Interrogator #1 told the court that he had used a variety of techniques detailed in the Army Field Manual on Interrogations against Omar Khadr, including those called "Love of Freedom", "Fear Up" and "Fear Up Harsh". He said he used "Fear Up Harsh" on several occasions:

"I got in his face, I screamed at him, I cursed because I knew he didn’t like it. I flipped a bench one time."

Interrogator #1 maintained that he had not physically abused Omar Khadr in any way. It nevertheless emerged in court that the same interrogator had been convicted in a court martial in 2005 of abusing another detainee in Bagram in 2002.

In this latter case, Interrogator #1 admitted twisting the bottom of a hood around the detainee’s neck, pulling the detainee toward him in a rough manner and sticking a water bottle in the detainee’s face and forcing him to drink from it.

Similar forms of abuse appear in Omar Khadr’s 2008 affidavit. For example, he said:

"On some occasions, the interrogators brought barking dogs into the interrogation room while my head was covered with a bag. The bag was wrapped tightly around my neck, nearly choking me and making it hard to breathe. This terrified me. On other occasions, interrogators threw cold water on me."

The most damning testimony at today’s hearing came when the defense asked Interrogator #1 directly if he had ever threatened the 15-year-old with rape if he did not cooperate. In his affidavit, Omar Khadr had alleged that

"On several occasions at Bagram, interrogators threatened to have me raped, or sent to other countries like Egypt, Syria, Jordan or Israel to be raped".

Interrogator #1 responded that he had told the teenager a "fictitious story" about a young Afghan who had lied and been sent to a US prison where "big black guys and big Nazis" noticed "this little Muslim" and, in their patriotic rage over the 9/11 attacks, the "poor little kid" was raped in the shower and died.

Interrogator #1 denied that he had ever directly threatened Omar Khadr with rape, and suggested that the story of the Afghan boy was legitimate under the authorized "love of freedom" and "fear up" techniques.

Speaking later at a press conference, lead defense counsel Barry Coburn variously described Interrogator #1’s revelation as "repulsive", "disturbing", "racist", "nauseous" and "offensive." He said he regarded it as a death threat levelled at Omar Khadr – "a 15-year-old boy who had been wounded and was lying on a stretcher" – and that, as far as he was concerned, it amounted to torture.

A defence motion filed in March for this hearing argues for the military judge to rule inadmissible certain statements made by Omar Khadr in custody that the government has said it will use against him. The motion argues that the statements should be suppressed because "they are the product of torture, involuntary, unreliable, do not serve the interest of justice, and are the fruit of the poisonous tree".

In the press conference today, defense co-counsel Kobe Flowers added that Interrogator #1’s statement went to the heart of the defense’s contention that Omar Khadr’s self-incriminating statements be excluded:

"The well was poisoned in this case back at Bagram – the prosecution can’t get away from it. Interrogator #1 brought that home to you today in full color."

There can be little doubt that the prosecution case suffered a major blow today.

In its written filing in March in relation to the defence suppression motion, the government wrote that "the accused was not tortured; nor subjected to cruel, inhuman, or degrading treatment".

At the hearing today, the prosecution did not contest Interrogator #1’s account.

Post script: Four journalists covering the Khadr are reported to have been banned by the Pentagon from covering future military commission proceedings on the grounds that they had allegedly violated rules by naming Interrogator #1 in their reporting.

The name of the former US Army Sergeant has long been in the public realm.