WASHINGTON – A federal appeals court yesterday questioned whether a Guantanamo Bay Naval Base detainee has a right to be present for his entire trial, giving the Bush administration hope it may use military commissions to try prisoners there.

The three-judge panel reacted strongly when a lawyer for Salim Ahmed Hamdan told them “it makes no sense to say that we adhere to international law and the first thing we do at the beginning of a trial is violate a canon of international law.”

Legal systems of other countries don’t allow a defendant to be present for all parts of a trial, Appeals Judge Raymond Randolph replied. Judge John Roberts added that some countries don’t allow cross-examination of witnesses.

“This is the law in Rwanda,” but should not be in America, replied the detainee’s lawyer, Charles Swift.

The question is crucial to the future of the government’s military commissions, which President Bush authorized shortly after the September 11, 2001, attacks to deal with alleged terrorists and their associates. Much of the evidence in military commission cases likely would be classified and the government does not want the defendants to have access to it for national security reasons.

Mr. Hamdan, who was a personal driver for Al Qaeda terrorist leader Osama bin Laden, won a favorable ruling in November from U.S. District Judge James Robertson, a President Clinton appointee who brought the military commissions to a halt by saying their procedures were unlawful.

Last November’s ruling is “an extraordinary intrusion into the executive’s power” to defend America, the government said. At the heart of the legal battle is the fact that Mr. Bush has declared international treaty protections do not apply to Mr. Hamdan and all others deemed by the American government to be linked to Al Qaeda.

The judge’s decision five months ago halted the trial of Mr. Hamdan, who joined Mr. bin Laden in 1996, the government says, serving as his personal driver and delivering weapons and ammunition to Al Qaeda.

Mr. Hamdan’s lawyers say he is an innocent civilian who was not part of Al Qaeda and whose only crime was working for a very bad employer. A driver and mechanic with a fourth-grade education, Mr. Hamdan left his home country of Yemen to find a better job, his lawyers say, and he was captured by bounty hunters in Afghanistan, sold to the Americans and shipped to Guantanamo Bay, Cuba.