By Jane Sutton

GUANTANAMO BAY U.S. NAVAL BASE, Cuba, Feb 14 (Reuters) - W hile the prisoners accused of plotting the Sept. 11 attacks were in the Guantanamo courtroom this week, guards seized confidential legal documents, books, photos and even toilet paper from their cells, a prison camp lawyer testified on Thursday.

Most of the seized items will be returned, the camp lawyer testified in a hearing marked by angry outbursts, eye-rolling and lengthy diversions from the docket in the war crimes court at the Guantanamo Bay U.S. Naval Base in Cuba.

Defense lawyers said some defendants returned to their cells after court sessions earlier in the week to find that bins containing their legal documents had been ransacked and confidential papers relating to their defense were missing.

The seizures happened while the camp's top legal adviser was on the witness stand giving assurances that no one was reading those private legal documents, said Cheryl Bormann, an attorney for defendant Walid Bin Attash.

Bin Attash, a one-legged man with a full beard and shoulder-length curls, stood and shouted to the judge, "In the name of God, there is an important thing for you ..."

The judge, Army Colonel James Pohl, told him several times to sit down, and threatened to have him removed from the courtroom. Bin Attash, who is accused of running an al Qaeda camp in Afghanistan where two of the hijackers trained, sat back down.

James Harrington, an attorney for defendant Ramzi Binalshibh said the document seizure created mistrust and made it nearly impossible to prepare a defense.

Navy Lieutenant Commander George Massucco, a prison camp lawyer, testified that guards were conducting routine safety inspections of the cells and grew concerned, apparently because the security stamps inked on the items were not all identical.

The stamps are applied by inspectors who clear the items for release to the detainees, and had apparently changed over the years. The guards, who rotate in and out of Guantanamo about once a year, apparently didn't know that, Massucco said.

In addition to the legal papers, guards seized a photo of Mecca, a copy of the U.S. government's "9/11 Commission Report" on the hijacked plane attacks, and a book written by a former FBI agent who is expected to testify in the defendants' trial. They also seized toilet paper on which Binalshibh had written notes in English.

"Based on my review, I've instructed the toilet paper to be returned to your client," Massucco told Binalshibh's lawyer.

Bormann suggested that, "There needs to be some guard force application of common sense and I don't know how the court instills that."

The judge also seemed frustrated that the guards were applying rules that seemed to change regularly.

One item of contraband will not be returned to Khalid Sheikh Mohammed, the alleged mastermind of the hijacked plane attacks on the World Trade Center and the Pentagon. Guards found a metal pen refill hidden in the binding of a book in his cell, Massucco said.

The defendants could face the death penalty if convicted of charges that include attacking civilians, conspiring with al Qaeda and murdering 2,976 people. The debate over the document seizures cut short testimony from the Pentagon appointee overseeing the Guantanamo war crimes tribunals, retired Vice Admiral Bruce MacDonald.

As "convening authority," he signed off on the charges and approved the decision to try the case as a death penalty case. Defense lawyers said he acted improperly by making that decision before all members of the defense teams had obtained the security clearances they needed to meet with the defendants and read classified documents.

MacDonald testified by videolink from Washington and got in a shouting match with one of the defense lawyers, Navy Commander Walter Ruiz, over whether various deadlines had been met. MacDonald is leaving his post in March after three years on the job but was expected to continue his testimony when the hearings resume in April.

Many other issues scheduled to be addressed this week were shunted aside to hear arguments on defense claims that the U.S. government is eavesdropping on confidential attorney-client conversations, a claim that prosecutors emphatically deny.

Follow us on Twitter @ReutersLegal | Like us on Facebook