The Supreme Court on Monday rejected an effort to revive a plea deal for Khalid Sheikh Mohammed, the accused mastermind of the September 11, 2001 attacks. 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.

Background

Khalid Sheikh 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 hijacked plane crashed into a field in Pennsylvania. The plea agreement had been approved by military prosecutors and the Pentagon’s senior official for Guantánamo Bay, Cuba, before Lloyd Austin, then the defense secretary, intervened.