WASHINGTON -- The death of Osama bin Laden paints a clearer picture of the CIA's interrogation and detention program, revealing where it was successful and where its successes have been overstated.
At its core, the hunt for bin Laden evolved into a hunt for his couriers, the few men he trusted to pass his personal messages to his field commanders.
After the attacks of Sept. 11, 2001, detainees in the CIA's secret prison network told interrogators about one of al-Qaida's most important couriers, someone known only as Abu Ahmed al-Kuwaiti. He was a protege of al-Qaida's No. 3, Khalid Sheikh Mohammed.
In 2003, the CIA captured Mohammed, the group's operational leader. Mohammed was interrogated using what the agency called "enhanced interrogation techniques" such as sleep deprivation and the simulated drowning technique known as waterboarding.
Months after being waterboarded, Mohammed acknowledged knowing Kuwaiti, former officials say.
"So for those who say that waterboarding doesn't work, to say that it should be stopped and never used again: We got vital information, which directly led us to bin Laden," the chairman of the House Homeland Security Committee, Rep. Peter King (R-Seaford), said last week.
But current and former officials directly involved in the interrogation program say that's not the case.
Mohammed acknowledged knowing Kuwaiti after being waterboarded, but he also denied he was an al-Qaida figure or of any importance. It was a lie, much like the stories Mohammed said he made up about where bin Laden was hiding, those officials said. Even after the CIA deemed him "compliant," Mohammed never gave up Kuwaiti's real name or his location, or acknowledged Kuwaiti's importance in the terrorist network.
But the detention program did play a crucial role in the search for bin Laden.
In 2004, top al-Qaida operative Hassan Ghul was captured in Iraq. In a secret CIA prison, Ghul confirmed to the CIA that Kuwaiti was an important courier. In particular, Ghul said, the courier was close to Faraj al-Libi, who had replaced Mohammed as al-Qaida's operational commander.
The CIA had less success when it captured al-Libi.
Al-Libi was not waterboarded. But he did get the full range of enhanced interrogation, including intense sleep deprivation, former officials recalled. Despite those efforts, al-Libi adamantly denied knowing Kuwaiti. He acknowledged meeting with an important courier, but he provided a fake name.
Both he and Mohammed withheld or fabricated information, even after the agency's toughest interrogations. That gave credence to what many longtime interrogators have maintained, that increasingly harsh questioning produces information but not necessarily reliable information.
Given what they knew from other detainees, CIA interrogators suspected that al-Libi and Mohammed were lying about Kuwaiti and that it must be important if they were so committed to withholding this information. So they reasoned that, if they could find Kuwaiti, they might find bin Laden.
"They used these enhanced interrogation techniques against some of these detainees," CIA Director Leon Panetta said this past week. "But I'm also saying that, you know, the debate about whether we would have gotten the same information through other approaches, I think is always going to be an open question."