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.