The US intelligence community has unleashed a vigorous defence of its work in fighting terrorism, with the CIA releasing documents and former officials making impassioned arguments to challenge a Senate committee's findings that the agency had tortured detainees in the aftermath of September 11. Current and former CIA officials went on a media blitz to ensure their side was included in the debate sparked by the release of a report that found that the CIA's detention and interrogation programme was more brutal than portrayed and did not yield information to thwart attacks. We part ways with the committee on some key points CIA DIRECTOR JOHN BRENNAN In a series of television interviews, newspaper columns and online forums, CIA officials and sympathisers offered variations of the same basic rebuttals: that the harsh techniques were authorised under the law, effective in gleaning intelligence and known to and approved by officials in Washington who were briefed dozens of times. CIA director John Brennan acknowledged in a statement that "the detention and interrogation programme had shortcomings and the agency made mistakes". But while the CIA had "common ground" with some findings, Brennan said "we part ways with the committee on some key points". He said intelligence gleaned was used to disrupt attack plans, capture terrorists and save lives. And he baulked at the conclusion that CIA officials had tried to hide the extent of the programme. "While we made mistakes, the record does not support the study's inference that the agency systematically and intentionally misled each of these audiences on the effectiveness of the programme," the statement said. The CIA received some backup from the six Republicans on the Intelligence Committee. They issued a "minority report", complaining that the Democratic-driven probe had cost taxpayers more than US$40 million and "diverted countless CIA analytic and support resources". The Republicans also said the findings were riddled with errors and rife with political bias. Committee staffers never interviewed a single witness, they said, and failed to correct factual and analytical mistakes identified by a CIA review in June 2013. Intelligence officials agreed that the CIA was overwhelmed by the scope of the detention and interrogation effort, resulting in "significant lapses in the agency's ability to develop and monitor its initial detention and interrogation activities". The agency also agreed that it did not have enough interrogators with vital language skills or enough experience handling and interrogating detainees. In the rebuttal, the CIA complained that the Senate report exaggerated how often and for how long unapproved and "improvised" techniques continued, arguing only "isolated cases" were reported after the introduction of new guidelines in 2003. Those cases were reported and investigated, sometimes even by the Department of Justice. The CIA said the report overstated how often unauthorised techniques were used, because some methods - such as cold water dousing and sleep deprivation - "were categorised as standard techniques at the time and did not require headquarters' permission for each use". On the matter of whether useful intelligence could have been obtained by other methods, the CIA simply dismisses the question as "unknowable". The CIA was most emphatic when defending the value of the intelligence gleaned from detainees who endured sleep deprivation, waterboarding and threats of sexual assault or death. The agency said such interrogations were vital to obtaining information that had prevented attacks and led to the capture of high-profile terrorists, such as self-proclaimed 9/11 mastermind Khalid Sheikh Mohammed.