A risky move by one of the defense teams has led to unusual drama in the seemingly-endless pre-trial proceedings of the 9/11 war crimes case.

Defense attorney Walter Ruiz decided to roll the dice and challenge the prosecution to prove that his client, alleged 9/11 money man Mustafa al Hawsawi, should be tried as a war criminal.

Ruiz' argument was as audacious as it was simple: namely, that the U.S. was not at war with al-Qaida on 9/11, and that Hawsawi thus should not and cannot be tried by this military tribunal.

The Guantanamo war court case at the controversial American navy base on Cuban soil has slogged through five-and-a-half years of pre-trial hearings. Last week's was the 26th.

Khalid Sheik Mohammed, alleged mastermind of the 9/11 attacks, and his four co-defendants are charged with war crimes punishable by death for allegedly helping nineteen airliner hijackers kill nearly 3,000 people on Sept. 11, 2001.

U.S. Army Col. James Pohl, the judge who presides over this massive case, found that Ruiz's motion challenging the court's jurisdiction "raised a colorable issue" - meaning it was plausible for the court to consider.

The other four defense teams plan to make similar challenges on behalf of their clients, with several holding off until obtaining more of the classified documents they're seeking from the prosecution.

But lawyer Ruiz is a man in a hurry. He's often expressed impatience with this military commission tribunal's glacial pace. The commission was created by Congress in 2009 specifically to try Guantanamo captives, including the five accused of plotting the 9/11 attacks.

Much of the delay in reaching the trial stage — Pohl has yet to set a trial date — stems from the defense teams' repeated attempts to wrest secret records of their clients' confinement in now-defunct CIA lockups.

A Senate Intelligence Committee investigation determined all five were brutally interrogated in a network of overseas secret CIA prisons known as "black sites" before being turned over to the U.S. military.

An audacious gamble

On day two of last week's five-day session, Ruiz brandished in court the first fruits of his legal gambit. They had arrived after 9 p.m. the night before: newly declassified documents he'd requested more than four years ago.

Among them were copies of handwritten notes of Hawsawi's four-day interrogation conducted by two FBI agents and a Pentagon official in early 2007, several months after his transfer to Guantanamo from one of the black sites.

The notes amounted to a documentary record of Hawsawi's so-called "clean team" interrogation. It was done to gather war court-admissible evidence, since any coerced statements he might have made in CIA captivity would be barred by the 2009 Military Commission Act.

Statements made by Hawsawi during that "clean team" interrogation could be used by government prosecutors to argue that al-Qaida was at war with the U.S. on 9/ll and that he was part of that organization.

For Ruiz, obtaining the memo outlining the conditions under which that interrogation was conducted could bolster his contention that anything said in those interviews was tainted by CIA interference. That would play into a larger goal of having that interrogation "suppressed" — that is, made inadmissible as evidence.

Those two FBI agents, one now retired, who conducted that interrogation were both at the war court as witnesses for the prosecution. Cross-examining them, Ruiz established that the interview with Hawsawi, whose native tongue is Arabic, had been conducted entirely in English with no lawyer present, with Hawsawi's feet shackled to the floor and without any audio or video recordings having been made of the sessions.

The interrogation took place in a structure known as Camp Echo II. It's recently been used by defense lawyers to meet with their clients. The five defendants are actually imprisoned elsewhere, in a top secret lockup called Camp Seven whose precise location at Guantanamo remains classified.

Camp Echo II had long been suspected of being used by the CIA as a black site in the island prison camp's early years. FBI special agent Michael Fitzgerald's newly revealed notes of Hawsawi's interrogation at Camp Echo II suggested the 49-year-old Saudi may have been held there earlier. Twice Fitzgerald wrote cryptically that Hawsawi may recognize his surroundings from the past.

Ruiz also obtained on the eve of the cross examination a long-sought memo laying out the ground rules for the FBI's interrogations. For him and the other defense teams, the memo confirmed what they had long suspected: that those "clean team" interrogations may have been tainted by the CIA's say over how they were carried out.

CIA sets the rules for FBI interrogations

That six-page memo, issued by the Office of the General Counsel for the FBI's National Security Law Branch, was dated Jan. 10, 2007. It was the day before now-retired FBI special agent Abigail Perkins, the other witness for the prosecution, was to begin interrogating Hawsawi.

FBI agents conducted clean team interrogations of those captives previously held at CIA black sites. The agents were instructed in the memo that any mention made by such a prisoner of "the interrogation techniques previously used on him and his detention locations" were "deemed by the CIA to be national security information."

