Five Guantánamo prisoners accused of plotting the September 11 attacks were back before a military tribunal on Monday for pre-trial hearings after months of delay.

Khalid Sheikh Mohammed – the alleged mastermind of 9/11, the worst terrorist attack in US history – and his four co-defendants sat quietly at the defence tables, watched by military guards. Defendant Mustafa Ahmad al-Hawsawi responded to the judge's questions about his request for additional legal counsel, according to the Associated Press, before the hearing was adjourned.

The calm start to the proceedings was in sharp contrast to the previous hearing in May, which was marred by protests, outbursts and the defendants' refusal to answer questions from the judge. It lasted 13 hours.

The hearings, in Camp Justice, the war court compound at the US naval base in Cuba, are expected to focus on secrecy and transparency, but will cover a range of issues from whether the prison camps can force the men to attend their own trials to what they can wear in court, the Miami Herald reported.

The hearings are part of the legal proceedings required to move the case to trial, estimated to be at least a year away. They were scheduled for August but delayed by tropical storm Isaac.

Mohammed, a Pakistani citizen from Kuwait, who attended college in North Carolina, has told military officials that he planned the 9/11 attacks "from A to Z" and was involved in about 30 other terrorist plots. He has said, among other things, that he personally beheaded Wall Street Journal reporter Daniel Pearl. The other defendants in addition to Ahmad al-Hawsawi are Ramzi Binalshibh; Walid bin Attash; and Ali Abd al-Aziz Ali.

All five could face the death penalty if convicted.

The five men were in the custody of the CIA for four years before being brought to the base for detention and trial. One of the key issues at this week's hearing will be how much the men's lawyers and the wider world will be allowed to learn about what happened during that time.

The government argues that whatever the men say about their time in the CIA's secret network of "black sites" is classified at the highest levels.

Prosecutors have asked the judge to approve what is known as a protective order that is intended to prevent the release of classified information during the eventual trial of the five.

Lawyers for the defendants say the proposed rules will adversely affect their defence. The American Civil Liberties Union, which has filed a challenge to the a protective order, says the restrictions will prevent the public from learning what happened to Mohammed and his co-defendants during several years of CIA confinement and interrogation.

The order requires the court to employ a 40-second delay during legal proceedings, so that reporters, who watch behind soundproof glass, can be stopped from hearing details of the CIA's classified rendition and detention programme from officials, lawyers or the defendants themselves.

Hina Shamsi, an ACLU attorney who will be arguing against the protective order during the pre-trial hearing, said: "What we are challenging is the censorship of the defendants' testimony based on their personal knowledge of the government's torture and detention of them."

The order, which is also being challenged by a coalition of media organizations, is overly broad because it would "classify the defendants own knowledge, thoughts and experience," she said.

"It's a truly extraordinary and chilling proposal that the government is asking the court to accept," Shamsi said.

In court papers, military prosecutors argue that the trial requires additional security because the accused have personal knowledge of classified information such as interrogation techniques and knowledge about which other countries provided assistance in their capture.

"Each of the accused is in the unique position of having had access to classified intelligence sources and methods," the prosecution says in court papers. "The government, like the defense, must protect that classified information from disclosure."

Brigadier general Mark Martins, the chief prosecutor for the military commissions, said on Sunday that the security precautions are necessary to prevent the release information that could harm US intelligence operations or personnel around the world, and not to prevent embarrassing the government or to cover up wrongdoing.

"Our government's sources and methods are not an open book," Martins told the Associated Press.

Some details of the five defendants' treatment are public knowledge. The CIA's declassified documents record Mohammed being waterboarded 186 times.

In May, David Nevin, Mohammed's defence attorney, told reporters after the 13-hour hearing: "The government wants to kill Mr Mohammed. They want to extinguish the last eyewitness to his torture so that he can never speak about it."

The May hearings followed a failed attempt to try the five men in Guantánamo in 2008.

Families of 9/11 victims have been invited to watch the pre-trial hearings in military facilities in New York, New Jersey, Massachusetts and Maryland. Seven family members were viewing the Guantánamo proceedings on Monday via closed-circuit television at Fort Hamilton, a base in Brooklyn.

In addition to 9/11 families and first responders, the general public can watch the proceedings at Fort Meade, in Maryland.

© 2012 Guardian News

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