year-old was given two doses of pentobarbital as the state of Tennessee tried to carry out her death sentence on September 30. She somehow survived and was taken to hospital, where she remained unconscious and needed a ventilator.

One of her lawyers told TMZ on Wednesday that her speech has improved considerably in recent days. Her mobility has also improved, allowing her to walk more independently as she continues her recovery in prison.

But medical staff are still monitoring her cognitive and psychological functioning. Her lawyer said it could take another month or longer to establish whether she has suffered any lasting damage or not.

Pike had been due to become the first woman executed in Tennessee in more than 200 years. She was sentenced to death in 1996 for torturing and murdering her 19-year-old classmate, Colleen Slemmer, the previous year.

Both were students at the Job Corps Centre in Knoxville. Pike was 18 when Slemmer was killed on January 12, 1995.

Prosecutors said Pike believed Slemmer was interested in her boyfriend, Tadaryl Shipp. Slemmer was attacked near the University of Tennessee’s agricultural campus, where she was beaten and stabbed before Pike struck her head with a large piece of asphalt.

More than three decades later, Pike was taken to the execution chamber at Riverbend Maximum Security Institution in Nashville. Her lawyers say that the team carrying out the lethal injection repeatedly struggled to establish access to a vein.

According to a court filing from her legal team, at least seven needles were used during the attempt. One was bent at a 90-degree angle when it was removed, the filing said.

Her lawyers said she could be heard crying, whimpering and breathing loudly during the procedure. They reported that both her arms were swollen, burned and blistered when she arrived at hospital.

Pike’s legal team said they were subsequently told that she was totally brain dead and would soon be taken off life support. On October 6, however, she regained consciousness and began speaking.

Her lawyer Randy Spivey said that ‘to the shock of everyone, including me, including her team and including the medical team, Christa woke up and began talking’.

According to Spivey, her first words were: ‘Where am I and who are you?’

He said she also asked about Slemmer’s family.

Pike’s lawyers reported that she suffered pneumonia, a blood clot in her arm and difficulty eating following the execution attempt.

Spivey described ‘extraordinary’ swelling in her hands, saying they ‘looked like if you were to blow up a surgical glove’.

She was discharged from hospital on October 10 and transferred back to prison to continue receiving the necessary medical care.

Tennessee governor Bill Lee halted the state’s remaining executions for the year following the high profile botching of Pike’s execution.

Former US attorney Ed Stanton has been appointed to carry out an independent review into what happened.

The state’s prison chief, Frank Strada, also resigned in the aftermath. He said that stepping down while the review was conducted was ‘in the best interest of Tennesseans’.

Pike’s lawyers have urged Lee to commute her sentence to life imprisonment without the possibility of parole, preventing another attempt to execute her. They argue she has ‘endured punishment greater than any other person in the history of the American death penalty’.

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