The former officials said the CIA interrogators’ refusal was a factor in forcing the Bush administration to act earlier than it might have wished.
When Mr Bush announced the suspension of the secret prison programme in a speech before the fifth anniversary of the September 11 terror attacks, some analysts thought he was trying to gain political momentum before the November midterm congressional elections.
The administration publicly explained its decision in light of the legal uncertainty surrounding permissible interrogation techniques following the June Supreme Court ruling that all terrorist suspects in detention were entitled to protection under Common Article Three of the Geneva Conventions.
But the former CIA officials said Mr Bush’s hand was forced because interrogators had refused to continue their work until the legal situation was clarified because they were concerned they could be prosecuted for using illegal techniques. One intelligence source also said the CIA had refused to keep the secret prisons going.
Senior officials and Mr Bush himself have come close to admitting this by saying CIA interrogators sought legal clarity. But no official has confirmed on the record how and when the secret programme actually came to an end.
John Negroponte, director of national intelligence, who was interviewed by Fox News on Sunday, said in response to a question of whether CIA interrogators had refused to work: “I think the way I would answer you in regard to that question is that there’s been precious little activity of that kind for a number of months now, and certainly since the Supreme Court decision.”
In an interview with the Financial Times, John Bellinger, legal adviser to the state department, went further, saying there had been “very little operational activity” on CIA interrogations since the passage last December of a bill proposed by Senator John McCain outlawing torture and inhumane treatment of prisoners.
Mr Bellinger said the secret prisons remained empty for the moment. But he defended the US position that use of such prisons did not contravene international conventions as some in Europe have argued. He also said that, theoretically, the Pentagon as well as the CIA had the legal right to run such facilities. The CIA declined to comment.
Key figures among the 14 prisoners transferred to Guantánamo, including Khalid Sheikh Mohammed, had been held in secret centres for three years or more.