The CIA paid $80m (£51m) to two psychologists with no background knowledge of al-Qaeda or counterterrorism to help develop the "enhanced interrogation techniques" the agency used against terror suspects.
According to a damming report by the Senate Intelligence Committee which condemned the CIA's "brutal" interrogation techniques, the agency paid two contractors for their involvement in carrying out the torture methods.
Although the report does not name the contractors, NBC News has previously identified them as Mitchell Jessen & Associates - a Washington based company run by two psychologists, Dr John "Bruce" Jessen and Dr James Mitchell, who had both previously worked with the US Air Force.
Jessen and Mitchell were reportedly paid to help develop the torture programme in 2002 as well as personally conduct some of the most important interrogations.
This was despite, as the report states, the fact that neither psychologist "had any experience as an interrogator, specialised knowledge of al-Qaeda, a background in counterterrorism, or any relevant cultural or linguistic expertise".
After hiring the pair, the CIA are said to have researched a "list of exploitation and interrogation techniques that had been effective against Americans" used during Survival, Evasion, Resistance Escape [SERE] training, a US Defense Department agency that taught special operations forces how to survive torture.
Working with Jessen and Mitchell, the CIA soon came up with a list of 10 techniques to use against the terror suspects, including waterboarding, sleep deprivation and carrying out mock executions.
The report states the contractors "developed the list of enhanced interrogation techniques and personally conducted interrogations of some of the CIA's most significant detainees using those techniques."
It added: "The contractors also evaluated whether the detainees' psychological state allowed for continued use of the techniques, even for some detainees they themselves were interrogating or had interrogated."
The report adds the pair were originally supposed to receive more than $180m for their help, but only received $80m when their contract was terminated in 2009.
Elsewhere, people with no specialist training or expertise, some of whom had histories of violence, were also found to be carrying out CIA-led interrogations on terror suspects.
The report said: "CIA employed people who had 'personal and professional problems of a serious nature' - including histories of violence and abusive treatment of others. The report found that that should have called into question their employment, let alone their suitability to participate in the sensitive CIA program."