The historic opening last week of U.S. military commissions that have not been used since World War II was marked by twists and turns and a carefully crafted defense strategy designed to bring the cases against suspected terrorists into the American court system.

While it is too early to tell whether they will be successful, military and civilian defense lawyers spent much of the week lambasting the commissions as legal relics and creating a record of what took place at the Navy base here for possible U.S. court review.

In the end, the attorneys are hoping that federal judges will agree with their central argument: that the suspected al Qaeda terrorists and Taliban fighters being tried in a makeshift military courtroom here cannot receive due process and fair trials under the commission process.

"These cases are headed straight to federal court," said Navy Lt. Cmdr. Charles Swift, appointed by the military to represent a man who served as Osama bin Laden's personal chauffeur. "They are making this up as they go along."

Commission officials and prosecutors dismissed the challenges. They said the commissions, created by President Bush two months after the attacks of Sept. 11, 2001, are designed to provide fair trials while protecting national security. Suspects receive key protections, they noted, including the rights to be considered innocent until proven guilty and to not be convicted unless prosecutors establish guilt beyond a reasonable doubt.

"More than anyone in the courtroom, I want a full and fair process," said Army Col. Robert L. Swann, the chief prosecutor of the commissions. "If there is a case on appeal, I want it sustained on appeal."

Last week, the military held the first hearings in what is expected to be a series of trials of suspected terrorists and Taliban fighters to be held before the commissions. The defense lawyers, most of them military officers appointed by the government, dominated the proceedings by questioning the legitimacy of the commissions, their rules and procedures, and the fitness of the men assigned to sit in judgment of their clients. They argued that Bush overstepped his authority by creating the commissions, that their clients' rights to speedy trials have been denied, and that the commissions violate the equal protection clause of the Constitution because only non-U.S. citizens can be tried before them.

Many of the points the defense lawyers tried to make may find their way before U.S. judges because they involve constitutional questions. So far, two of the four defendants formally charged have portions of their challenges already pending in federal court. A third challenge, in the case of an accused paymaster for al Qaeda, is about to be filed in U.S. court, according to his defense lawyer, Air Force Lt. Col. Sharon Shaffer. The case of a fourth man, who admitted in court on Thursday that he is a member of al Qaeda, is on hold while lawyers try to figure out whether he can represent himself or hire an attorney from his home country of Yemen.

Government lawyers dispute defense claims that the commissions are illegitimate. They say the president had the authority to create the commissions, that they borrow procedures from other international tribunals and that the rules do not violate the rights of the accused to receive fair trials.

Defense lawyers for two of the suspects this week questioned the qualifications of the presiding officer of the commissions, Army Col. Peter E. Brownback III, and the other officers appointed to the panel. Together, six commissioners, including Brownback and an alternate, will serve as judges and jurors during the trials. The defense lawyers were permitted to challenge the commissioners under voir dire as they tried to establish that the composition of the commission is fraught with potential conflicts that could undermine fairness.

For instance, the defense attorneys said Brownback, who served as a military lawyer and judge for 27 years before he came out of retirement to preside over the commissions, would exercise "undue influence" over the other commission members, who are military officers but not lawyers. When they gather to deliberate the cases, the defense attorneys argued, Brownback will have more influence over the proceedings because of his legal background.

The attorneys asked that he be removed from the case. Brownback said his departure would not satisfy the attorneys.

"The secretary of defense said there's going to be a lawyer on this thing," Brownback responded Wednesday during hearings in the case against David Hicks, an Australian accused of fighting alongside the Taliban. "You're objecting to the structure of the panel. It doesn't matter what I think. It's the structure. You can bounce me off, and they'll put on another lawyer."

Brownback said he will forward the challenge to retired Army Maj. Gen. John D. Altenburg Jr., who serves as the appointing authority of the commissions.

But the defense lawyers said that poses a conflict, too, because Brownback and Altenburg are "close personal friends." They said that the two have known each other since 1977, that Brownback's wife worked for Altenburg, and that Altenburg hosted Brownback's retirement ceremony in 1999.

The civilian attorney for Hicks, Joshua Dratel, asked Brownback whether he might be influenced by his relationship with Altenburg.

"A reasonable person who took the time to examine my record would say no," Brownback said. The defense lawyers also challenged the backgrounds and qualifications of four other commission members selected to serve on the panel.

Air Force Lt. Col. Timothy Toomey served as an intelligence officer in Afghanistan and Iraq. Marine Col. R. Thomas Bright supervised an operation that sent suspected terrorists and Taliban fighters to Guantanamo Bay. Marine Col. Jack Sparks Jr. lost one of his Marine reservists, a firefighter, in the attack on the World Trade Center. Army Lt. Col. Curt Cooper said he did not know precisely what the Geneva Conventions were and noted in a commission questionnaire that he was deeply affected by a visit to Ground Zero at the World Trade Center site.

"How are you supposed to separate that experience?" Dratel asked.

"They are separate things," Cooper said.

"How do you go about doing that?"

"I make no connection in my mind between these charges and my visit to the World Trade Center," Cooper said.

The lead prosecutor in the Hicks case said the commissioners could be fair and they should not be removed from the panel.

"We believe that none of these challenges should be granted," Marine Lt. Col. Kurt J. Brubaker said.

Brownback told the defense attorneys that he will forward to Altenburg the request to dismiss the commissioners. But the defense lawyers said that, too, poses a potential conflict. Altenburg was the officer who selected the commissioners in the first place.

On Friday, Altenburg said in a telephone interview that he could not discuss the challenges because he would have to rule on them. He said he has tried to distance himself from the proceedings -- he will not travel to Guantanamo -- so he can remain neutral when he rules on challenges and motions.

"We'll have to look at each one of these cases and make a decision: Do they in fact have too much involvement?" Altenburg said, referring to the defense contentions of conflicts on the commission.

The defense attorneys are also trying to establish that the rules of the commission are unclear, undermining the integrity of the trials.

On Thursday, an accused propagandist for al Qaeda, Ali Hamza Ahmed Sulayman al Bahlul, blurted out in the courtroom through an interpreter that he was a member of the terrorist organization. He was about to describe his relationship to the Sept. 11 attacks when Brownback cut him off.

The presiding officer then turned to the commissioners and told them to disregard al Bahlul's remark. It could not be considered evidence under the rules of the commission, he said. But prosecutors objected, saying such remarks could be admitted because there is no requirement to warn suspects against self-incrimination in commission rules.

"We note our objection to that statement," one prosecutor said.

After the hearing, Navy Lt. Susan McGarvey, a lawyer and spokeswoman for the commissions, said the prosecutors were correct and that the evidence could be admitted.

The defense attorneys issued a range of other objections, including that the translations provided to their clients were uneven at best.

Those assertions were included in an hour-long special aired Thursday throughout the Arab world on the television network al-Jazeera. A reporter for the network here, Mohammed Alami, asked Swann on Friday whether he was troubled that international observers and foreign governments were criticizing the commissions as unfair.

Swann defended the fairness of the commissions: "They're entitled to their opinion. I'm entitled to mine."

A U.S. soldier stands guard at the maximum security prison at Guantanamo Bay Naval Base in Cuba where those charged as enemy combatants are held.