Five men accused of orchestrating the Sept. 11 attacks, including the self-proclaimed mastermind, are headed back to a military tribunal for their arraignment at Guantanamo Bay on Saturday.

This time the defendants may put up a fight.

Khalid Sheikh Mohammed, who told military authorities that he was responsible for the planning of the terror assault “from A to Z,” previously mocked the tribunal and said he would welcome the death penalty. His co-defendant, Ramzi Binalshibh, told the court that he was proud of the attacks.

But Jim Harrington, the civilian lawyer for Binalshibh, said the defendants are expected to fight the charges against them, which include murder and terrorism and carry a potential death penalty.

“He has no intention of pleading guilty,” Harrington said. “I don’t think anyone is going to plead guilty.” Harrington declined to say what would be the basis of his defense and lawyers for Mohammed did not respond to messages seeking comment.

The men never entered formal pleas in previous hearings, but Mohammed told the court that he would confess to planning the attacks and hoped to be a “martyr.” He dismissed the military justice system, saying, “After torturing, they transferred us to inquisition land in Guantanamo.”

Now after three years in which the tribunals known as military commissions have been reformed by Congress and the president, they’ve had time to reconsider their defense.

“I’m not sure they really understood the ramifications of it at that time,” Harrington said.

The arraignment Saturday, before an audience that includes a handful of people who lost family members in the Sept. 11 attacks as well as journalists and human rights observers, will be followed by a hearing on a series of defense motions that challenge the charges and the extreme secrecy rules imposed to prevent the release of information about U.S. counterterrorism methods and strategy. The start of their actual trial is at least a year away.

The five defendants are held in a section of Guantanamo that is under such tight security even its exact location on the base is classified, a prison-within-a-prison known as Camp 7. They have not been seen in public since the day after Obama’s inauguration, when the commission held a hearing to continue their case.

New rules adopted by Congress and Obama forbid the use of testimony obtained through cruel treatment or torture. The defendants were held at secret CIA prisons overseas where they were subjected to what the government called “enhanced interrogation techniques.” Mohammed was waterboarded 183 times, officials have said.

The government has pledged to make the proceedings more transparent, broadcasting hearings to several U.S. military bases in the Northeast so that families of Sept. 11 victims and others can monitor the trial without going to Guantanamo.

News cameras, however, are still not permitted inside the courtroom, where the media and other observers are kept behind double-paned, soundproof glass. Lawyers for the defendants had opposed the government’s plan to show the hearings by closed-circuit TV to bases in the U.S., arguing that they should be broadcast to everyone.

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