The Supreme Court has ordered a new trial for Richard Glossip after Oklahoma Attorney General Gentner Drummond said an appeals court made a "remarkable and remarkably flawed decision" to uphold his death row conviction and sentence.

The new trial means his previous conviction has been thrown out, and whether prosecutors will try Glossip again remains unclear.

The Supreme Court voted 6-2 in favor of a new trial, with Justices Clarence Thomas and Samuel Alito voting against it. Justice Neil Gorsuch did not vote.

Glossip was convicted for the 1997 murder of Barry Van Treese. Glossip's conviction depended on the testimony of Justin Sneed, who admitted to fatally beating Van Treese with a baseball bat.

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Sneed was spared the death penalty in exchange for his testimony against Glossip. But Drummond noted that Sneed gave inconsistent testimony when Glossip was tried.

One key piece of evidence allegedly withheld by prosecutors in 2004 was that it was known that Sneed had been diagnosed with bipolar disorder and prescribed lithium. Sneed testified that he did not receive medical treatment for mental issues, a claim prosecutors at the time knew was false. That information might have been helpful to Glossip's defense, Drummond argued.

Drummond has contended that prosecutors committed a Brady violation by not sharing potentially exculpatory evidence with Glossip's defense team.

“Dismissing violations of those constitutional bedrocks on the ground that suitably skeptical and intrepid defense counsel should have assumed the government was concealing and prevaricating and gotten to the truth anyways eviscerates those bedrock precedents,” Drummond said in his filing to the Supreme Court. “And the notion that a reasonable factfinder would have ignored evidence that the prosecution’s star witness was suffering from a serious mental illness and committed perjury is equally unfathomable.”