The Australian Defence Force's top lawyer has added his voice to the chorus of concern about the US military commission set up to try terror suspect David Hicks.
But the federal government is standing firm amid mounting criticism over the integrity of Hicks' upcoming trial and says it will not protest against the military commission process.
Captain Paul Willee, a prominent Queen's Counsel, said the Hicks commission would be a charade if claims that the process was rigged to produce guilty verdicts were true.
The process would breach natural justice if that was the case, Capt Willee said, speaking as a private citizen and not in his role with the defence force.
In emails to their superiors, two former US prosecutors who had been involved with the military commissions described the process as flawed and rigged to produce guilty verdicts against mainly low level suspects.
The Pentagon says it has investigated claims made in the emails and found them to be "much ado about nothing".
Capt Willee said the Pentagon's assurances must be authenticated.
"If what's been said in the email that we have seen is true, then I would describe it as a charade," Capt Willie told ABC radio.
"It breaches every single precept of natural law and justice in the criminal context.
"There are those who in our community take the view that when the allegation is made by somebody in the lion's den, you don't get the head lion to deal with it."
Capt Willee said he had serious ethical concerns about the military commission process, which was akin to the system Australia abandoned after World War II.
"It denies people access to evidence, to the ability to cross-examine those who made the statements that might be used against them and generally flies in the face of all the rules of fairness that we have developed over the last 50 to 60 years," he said.
"I would like to see at very least the Hicks matter transferred to a civilian or a military court martial set up in accordance with the rules the Americans use to try their own alleged miscreants, rather than some specialised process which cuts across those military safeguards, or appears to do so."
Prime Minister John Howard acknowledged criticism surrounding the commission process but said he had no option but to allow the trial to go ahead because Hicks could not be tried in his home country.
"We have (had) legal advice from the Crown law authorities, time and time again, which effectively says that there was no criminal offence covering Mr Hicks behaviour at the time and if he comes back to Australia he will effectively escape any kind of trial," Mr Howard told reporters.
Mr Howard said he was satisfied the claims by the former US prosecutors had been investigated.
But Hicks' US military lawyer Major Michael Mori said that was not good enough.
"It is no longer appropriate for the Australian government to rely on US assurances as to the legality of the military commissions," Mori said in a statement.
"The Australian government has a responsibility to make an independent evaluation of whether the military commission system meets with international legal standards."
Maj Mori asked the Australian government to publicly point to improvements made to military commissions since the prosecutors' emails were written last year.
He accused the government of accepting second class justice for its citizen.
"It is hard to understand how the Australian government can condone the trial of an Australian before a military commission, when the US government will not trust the freedom of a US citizen to the same process," he said.
Hicks, 29, was captured alongside Taliban fighters in Afghanistan in late 2001.
He has pleaded not guilty to charges of attempted murder, aiding the enemy and conspiracy.
A date for his trial has not been set but it could be heard within weeks.
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