Washington — The Supreme Court on Monday said it would take up the case of Oklahoma death row inmate Richard Glossip after the state's attorney general argued his conviction and sentence should not stand due to issues with his trial.

Glossip, 60, has avoided execution three times, and in April, Oklahoma Attorney General Gentner Drummond told the state's Pardon and Parole Board that he supports granting clemency for the death row inmate due to concerns about the fairness of Glossip's trial. He cited two independent reviews of the case that suggested Glossip receive a new trial. The state parole board, though, voted not to recommend clemency for Glossip.

Drummond also asked the Oklahoma Court of Criminal Appeals last year to toss out Glossip's conviction and raised concerns about the testimony of a key witness and evidence, though the court rejected the attorney general's request in March, which cleared the way for Glossip's execution in May.

Days before he was scheduled to be put to death, the Supreme Court intervened and blocked the state from executing Glossip while it considered whether to take up his case. The high court will now decide whether due process of law requires reversal of Glossip's conviction given that it is "so infected with errors that the state no longer seeks to defend it," as described in his request for the Supreme Court to review his case. Justice Neil Gorsuch recused himself from the case. Though a brief order from the court did not include a reason for Gorsuch's recusal, it likely relates to his time as a judge on the U.S. Court of Appeals for the 10th Circuit, which covers Oklahoma.

"Mr. Glossip is innocent of the murder for which he faces execution. He has no criminal history, no history of misconduct during his entire time in prison, and has maintained his innocence throughout a quarter century wrongfully on death row," John Mills, Glossip's attorney, said in a statement. "It is time — past time — for his nightmare to be over. The court should reverse the Oklahoma Court of Criminal Appeals, which has inexplicably refused to accept the state's confession of error."

Drummond pledged to continuing pursuing justice in Glossip's case, saying in a statement that "public confidence in the death penalty requires the highest standard of reliability, so it is appropriate that the U.S. Supreme Court will review this case."

Glossip was convicted in the killing of his former boss, motel owner Barry Van Treesee, in 1997. His conviction at two separate trials — the first was reversed due to ineffective assistance of counsel — largely hinged on the testimony of his co-defendant, Justin Sneed, who admitted to robbing and killing Van Treese after Glossip agreed to pay him $10,000, he said. Sneed was sentenced to life in prison. Glossip has long said he is innocent.

The case has attracted widespread attention, including from actress Susan Sarandon and reality TV star Kim Kardashian, who pushed her social media followers last year to contact the pardon board to request a grant of clemency or Oklahoma Gov. Kevin Stitt to pardon Glossip.

In their request that the Supreme Court take up Glossip's case, his lawyers told the justices that his conviction "is a grave miscarriage of justice and to execute him would be an unthinkable, irreversible travesty."

"The court, like the OCCA, faces a stark choice: whether the state of Oklahoma can execute a person who its chief law enforcement officer believes is wrongly convicted because of state misconduct," Glossip's lawyers wrote in a filing, referring to the Oklahoma Court of Criminal Appeals. "The Oklahoma Attorney General made a careful, deliberate choice to concede error in this case."

Supporting Glossip in his request for the Supreme Court to take up his case was Drummond, who told the justices in May that after a review of new information, Glossip's "conviction and capital sentence cannot stand." The attorney general argued that the refusal by the Oklahoma Court of Criminal Appeals to vacate his conviction "cannot be the final word in this case."

"The prospect of executing an individual based on a conviction that the state's chief law enforcement officer believes, after careful scrutiny, was secured by prosecutorial misconduct in violation of due process, is all but unthinkable," he wrote in a filing to the court. 

Drummond added that the lower court's denial of a new trial for Glossip is "wrong on the facts and wrong on the law. It cries out for correction."

Key among the issues with Glossip's prosecution that were identified in an investigation of the case conducted by an independent counsel was Sneed's credibility as a witness. Evidence previously withheld by the state and made available to the defense in January showed that Sneed was evaluated by a jail psychiatrist and diagnosed with bipolar affective disorder in 1997, after the murder and while he was in jail. Sneed was prescribed lithium by the psychiatrist, and interview notes from 2003, which Drummond said were not turned over by the state, indicated the prosecutor knew about Sneed's treatment.

"Despite this reality, prosecutors allowed Sneed to effectively hide his serious psychiatric condition and the reason for his prior use of lithium through false testimony to the jury," Drummond wrote, citing Sneed's testimony at the second trial in 2004, during which he claimed he never saw a psychiatrist.

He added that had the jury known that Sneed, an "indispensable" witness for the state, was treated by a psychiatrist and administered lithium for a "serious psychiatric condition," it would have had a "material impact" on their view of his credibility, especially when combined with his "known and extensive illicit drug use."

"The state is fully aware of the stakes of this case, for Glossip, the victim's family, and the rule of law. Indeed, the state deeply respects the victim's family's concerns about ensuring justice be done, both here specifically and in capital litigation generally," Drummond wrote. "But justice would not be served by moving forward with a capital sentence that the state can no longer defend because of prosecutorial misconduct and cumulative error."

Melissa Quinn

Melissa Quinn is a politics reporter for CBSNews.com. She has written for outlets including the Washington Examiner, Daily Signal and Alexandria Times. Melissa covers U.S. politics, with a focus on the Supreme Court and federal courts.

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