The military trial of alleged 11 September mastermind Khalid Sheikh Mohammed and three other defendants is scheduled to begin at Guantánamo in 2028, nearly 27 years after the attacks that killed around 3,000 people. The date marks another attempt to bring one of the longest-running and most contentious US terrorism cases before a court.
The trial is scheduled to open on 5 June 2028 at the US detention facility in Guantánamo, Cuba, according to an order issued by the military judge overseeing the case. The date is not yet guaranteed, however, as several procedural decisions must be resolved before proceedings can formally begin. The case has been delayed for years, reflecting the complex legal issues surrounding the prosecution of Mohammed and the other defendants.
Mohammed has been held at Guantánamo for years and is regarded as the principal planner of the 11 September attacks. He is alleged to have organised both the financing and communications for the operation on behalf of Al-Qaeda. On 11 September 2001, Islamist terrorists hijacked four passenger aircraft in the United States. Three were flown into the World Trade Centre in New York and the Pentagon near Washington, while the fourth crashed in Pennsylvania. Around 3,000 people were killed in what remains the deadliest terrorist attack in US history.
Mohammed was arrested in Pakistan in 2003 and subsequently interrogated by the US Central Intelligence Agency. According to a report by the US Senate, he was tortured during those interrogations. He was transferred to the US detention facility at Guantánamo in 2006, where he was due to face trial before a military tribunal over his alleged role in the 11 September attacks. The proceedings against Mohammed and several co-defendants were repeatedly delayed, leaving the case unresolved for decades.
A major development came last year when an agreement was offered that would have allowed Mohammed and two co-defendants to plead guilty in return for avoiding the death penalty. The agreement was accepted by the official responsible for the Pentagon’s Guantánamo military commissions, but was later revoked in August by then-Defence Secretary Lloyd Austin following criticism of the deal from Republican members of Congress.
Last month, a US appeals court rejected an attempt by Mohammed and two of his co-defendants to enter guilty pleas under such agreements. The ruling overturned decisions by a military judge and the US court responsible for reviewing military commissions, both of which had supported the proposed plea arrangement. The dispute over the agreements has added another layer of legal uncertainty to a case already marked by years of procedural battles.
Guantánamo itself remains closely associated with the post-9/11 US detention system. The facility was established under Republican President George W. Bush after the attacks to hold suspected Islamist terrorists without trial. At its peak, almost 800 people were detained there. Human rights organisations have long called for the camp to be closed, but a small number of detainees remain there.
The planned 2028 trial would therefore come almost 27 years after the attacks themselves, with the proceedings still dependent on unresolved legal and procedural decisions. For the defendants, the victims’ families and the US justice system, the case remains one of the most consequential unresolved chapters of the 11 September attacks.