The CIA would also have control over the documentation of the FBI's interrogation.

"The interviewing agent should document the interview in an FBI letterhead memorandum (LHM) prepared on a CIA-supplied laptop," the memo stipulated. Noting that there would have to be a thumb-drive memory chip for each interrogated captive, it also required that the draft LHM be transmitted electronically and that the agent's notes be delivered to the CIA for classification review.

"If the detainee alleges misconduct prior to his detention and/or techniques used during interrogations prior to his arrival at GTMO," the memo continued, using the military abbreviation for the U.S. navy base, "those allegations should be documented " on the CIA-supplied laptop "on a daily basis." (emphasis in the original)

It also required that the FBI interrogator team put any information the CIA deemed "compartmented" – i.e., mistreatment during prior interrogations or disclosure of detention locations – in a second, separate memo and keep such information out of the original memo.

The memo also promised that FBI interrogators would be given background briefings – no mention by whom — on captives they would be interrogating.

"The agents will also be given limited access to CIA databases containing intelligence reports that were previously disseminated to the intelligence community," the memo continued. "Review of these materials will be at the discretion of the interviewing agent in preparation of the interview."

The FBI interrogators were also instructed to clear with unspecified spy agencies any questions about the captive's previous detention.

"No statement made by a detainee while that detainee was in the custody of an intelligence agency, or any evidence obtained as a result of such statement, will be used in an interview," the memo admonished, "unless approved in advance by the assigned prosecutor and the appropriate intelligence agencies."

Former FBI special agent Perkins told the war court she had, in fact, "reviewed" CIA cables documenting statements Hawsawi may have made while in CIA detention. But Perkins added that she had not relied on them to prepare for her interrogation of the suspected money man in the 9/11 plot.

That did not satisfy Judge Pohl.

"You said you didn't rely on them," he said, as he turned to Perkins in the witness stand. "The question is: did you use any of the CIA statements in preparing your interview of Mr. Hawsawi?"

Perkins replied it would be hard for her to distinguish between reviewing and using the CIA cables. "Having them in my mind, sir," she told the judge, "may have influenced me, so I can't disassociate completely."

There is little doubt Ruiz will use Perkins' statements if and when this case comes to trial. His aim would be to suppress as CIA-tainted evidence whatever his client told the FBI agents in the "clean team" interrogation.

And that may be what the move to challenge the war court's jurisdiction over Hawsawi was really about: not so much a long-shot bet on a military tribunal ruling that the U.S. was not, in fact, at war with al-Qaida on 9/11, but rather a ploy to force the prosecution to turn over long-withheld potential evidence of government misconduct toward his client.

Prosecutors fight back in dramatic fashion

Government prosecutors seized on Ruiz' challenge to make their case that al-Qaida and the U.S. were at war at the time of the 9/11 attacks.

For the first time in years of pre-trial proceedings, jarring video recordings capturing the actual attacks on the World Trade Center and the Pentagon were played in the courtroom.

Khalid Sheik Mohammed watched from his front row seat while a handful of relatives of those killed – invited guests of the U.S. government — watched from behind three layers of glass in a partition at the back of the courtroom.

"It was very emotional, I did break down in there," said Michael Salamone, whose brother John worked at Cantor Fitzgerald on the 104th floor of the World Trade Center's north tower and perished on 9/11.

"It wasn't a TV show anymore – at that moment in time, it really was these real people: these were the people that murdered my brother and a lot of other people."

Dozens of bank documents were also shown to the courtroom, all alleged by government prosecutors to show Hawsawi's financing of the 19 hijackers.

James Connell leads the team defending Khalid Sheik Mohammed's nephew, Ammar al Baluchi. A lawyer with experience handling other death penalty cases, he plans to mount his own challenge to the war court's jurisdiction at a pre-trial hearing scheduled for March.

"We've always known that the personal jurisdiction hearing was going to look like a mini-trial," Connell said after this latest court session, "and that's what we saw this week."

For Connell, that "mini-trial" amounted to a contest between evidence and testimony from the prosecution that were fully expected and one unanticipated revelation after another coming from the defense.

"It's no surprise that the prosecution played videos of planes crashing into towers or the terrible suffering afterward; the evidence that they produced on paper, essentially financial documents, was no surprise to us either," he said of the government's presentation.

The same could not be said about the documents Ruiz obtained as evidence.

"We never knew about the instructions that went to the FBI agents about how to do the interrogation, we never knew about the connection between the CIA database and FBI preparation for the interrogations," Connell told NPR. "So we did learn some things that had never been in the public before — and we on the defense didn't know."

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