The question is why a CIA officer, Jose Rodriguez, mechanically shredded 92-hours worth of video of captives being waterboarded.
"It's not a pretty sight when you are waterboarding anybody or using any of these techniques, let's be perfectly honest," Rodriguez admitted.
"John Rizzo, the CIA's top legal counsel who oversaw the legalisation of the techniques in an exchange of memoranda with the Department of Justice, wanted to be certain that what was happening at the black site was in accordance with what had been legally agreed.
He had not anticipated that waterboarding would be used as often as it was. And he sent one of his most experienced colleagues to the black site, believed to be in Thailand, to find out.
Rizzo's colleague viewed all the 92 hours of video and concluded that the techniques were being legally applied, but he was uncomfortable about what he saw.
"He did say that portions of the tapes, particularly those of Zubaydah being waterboarded, were extraordinarily hard to watch," Rizzo told me.
Rodriguez knew the tapes were potentially a ticking time bomb and wanted to destroy them. He waited for three years with increasing exasperation at the apparent unwillingness of anybody on high to take responsibility for authorising their destruction.
Then when news of the CIA's secret black sites leaked, Rodriguez's patience ran out.
Why did Rodriguez destroy the recordings? Because they were proof of serious crimes, torture committed by the CIA and because those crimes undermine the very legitimacy of the tribunals now prosecuting those torture subjects. The tribunals are supposed to be "trying" the charges against these accused terrorists but, by refusing to allow any mention of the torture, the tribunals have themselves become prosecutorial. The whole thing is a sham.