The Supreme Court on Monday rejected an effort to revive a plea deal for Khalid Sheikh Mohammed, the accused mastermind of the attacks on Sept. 11, 2001.
The agreement would have spared Mohammed the risk of execution in exchange for his guilty plea and a sentence of life in prison without parole.
Mohammed is accused of developing and directing the plot to crash hijacked airliners into the World Trade Center and the Pentagon 25 years ago. Another of the hijacked planes crashed into a field in Pennsylvania.
The plea agreement was approved by military prosecutors and the Pentagon’s senior official for Guantanamo Bay, Cuba, before then-Defense Secretary Lloyd Austin stepped in.
Austin threw out the deal in 2024, saying a decision on the death penalty in an attack as grave as Sept. 11 should only be made by the defense secretary.
Relatives of the Sept. 11 victims were split on the agreements for Mohammed and two co-defendants. Some said a trial is the best path to justice, while others saw it as the best hope for bringing the long, painful case to a conclusion.
Defense attorneys had argued that Austin, who served under President Joe Biden, acted too late. But a divided appeals court panel found Austin acted within his authority.
A trial date has been set for 2028.
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