Oklahoma execution team failed to place IV in Clayton Lockett's vein, according independent autopsy

Preliminary results from an autopsy conducted on the Oklahoma inmate involved in last April's botched execution bolster claims that prison officials failed to properly administer the lethal dose of drugs used in the procedure.

The autopsy, carried out by an independent medical examiner, suggests the execution team failed on multiple occasions to insert an IV into 43-year-old Clayton Lockett's arms. This despite the fact that the veins were in "excellent integrity… for the purpose of achieving venous access."

The report says officials instead chose an entry point near the groin, which was considered riskier and more painful.

Lockett, who was convicted of murder and rape, eventually died nearly 30 minutes after the procedure began. Witnesses said he writhed in pain and struggled against his restraints shortly after the first drug was administered.

Lockett's lawyers say these findings disprove the state's position that one of his veins "blew out" after the drugs were administered. Oklahoma officials did not comment on the latest results, but said they will release the findings of their own autopsy in the coming weeks.

Meanwhile, the state has come under