A key question which remains unresolved after the furore over the photos of alleged Iraqi prisoner abuse is to what extent the breaking of prisoner morale is still part of American policy.
The man brought in to run the Abu Ghraib prison is Maj Gen Geoffrey Miller, the man who ran the US detention facility at Guantanamo Bay, Cuba.
The big question is whether this behaviour stemmed from an accepted policy (AP Photo/Courtesy of The New Yorker)
He told reporters who were shown the prison near Baghdad that sensory deprivation methods would now be used only after a general had "signed off" on them.
"We will examine very closely the more aggressive techniques," he said. But he did not say they would be stopped.
Yet he also said on Saturday that the Geneva Conventions would be applied in Iraq - they are not in Guantanamo though the Pentagon says their "spirit" is respected.
The Geneva Conventions are designed to protect prisoners of war from inhumane treatment.
On Saturday Gen Miller referred to the Fourth Geneva Convention, which applies to the protection of civilians in wartime.
Both it and the Third Geneva Convention, also drawn up in 1949, but this time to cover prisoners of war, lay down a series of measures to ensure that protection.
Importantly, both state that prisoners must "be treated humanely at all times".
Gen Miller is not new to Abu Ghraib. Last summer he was brought in to review the handling of prisoners there. His findings are revealed in the report this year by Maj Gen Antonio Taguba into abuses at Abu Ghraib.
The report uses euphemisms as it describes Gen Miller's conclusions. But the meaning is clear enough - prisoners have to be prepared for questioning.
"MG Miller's team focused on three areas: Intelligence integration, synchronisation, and fusion; interrogation operations; and detention operations.
"The principal focus of MG Miller's team was on the strategic interrogation of detainees/internees in Iraq. Among its conclusions in its Executive Summary were that CJTF-7 [the US army in Iraq] did not have authorities and procedures in place to affect a unified strategy to detain, interrogate, and report information from detainees/internees in Iraq. The Executive Summary also stated that detention operations must act as an enabler for interrogation."
The words "integration", "synchronisation", "fusion" and the phrase "enabler for interrogation" must mean the process by which the detention officers prepare the prisoners for questioning by subjecting them to demoralising techniques.
There is more.
"MG Miller's team stated that the function of Detention Operations is to provide a safe, secure, and humane environment that supports the expeditious collection of intelligence. However, it also stated "it is essential that the guard force be actively engaged in setting the conditions for successful exploitation of the internees".
Did the guard force at Abu Ghraib who liked to take pictures of themselves at work simply overstep the mark while following a general instruction to set the "conditions for successful exploitation of the internees"?
Claims of accused
Evidence that it is all part of policy has come from one of the soldiers seen in the photos. Specialist Sabrina Harman of the Military Police was pictured smiling behind a pyramid of naked prisoners.
She is quoted in the Washington Post as saying in an e-mail that the aim was to break down the prisoners for interrogation.
"If the prisoner was co-operating, then the prisoner was able to keep his jumpsuit, mattress, and was allowed cigarettes on request or even hot food. But if the prisoner didn't give what they wanted, it was all taken away until [military intelligence] decided," she wrote.
"The job of the MP [military police] was to keep them awake, make it hell so they would talk."
Gen Miller insists the Geneva Conventions are being fully adhered to now
The whole issue of interrogation is now under examination by yet another investigation, this time led by Maj Gen George Fay.
And as US Defence Secretary Donald Rumsfeld himself said during Friday's Congressional hearings into the alleged abuse, there is more to come.
During the hearings Republican Senator Lindsey Graham warned that the further revelations might concern "rape and murder".
It was striking that only one senator, the senior Democrat Carl Levin, asked Mr Rumsfeld about this. Many others chose to use most of their time making speeches, as often happens in Senate hearings.
Mr Levin identified the problem. The photos, he suggested, did not show a few "bad apples" infecting the rest of the barrel, but the application of a policy.
One is reminded of the calamitous effect of the British treatment of IRA suspects during internment without trial in the early 1970s.
The British army put into practice so-called "sensory deprivation" techniques designed to break down a prisoner's resistance before and during interrogation.
Those techniques involved isolation, subjection to white noise, hooding, sleep deprivation and physical hardship, such as being kept standing or keeping arms spread out.
When news of these methods came out, as they did quite quickly, there was an uproar and the IRA was handed a new recruiting sergeant.
The CIA and the US military developed similar coercive techniques. An American manual describing some of them and called "Human Resource Exploitation Training Manual - 1983" was released under the US Freedom of Information Act in 1997.
The methods included the threat of force on relatives, blindfolding and the stripping of prisoners naked.
The methods used in Abu Ghraib have added in sexual humiliation, presumably regarded by the guards as particularly effective in the Arab world.
US and British soldiers are regularly subjected to the techniques themselves to help enable them to resist interrogation. It is known in the trade as R2I - resistance to interrogation.