The former driver for Osama bin Laden will be the first Guantanamo detainee to go on trial Monday under President George W Bush's controversial military commissions, dpa reported.
Yemeni Salim Hamdan faces charges of conspiracy and providing material support for terrorism in what will be the first test for the tribunals. He faces a maximum sentence of life in prison.
The Pentagon has charged 20 detainees, and dozens more could be brought before a military judge on the remote naval station on Cuba.
Hamdan's lawyers sought to delay the trial so he could challenge the constitutionality of the legal proceedings, but a federal judge on Thursday in Washington dismissed the petition.
Defence lawyers argue that Hamdan was merely a driver for bin Laden and was not a member of al-Qaeda, and point out that he played no role in any terrorist attacks.
Hamdan has been among the most active Guantanamo detainees challenging the legal process in federal court, including in a key ruling by the US Supreme Court in June 2006 that Bush's commissions were unconstitutional and violated the Geneva Conventions.
The decision forced the White House to revamp the process and get congressional approval, which took place several months later. The Pentagon had to refile all of the charges against Hamdan and the other detainees.
Australian David Hicks is the only suspect convicted under the tribunals. He pleaded guilty, was allowed to serve nine months in jail in his home country and has since been freed.
Hamdan alleges that he was abused while in US custody and during intense interrogations. US officials believed that as bin Laden's driver and body guard, he would know the location of the al-Qaeda figurehead.
The US military believes that Hamdan aided al-Qaeda and the Taliban on the battlefield in Afghanistan by transporting weapons, and that he helped bin Laden escape a cordon of US forces in December 2001 during the battle in Tora Bora.
Hamdan was captured by Afghan forces in 2001 and transferred to US custody. He was shipped off to Guantanamo the following year and has been held in solitary confinement.
Hamdan is not the biggest suspect facing charges. The trial of the mastermind of the September 11, 2001, terrorist attacks, Khalid Sheikh Mohammed, and four other defendants in the death penalty cases could get underway as early as September. Mohammed declared during a hearing in June that he wanted to by martyred.
Human-rights groups have said that the tribunals do not provide the detainees with the rights afforded by US civilian courts and are designed to produce convictions.
"These are second-class trials to which the US government would not subject its own nationals," Amnesty International said Friday.
The military rejects the argument, saying that defendants have military-appointed attorneys but are permitted to seek private counsel as well. They will be allowed to summon witnesses to testify on their behalf and to question witnesses testifying against them. They will also be permitted to review the evidence presented against them.