Lawyer for 9/11 supremo: this is not a fair trial

Despite promises to close the Guantanamo detention facility, 167 inmates remain (Getty Images)

A US Army officer representing one of Guantanamo Bay's most notorious prisoners has spoken out against the secretive nature of the Military Commissions system, insisting it risks becoming little more than a "show game" to execute suspects, denying them and the American people the right to a fair trial.

Captain Jason Wright was appointed by the military to represent Khalid Sheikh Mohammed, who is charged along with four others with conspiring and executing the 9/11 attacks. Yet, the officer revealed to i, rafts of vital evidence – including the three and half years his client spent at secret CIA "black" sites – have been deemed classified.

It was only through a Freedom of Information request that redacted files were released showing that Mohammed had been subjected to waterboarding 183 times, kept awake for seven days straight and had his family's lives threatened.

While the accused face the death penalty if convicted, they are likely to be detained indefinitely even if they are acquitted, a situation Capt Wright likened to torture.

"This is not a trial. It is an attempt to legitimise a death threat," he said. "It can never be fair to bring a man to the brink of death and back 183 times with waterboarding and then do it a final 184th time – but this time it will have full state sanction. The bottom line is, torture denies justice. If you believe fundamentally that America is better than that, then this is a struggle for the soul of America."