US offers tapes from wiretapped Guantánamo prison as evidence in September 11 case

The government has released a secret intelligence program that clandestinely recorded prison yard conversations of Khalid Shaikh Mohammed, accused of masterminding the September 11, 2001, attacks, as prosecutors try to provide evidence at any trial can be used. .

The move comes as prosecutors have considered new ways to refute defense lawyers’ claims that CIA torture tainted the subsequent FBI interrogations of Mr. Mohammed and his accused accomplices to extract confessions that the government considered key evidence considered in the process. It also sheds light on a wiretapping operation whose existence has never been formally acknowledged until now.

This week, an Iraqi-American translator for the FBI vouched in court for a transcript from Mr. Mohammed describing how he learned when the hijackers would strike. It came in a coded message, according to a snippet of the transcript shown in court: “Your friend so and so will be getting married on September 11.”

The conversation was captured on a nearly hour-long recording of Mr. Mohammed speaking to another detainee at Guantánamo Bay on October 23, 2007. Under a secret prison program, more than a dozen suspected terrorists, subjected to years of solitary confinement and torture by the CIA, were given an hour of recreational time within earshot of another isolated prisoner.

By then, Mr. Mohammed was approaching a five-year prison sentence without charges or a lawyer. He was waterboarded for years, sexually humiliated, deprived of sleep and interrogated by American interrogators, including by FBI agents in 2007.

Now, 16 years later, the recording on the prison grounds has been made public.

The timing coincides with efforts by prosecutors in the September 11 case to strengthen their evidence following a damaging ruling in the other death penalty case at Guantánamo, the Cole case. Both cases are in pretrial proceedings and no date has been set for jury selection as military judges decide what evidence can be used at a trial.

In August, a judge in the Cole case excluded confessions made by the defendant, Abd al-Rahim al-Nashiri, during FBI war prison interrogations in 2007. The judge concluded that the confessions were the result of torture, a decision that undermined a foundation. prosecution strategy in Guantanamo military commission cases.

The government will appeal the ruling. But in response, prosecutors in the September 11 case told their judge, Col. Matthew N. McCall, that they would call more witnesses next year to strengthen their case that Mr. Mohammed and his co-defendants had voluntarily incriminated themselves during interviews . with FBI agents in 2007.

It was then announced in court this week that the secret eavesdropping program had been released. Lawyers revealed that a government intelligence operation had secretly collected conversations in which one inmate shouted at another during recreation periods. It is not known when the operation ended, if at all.

The program itself was hinted at, but not formally acknowledged. During a decade of pretrial hearings, government witnesses sometimes mysteriously mentioned the existence of transcripts of “conversations” but never disclosed how they were obtained.

James G. Connell, a lawyer for Mr. Mohammed’s cousin Ammar al Baluchi, who is a defendant in the case, said he would challenge the admissibility of the audio recordings because they are from cruel, inhuman and degrading therapy.

From 2006 to 2009, he said, prisoners were held in solitary confinement and each person was allowed to speak to only one other inmate during an hour’s reprieve from their high-security cells.

At the time, prisoners in the custody of a special unit known as Task Force Praetorian or Task Force Platinum were given recreation time in specifically designated pairs. They were locked in separate enclosures, which meant the prisoners could shout back and forth but could not see each other.

Mr. Connell called the recordings the product of a government-devised system of solitary confinement that for years gave inmates “a single outlet to communicate with another human being.” The government had then “exploited” it for pilot purposes, he added.

A senior FBI official, Jacqueline Maguiresaid in testimony last week that she believed the recreation grounds were bugged “for violence protection purposes,” mainly to listen to inmates to protect prison staff.

In Mr Mohammed’s case, his recreational partner was Guled Hassan Duran. Mr. Duran, a Somali national, was captured in Djibouti in March 2004 and held by the CIA before being transferred to Guantanamo in September 2006. He has never been charged with a crime.

In the part of their conversation shared in court this week, Mr Mohammed explained that he had learned that the September 11 attacks were going to happen from a visitor “who came to my house in Kandahar” in Afghanistan.

From there, he said, he went to visit “the sheikh,” an apparent reference to Osama bin Laden, to deliver the message. “There were 20 days left,” Mr. Mohammed said, according to the transcript. “We were on August 20 or so.”