Prosecutors have found secret movies of guards forcibly eradicating the accused mastermind of the bombing of the Navy destroyer Cole from his cell at Guantánamo Bay across the time federal brokers declare he voluntarily confessed to his function within the Qaeda plot, the lead prosecutor informed the trial decide on Wednesday.

The shock disclosure might trigger extra delays in Guantánamo’s longest-running death-penalty case, which has been in pretrial proceedings since 2011. The decide is retiring from the Army and has scheduled closing arguments for next week on the query of whether or not to permit 2007 statements by the defendant, Abd al-Rahim al-Nashiri, at his eventual trial.

But the videotapes haven’t been turned over to both the decide or protection attorneys. Instead, a prosecutor, Michael J. O’Sullivan, stated the tapes had been so delicate that authorities brokers had been making ready them for screenings in categorised settings — after sure info was apparently obscured.

Agents have testified that in January 2007 Mr. Nashiri boasted of his function within the Cole assault, which killed 17 sailors off Yemen in October 2000. But protection attorneys have lengthy argued that he informed federal brokers what he thought they wished to listen to as a result of he had earlier been tortured.

On Wednesday, Mr. O’Sullivan stated authorities officers screened the primary of as much as 17 movies this week for protection attorneys after some type of secret processing he wouldn’t describe in open court docket. At least a few of them confirmed Mr. Nashiri being pressured out of his cell in late 2006 and early 2007, across the time of his interrogations, Mr. O’Sullivan stated.

The method has usually been carried out on the Guantánamo jail by seven specifically educated guards in black riot gear, their faces obscured, who put a defiant prisoner face down on the bottom after which in restraints. In 2017, the prison published photos of troopers coaching on easy methods to do it.

Annie W. Morgan, considered one of Mr. Nashiri’s attorneys, stated the one video the protection attorneys have been allowed to see confirmed guards chopping shackles off the prisoner’s ankles eight days earlier than his 2007 interrogations, however none of him being shackled and faraway from his cell.

Defense attorneys initially requested for movies of the prisoner’s therapy in Camp 7 in 2011, when he was charged, the decide stated in a ruling final 12 months. Prosecutors had replied that there have been none.

Then, greater than a 12 months in the past, Mr. Nashiri’s attorneys noticed an entry in a jail logbook describing how guards lower shackles off the prisoner’s ankles as a result of a key had damaged off inside, and {that a} particular unit of army cameramen had been referred to as. They then requested prosecutors for any video of the episode.

On June 16, Ms. Morgan stated, the prosecution disclosed the existence of greater than a dozen movies, together with the one exhibiting the ankle shackles being eliminated.

In searching for a video of that encounter, prosecutors apparently discovered the others.

Ms. Morgan stated Guantánamo jail data in 2006-7 confirmed that Mr. Nashiri was “subjected to an increasing number” of pressured removals from his cell simply earlier than his interrogations. She referred to as it “a deliberate attempt to remind him of the harsh treatment he received in C.I.A. black sites and what would happen if he did not cooperate.”

In the black websites, company staff waterboarded him, confined him to a picket field, threatened him with dying and had him shackled in painful positions to achieve his cooperation. He was saved in isolation and at occasions abused rectally.

While Mr. Nashiri was in Thailand in 2002, the C.I.A. made videotapes depicting the therapy of him and one other prisoner often known as Abu Zubaydah, however then destroyed them three years later. In place of that destroyed proof, the movies of Mr. Nashiri at Guantánamo’s Camp 7 jail in 2006 and 2007 “will give at least a glimpse into that behavior,” Ms. Morgan stated.

The decide requested the prosecutor for the nationwide safety justification for withholding copies of the tapes from the judiciary and the protection, and instructed in open court docket that it was maybe the necessity to shield “tactics.”

Mr. O’Sullivan responded: “It’s been cleared for display only. That’s about all I can tell you at this point.”

Once the movies had been processed, he stated, prosecutors would supply categorised screenings on a rolling foundation, maybe starting as early as subsequent week.