Six-and-a-half years after the September 11 terror attacks, the accused mastermind and four other co-conspirators are facing a war-crimes tribunal at the U.S. detention center at Guantanamo Bay, Cuba. The arraignment of Khalid Sheikh Mohammed and the four others is the highest-profile test yet of the controversial tribunal system, which is under review by the U.S. Supreme Court. All five men face the death penalty if convicted. VOA's Al Pessin has this report from the Guantanamo Bay detention center.

Sun sets over Camp Justice and its adjacent tent city, legal complex of US Military Commissions, at Guantanamo Bay US Naval Base, 04 Jun 2008

The defendants will face a military judge for the first time Thursday to hear the charges against them formally read. They will have the opportunity to enter a plea and may also be allowed to speak to the court about other issues, such as the conditions of their detention and interrogation. Charges against a sixth detainee were withdrawn last month without explanation, but experts note he has claimed some of the evidence against him was obtained through torture.

This will be the first public appearance for the five men, who have been held by the U.S. government for years, first in secret CIA prisons and now at Guantanamo. Reporters, lawyers and human rights activists will be allowed to watch the hearing, but no sound, video or pictures will be made public. In addition, sound from the hearing will be delayed several seconds to enable military officials to turn it off if someone reveals secret information.

The process for trying the men before what are called Military Commissions was created specifically for detainees in the war on terrorism. But the original system was struck down by the U.S. Supreme Court, and the court is now considering a case which could invalidate the revised process. Still, the senior military officer responsible for the process, Brigadier General Thomas Hartmann says the defense department is adding dozens of staff members to his team in an effort to move forward with arraignments and trials as quickly as possible.

Brig. Gen. Thomas Hartmann briefs members of media at Guantanamo Bay US Naval Base, 04 Jun 2008

Speaking to reporters here Wednesday evening, General Hartmann addressed one of the main controversies surrounding the process, the use of secret evidence.

"Every piece of evidence, classified or not that goes to the finder of fact will be subject to review, cross examination, challenge and understanding by the accused and his counsel," he said.

The 'finder of fact' will be a military jury. General Hartman's statement raises the possibility that secret evidence could be revealed to al-Qaida members but not to the public, but that would likely only happen much later in the process. In these commission trials, the defendants are prosecuted, judged and represented by U.S. military lawyers, but private lawyers have volunteered to be part of the defense team.

Activists like Joanne Mariner of Human Rights Watch are not convinced that this process will be fair, as General Hartmann says it will. They say the military process does not sufficiently protect the defendants' rights, particularly regarding evidence obtained through mistreatment. General Hartmann says that decision will be made by the military judge in each instance.

Mariner, who will be an observer at Thursday's hearing, says the relatives of the nearly three thousand victims of the attacks, and the public at large, deserve a more reliable process, like the regular U.S. federal courts.

"A case as important as the September 11th terrorist attacks on the United States should be tried fairly in federal court so that the result is some kind of finality in which both the U.S. public and the world can recognize that the result of the trial is reliable and credible," said Mariner.

The Bush administration is opposed to using federal courts to try the terrorism suspects, in part because of the secret evidence.

The best-known of the men going on trial Thursday is Khalid Sheikh Mohammed, known as the mastermind of the September 11th attacks. His alleged co-conspirators are Ramzi Binalshibh, Walid Muhammed 'Attash, Ali Abdul Aziz Ali and Mustafa al Hawsawi. Charges against Mohammed al Kahtani were dropped, but officials say they may be reinstated later. He is believed to have planned to be one of the September 11 hijackers.

The arraignment will take place in a specially built building on this U.S. Naval Base, not far from the detention center where 275 detainees are held. Several others have also been charged and their trials are proceeding. Officials expect to charge and try more of the detainees, but some have been approved for release and others may remain in custody without being charged.

These five detainees could face the death penalty if they are convicted, but if any of them is acquitted he could still be kept in custody as an enemy combatant.

Both President Bush and Defense Secretary Robert Gates have said they would like to close the Guantanamo detention center, but Secretary Gates acknowledged recently that he has not made much progress toward finding an alternative way to deal with the terrorism suspects held here.