The governor of Oklahoma is rejecting calls to delay the execution of a man who anti-death penalty advocates -- including Sister Helen Prejean and actress Susan Sarandon -- say is innocent.

Oklahoma inmate Richard Glossip, 52, is scheduled to be executed by lethal injection on Sept. 16 for the 1997 murder of his boss, motel owner Barry Van Treese.

Glossip -- a former hotel manager -- did not kill Van Treese. His coworker, Justin Sneed, a motel handyman, confessed to bludgeoning the father of seven to death with a baseball bat, but later claimed it was Glossip's idea.

"Once a mistake is made in a judicial system, people just do not want to admit that a mistake has been made, so it becomes impossible case, after case, after case to readdress them."

- Actress Susan Sarandon

In a video with police, detectives are heard telling Sneed they believe he was not solely responsible for the murder -- a tape never seen by the courts. Sneed then named Glossip as a conspirator, later testifying Glossip offered him $10,000 to kill Van Treese after his boss accused Glossip of embezzlement and mismanagement.

In exchange for his testimony against Glossip, Sneed received a plea deal of life without parole while Glossip was sentenced to death in 1998.

"The governor of Oklahoma is just a horrible person -- and a woman, so it's even more discouraging," Sarandon said in an exclusive interview with Sky News.

 

In January 1997, Glossip worked as the manager of the Best Budget Inn in Oklahoma City -- owned by Van Treese. Glossip also lived there with his girlfriend D-Anna Wood and had hired Sneed for maintenance work at the motel.

On January 6 of that year, Van Treese and his wife reviewed the books and reportedly discovered more than $6,000 in shortages from 1996. The next day, Van Treese was found beaten to death in Room 102 at the inn.

The victim's wife later testified that her husband intended to confront Glossip about the shortages. Prosecutors argued that Glossip, who had no prior criminal record, paid Sneed to murder Van Treese because he feared the two would be fired. Glossip has always maintained his innocence.

Glossip was first convicted of first degree murder and sentenced to death in 1998. The Oklahoma Court of Criminal Appeals later overturned his conviction, citing ineffective legal counsel. In a 2004 retrial, Glossip was again convicted of first degree murder and sentenced to death. He appealed that conviction, and his appeal was denied by the Oklahoma Court of Criminal Appeals, the United States District Court for the Western District of Oklahoma, the United States Court of Appeals for the 10th Circuit Court, and then the Supreme Court of the United States.

Anti-death penalty advocates say shoddy legal representation as well as lack of solid evidence should grant a stay for Glossip. Sarandon is calling on Oklahoma Gov. Mary Fallin to delay the execution so that his attorneys can present new evidence in the case.

"He's clearly innocent," Sarandon told Sky News. "Once a mistake is made in a judicial system, people just do not want to admit that a mistake has been made, so it becomes impossible case, after case, after case to readdress them."

"Both trials -- nobody saw the video of the confession where police are practically spoon feeding him [Sneed] what he should say?" said Sarandon, one of whose greatest roles was that of Sister Helen Prejean in the death row drama "Dead Man Walking."

Prejean, who is famous for her work with death row inmates, penned a detailed account of the case based on her time spent with Glossip. In it, she states there was, "no physical evidence to corroborate Sneed’s testimony against Richard."

But Fallin, a Republican, is not backing away from her position. Alex Weintz, Fallin's spokesman, told FoxNews.com the governor does not have the ability to grant clemency to Glossip. The limit of her legal ability to intervene is to grant a 60-day stay, which she is not willing to do, he said.

"Richard Glossip has been convicted of murder and sentenced to death by two juries," Fallin said in a statement Monday. "His conviction and death sentence have been reviewed and upheld by four courts, including the Supreme Court of the United States ... His actions directly led to the brutal murder of a husband and a father of seven children. The state of Oklahoma is prepared to hold him accountable for his crimes and move forward with his scheduled execution."

"Richard Glossip was first convicted of murder and sentenced to death over 17 years ago," she said. "He has had over 6,000 days to present new evidence. Postponing his execution an additional sixty days does nothing but delay justice for the family of Mr. Van Treese."

FoxNews.com's Cristina Corbin contributed to this report.