The U.S. government has withheld information about a witness who could help clear Canadian Omar Khadr as an "unlawful enemy combatant," Khadr's military defence lawyer at Guantanamo Bay said Thursday.

Omar Khadr is shown in a 2002 file photo, at the age of 15, around the time he was captured by U.S. forces in Afghanistan. The 21-year-old Canadian has been detained at the U.S. military prison in Guantanamo Bay, Cuba, for the past five years.
(Canadian Press)

"It's an eyewitness the government has always known about," Lt.-Cmdr. Bill Kuebler told reporters. "This is something that was buried because nobody ever looked."

Kuebler's comments came after a pre-trial hearing was adjourned at the U.S. naval base in Cuba, where the 21-year-old Khadr has been held for the past five years following his capture by American forces in Afghanistan.

Khadr — who is the only Canadian held at Guantanamo prison and was 15 at the time of his capture in 2002 — is accused of murder in the death of U.S. medic Sgt. First Class Christopher J. Speer in Afghanistan. He is also charged with spying, conspiracy and supporting terrorism.

Kuebler said U.S. officials never bothered to speak to the witness and the prosecution didn't find out about him until recently.

"The significant fact is that the government made us aware of this at the last minute and wanted to go forward with this thing today … notwithstanding being told repeatedly by the military judge that it was not proper," Kuebler told reporters at the base.

"It shows how anxious they are to get this validated and get it moving."

Earlier Thursday, U.S. Col. Peter Brownback, the military judge presiding over the commission, recessed the hearing without ruling whether Khadr would be subject to a military tribunal.

Brownback postponed a decision to name Khadr as an "unlawful enemy combatant" — a designation required in order to move ahead with the military tribunal, according to legislation passed by Congress and signed into law by President George W. Bush in 2006.

In June, the judge dismissed the charges against Khadr because of a technicality, as prosecutors had labelled him as an "enemy combatant," omitting the word "unlawful." Brownback had said the court therefore had no jurisdiction in the case.

In September, a three-panel military appeals court ruled that Brownback's decision was an error and reinstated the terrorism charges.

Khadr co-operative, answers judge's questions

Khadr, whose family lives in the Toronto area, entered the court in the morning dressed in white prison garb. The colour is an indication of a detainee's "highly compliant" status, the CBC's Alison Smith reported from Guantanamo.

The judge scheduled sessions on Dec. 7 and Jan. 11 for lawyers to present motions.

Khadr, whose late father was an associate of al-Qaeda leader Osama bin Laden, is the last prisoner from a Western country at Guantanamo.

During the morning's proceedings, Khadr appeared co-operative with court authorities and told the presiding judge that he accepted Kuebler as his main defence counsel.

Khadr and his legal team were asked if they wanted to enter a plea immediately, but deferred it to a later date.

The trial is taking place without one of Khadr's Canadian lawyers present. Dennis Edney told CBC News on Thursday that the U.S. defence lawyer, Kuebler, barred him from the proceedings because of his criticism of the process, as well as Kuebler's own preparedness and qualifications.

The defence has not interviewed a single prosecution witness, Edney said, while the prosecution has been preparing for the trial for the past two years.

"We have said the military defence lawyers are not ready for trial," Edney said from Edmonton. "We put that in writing to them time and time again.

"My guess? They don't like to be criticized."

The Bush administration created the tribunals following the 2002 invasion of Afghanistan, arguing that neither military courts martial nor U.S. civilian courts were appropriate for trying the Guantanamo detainees because much of the evidence would involve sensitive issues of national security.

In 2006, the U.S. Supreme Court declared the Guantanamo court system illegal, but Washington quickly established a new military tribunal system.

The top court is now hearing a fresh legal challenge to the new tribunal system after a group of prisoners argued they should have the right to go before a U.S. federal court to appeal their indefinite incarceration.

With files from the Canadian Press