Summary (tl;dr)

The U.S. Supreme Court has declined to revive plea deals for Khalid Sheikh Mohammed and two other alleged 9/11 conspirators, upholding former Defense Secretary Lloyd Austin's decision to revoke agreements that would have spared them the death penalty. This means the defendants will proceed to a military trial where capital punishment remains a possibility.

Essential Background

Khalid Sheikh Mohammed (KSM), identified as the principal architect of the September 11, 2001, attacks, along with co-defendants Mustafa al Hawsawi and Walid bin 'Atash, have been detained at Guantanamo Bay for over two decades. Their military commission prosecutions have been prolonged by legal challenges, including debates over the admissibility of evidence obtained through "enhanced interrogation techniques," or torture. In 2024, plea agreements were reached that would have allowed the defendants to plead guilty to all charges in exchange for life imprisonment, thereby avoiding the death penalty. These agreements were approved by military prosecutors and the Pentagon official overseeing the Guantanamo war court.

The Full Story

In 2024, then-Defense Secretary Lloyd Austin revoked the plea deals just two days after they were accepted, asserting that a decision on the death penalty for an attack of 9/11's gravity should rest with the Defense Secretary. This revocation prompted legal challenges from defense attorneys, who argued that Austin acted too late or lacked the authority to invalidate the agreements. Initially, a military judge and the U.S. Court of Military Commission Review sided with the defense, ruling that Austin lacked the authority to invalidate the deals. However, in July 2025, the U.S. Court of Appeals for the D.C. Circuit overturned these decisions, concluding that Austin "indisputably had legal authority to withdraw from the agreements." On Monday, October 19, 2026, the U.S. Supreme Court declined to hear the appeal from Mohammed and his co-defendants, thereby leaving the D.C. Circuit's ruling intact and solidifying the revocation of the plea deals. A military trial for Mohammed and his co-defendants is now scheduled for June 2028.

Why It Matters

The Supreme Court's decision to deny the appeals means that the long-running legal proceedings for the 9/11 attacks will continue, delaying closure for victims' families who are divided on whether a plea deal or a full trial best serves justice. The ruling reinforces the authority of the Defense Secretary in matters concerning military commissions and the death penalty in high-profile national security cases. It also underscores the persistent complexities and controversies surrounding the military commission system, especially given the history of "enhanced interrogation techniques" used on the defendants.

Geographic Location

• Guantanamo Bay Naval Base, Guantanamo, Cuba (detention and military commission proceedings)
• Washington, D.C., District of Columbia, United States (Defense Secretary's decision, U.S. Court of Appeals for the D.C. Circuit rulings, Supreme Court decision)