By Adam Brookes
BBC News, Guantanamo Bay
The legality of holding terrorist suspects in Guantanamo Bay is once again before the US courts.
Lawyers for an inmate at Guantanamo Bay, Salim Ahmed Hamdan, are arguing that his trial by military commission violates international law.
Guantanamo's inmates are at the heart of a legal wrangle
The case is part of a wrenching battle in the US courts that goes to the heart of the war on terrorism and its legality.
The Bush administration has argued that holding detainees without trial is imperative for national security, but lawyers for the Guantanamo Bay inmates argue that the detentions have no basis in law.
And they label as unconstitutional the procedures put in place in Guantanamo Bay to review the detentions and charge some detainees.
Some 540 detainees remain at Guantanamo Bay.
There they go through three procedures which the Bush administration and the US military argue provide them with sufficient protection of their rights.
A Combatant Status Review Tribunal decides if the detainee is an 'enemy combatant'.
The detainee wore an orange jumpsuit, signalling that he was a 'non-compliant' prisoner
An Administrative Review Board, or ARB, decides if a detainee should be released because they pose no threat to the US, or whether they should be detained for another year.
And a military commission will try those who are deemed to have committed crimes.
The BBC observed an ARB - the first time journalists had been allowed to do so. We saw only the unclassified part of the proceedings.
Our military escorts took us into Camp Delta - where the detainees are held - to a prefabricated building.
Before the proceedings began, they briefed us on what we would see. One officer likened the proceedings to a parole hearing - even though the detainees have not been found guilty of any crime.
He stressed that this was not a legal hearing, and standards of proof and evidence normal for a civilian court would not apply.
Salim Ahmed Hamdan is challenging the tribunals' legality
The detainee whose review we would witness was a young man from Saudi Arabia, we were told.
Under no circumstances were we to publish his name, said our escorts, and we had to sign a piece of paper to that effect.
But the detainee was suffering from a stomach upset. We watched, on camera, as he was examined in an adjoining room.
A doctor questioned him gently through an interpreter, and decreed he was too ill to go ahead with the review board. The proceedings were postponed.
The following day we returned. The detainee was apparently feeling better and the proceedings went ahead.
Three military officers sat on the board. None of them were lawyers.
Their job, as they described it, was to review the evidence and come to a recommendation as to whether the detainee constituted a continued threat to the US and should be further detained, or whether he should be transferred to his home country, or released.
Military hearings do not work to the same standards as courtrooms
The detainee was already sat when we entered the room. He wore an orange jumpsuit, signalling that he was a "non-compliant" prisoner.
His hands and feet were shackled to the floor. At a guess he was in his late 20s, a rangy young man with a thin beard and a shock of curly hair.
He looked rigidly at the floor, apparently to avoid any eye contact.
At the detainee's side was an "Assisting Military Officer". His role was to assist the detainee in presenting his case, but he appeared well short of legal representation.
Also present was a "Designated Military Officer", whose role was to present the evidence. He did not resemble a prosecutor. There was no adversarial argument.
After the board had been sworn in, they listened to a litany of allegations against the detainee.
'Rifles and trenches'
We were not permitted to record the proceedings, so the following is reconstructed from my notes.
We heard that he had travelled to Pakistan and Afghanistan. He had allegedly received weapons training in a camp in Afghanistan run by Lashkar e-Tayyiba, a group listed by the state department as a terrorist organisation.
In 2001, we heard, the detainee had fought on the front line in Afghanistan, alongside the Taleban during the retreat from Bagram, and there he had fired his Kalashnikov rifle. He then fled to a location near Jalalabad, where he "dug trenches and waited".
Images of bound and shackled prisoners shocked the world
His name was found, the board heard, on the hard drives of computers seized during raids on al-Qaeda safe houses in Pakistan.
The sources of these allegations were never revealed. It was unclear to us if they came from his own testimony, or intelligence, or elsewhere.
No witnesses were called, and the detainee sat silent throughout the hearing.
During the interrogations that followed his capture, we heard, he had stated that he would follow any religious decree; that an attack on the US was necessary; that infidels should either convert to Islam, or pay a fee, or be killed.
He had also threatened to kill prison guards and their families.
The board then heard a list of "mitigating factors". The detainee had told his captors that he had gone to Afghanistan for sightseeing. He had gone to Pakistan to buy hashish. On hearing this, in his only visible show of emotion, a broad smile spread across the detainee's face.
He had said he had never picked up a weapon. And he had no knowledge of terrorist attacks against the US, nor did he have anything against the US.
Much of what came under "mitigating factors" stood in direct contradiction to what had gone before.
It was unclear to us what criteria the board intended to use to weigh these contradictory accounts of the young man's past.
Finally it was time for the detainee to speak (translated through an interpreter, a young Arab-American woman who appeared extremely competent).
"I don't have hostility to any person and I want the whole world to live in peace," he said.
He said he had gone to Pakistan "for a change of weather", and to get to know the country.
He was quietly spoken, calm, and brief.
The Assisting Military Officer weighed in. He went through the evidence against the detainee point by point and detailed which elements the detainee rejected as false.
True or false?
Next came questioning by three officers on the board. A good 10 minutes was taken up with the board trying to establish the correct spelling of the detainee's name.
The chairman asked what the detainee would do if he were released.
Detainee: "I would go back to my country. I don't know what I would do. I would live with my family."
Question: "Who did you fire your rifle at?"
Detainee: "I never fired a rifle."
Question: "Why were you firing?"
Detainee: "I never fired."
Question: "Why were you in Afghanistan?"
Detainee: "For a visit."
Question: "How do you explain the differences in the evidence?"
Detainee: "I can't."
Question: "How would you describe your behaviour with the guards here [at Guantanamo Bay]?
Answer: "If the guards treat me well and respect me, I will treat them well and respect them. If they are different from that, I will give them my back and not talk to them, because it will cause me problems and I don't want problems.
"The soldiers [the camp guards] lie about us a lot. They say an incident happened and it did not. They say we spit at them when we did not. They lie a lot."
There were questions regarding the detainee's health, and with that, it was over. The officers went into a classified session during which they would hear secret evidence.
And the detainee would never know what secret evidence against him existed.
We were struck by the cursory nature of the questioning, and the absence of an attempt to reconcile conflicting claims as to what the young, sullen detainee had actually done.
More than 60 of these boards have now taken place.
And on the basis of their recommendations, senior Pentagon officials decide if detainees remain in captivity or go free.
But the legal challenges to the procedures in place in Guantanamo Bay are mounting, and some judges are proving sympathetic to those challenges.