Ali Soufan, testifying to a Senate panel behind a screen to hide his identity, said that his interrogation team obtained a "treasure trove" of information from Abu Zubaydah using a non-threatening approach that outwitted the detainee - even getting him to talk by using his childhood nickname.
Soufan said his team had to step aside when CIA contractors took over, using simulated drowning, sleep deprivation and other harsh methods. He said those techniques caused the prisoner to "shut down."
Soufan testified before a Senate Judiciary subcommittee, holding the first hearing on extreme interrogation methods since the Obama administration last month released Bush administration legal opinions that justified the techniques.
The hearing quickly became partisan when the panel's chairman, Sen. Sheldon Whitehouse, D-R.I., promised to unravel "our country's descent into torture" and vowed to expose "a bodyguard of lies" by the Bush administration.
Sen. Lindsey Graham, R-S.C., asked whether "we would have this hearing if we were attacked this afternoon."
Graham called the hearing a "political stunt," and said Democrats were trying to judge officials who - soon after the Sept. 11, 2001 terror attacks - "woke up one morning like most Americans and said, 'Oh my God, what's coming next.' "
Soufan countered that his personal experience showed that the harsh interrogation techniques didn't work even when there wasn't a lot of time to prevent an attack.
"Waiting 180 hours as part of the sleep deprivation stage is time we cannot afford to wait in a ticking bomb scenario," he said.
Soufan said the harsh techniques were "ineffective, slow and unreliable and as a result, harmful to our efforts to defeat al Qaeda."
Graham at times appeared irate, commenting at one point, "The people we're prosecuting didn't rob a liquor store."
He said former Vice President Dick Cheney has suggested there was "good information" obtained from the extreme methods. "I would like the committee to get that information. Let's get both sides of the story here," Graham said.
The South Carolina senator contended that Soufan didn't know all the information obtained from Abu Zubaydah.
Soufan responded that some Bush administration claims of success using harsh methods against Zubaydah were "half truths."
While Democrats want to highlight the view that the former administration tortured prisoners, their tactic has been overshadowed by a controversy involving the leader of the House of Representatives, Speaker Nancy Pelosi. Republicans have challenged her comments that in a briefing six years ago, she was not told the harsh tactics were being used.
Meanwhile, an administration official said Wednesday that President Barack Obama is seeking to block the release of hundreds of photos showing U.S. personnel abusing detainees on grounds that they would endanger American troops.
Also scheduled to testify is Philip Zelikow, who as a member of Condoleezza Rice's inner circle at the U.S. State Department, Philip Zelikow argued within the Bush administration that simulated drowning and other extreme interrogation techniques were illegal.
Zelikow learned of the then-classified Justice Department legal opinions in May 2005 and wrote a memo a few months later that contended the policies violated the U.S. Constitution.
More importantly, the memo was part of the internal arguments in the Bush administration that pitted the State Department against then-Vice President Dick Cheney and the Justice Department.
At times, Rice actively joined the dissent, a position that evolved from one of support after the Sept. 11, 2001 attacks. Cheney, to this day, contends the interrogations prevented terrorist attacks.
Rice ignited a controversy last month when she told Stanford University students, "If it was authorized by the president it did not violate our obligations under the convention against torture." But in an appearance in Washington afterward, Rice said she really meant "the president (George W. Bush) said, 'I won't authorize anything that is illegal."
Zelikow argued in his 2005 memo that constitutional protections for defendants, and the Constitution's ban against cruel and unusual punishment, were violated by some of the interrogation tactics.
Writing last month for the Internet site of Foreign Policy Magazine, Zelikow said, "In other words, Americans in any town of this country could constitutionally be hung from the ceiling naked, sleep deprived, water-boarded, and all the rest - if the alleged national security justification was compelling."
Zelikow, who served as counselor to Rice at the State Department from February 2005 through January 2007, circulated his 2005 memo within the administration but had no authority on legal matters beyond the power of persuasion. He did not get far.
"My colleagues were entitled to ignore my views," he wrote. "They did more than that. The White House attempted to collect and destroy all copies of my memo."
Several members of Congress have asked the Obama administration to search for a copy.
Zelikow, in an interview with The Associated Press, said that he told Rice that he was circulating a dissent.
"I would keep her informed about everything," he said. "I suspect I provided her a copy of the memo. In general, she understood the broad thrust of what we in the State Department were trying to do. She, at her level, was working and finding a way for the president to change the policies."
A former senior State Department official under Rice, who declined to be quoted by name in discussing the internal dispute, said the secretary held regular meetings on detainee issues with her small inner circle. In those meetings, he said, she supported efforts to close the detainee prison at Guantanamo, empty the secret detention sites and accept international standards for treatment of detainees.
In February 2007 Rice's legal adviser, John Bellinger III, wrote his own dissent. He concluded that some of the tactics violated international treaties including the Geneva Conventions prohibiting torture.