Supreme Court Rejects 9/11 Mastermind's Bid to Revive Plea Deal

The US Supreme Court on Monday, October 19, 2026, declined to hear a bid by Khalid Sheikh Mohammed, the accused mastermind of the September 11, 2001, attacks, to revive a 2024 plea agreement.

The agreement would have spared him the death penalty in exchange for a guilty plea. The justices turned away appeals by Mohammed and two co-defendants, Mustafa al Hawsawi and Walid bin 'Atash, who had also signed plea agreements. The Supreme Court's unsigned opinion did not explain why the appeal was rejected. Justice Brett Kavanaugh recused himself from the decision.

Former Defense Secretary Lloyd Austin scrapped the plea deals two days after they were offered and accepted by the US official overseeing the Pentagon's Guantanamo war court in 2024. The deals were made during the administration of President Joe Biden. Republican lawmakers criticized the agreements. An appellate court ruled last year that Austin had acted within the bounds of his legal authority, rejecting an argument that he had acted too late.

A military judge had previously ruled that Austin lacked authority to invalidate the plea deals, a decision upheld in December by the US Court of Military Commission Review. The Supreme Court's action marks the latest milestone in a military prosecution of detainees held in Guantanamo Bay, Cuba, that has been beset by two decades of legal gridlock.

Mohammed remains the most well-known inmate at the Guantanamo detention facility, which was set up in 2002 by then-US President George W. Bush to house foreign terrorism suspects. In August, a US Air Force judge set the trial for Mohammed and his co-defendants for June 2028. Much of the legal jousting in the cases has focused on whether the defendants could be tried fairly after having undergone torture at the hands of the CIA.