Ghul, a Pakistani, was arrested in mid-January 2004 in northern Iraq carrying a letter addressed to bin Laden from al Qaeda's leader in Iraq urging that he be allowed to embark on a full-scale war against Iraq's Shia population.

Ghul obviously had access to al Qaeda's inner circle in Pakistan and so was taken to a secret CIA prison in eastern Europe, where he was subjected to a variety of coercive interrogation techniques, including being slapped, slammed against a wall, forced to maintain stress positions and deprived of sleep. At some point, it isn't clear when exactly, Ghul told interrogators that the Kuwaiti was bin Laden's courier and frequently traveled with al Qaeda's leader.

It is quite possible, however, that Ghul gave this information up to his interrogators before he was subjected to coercive interrogations. The Senate Select Committee on Intelligence has undertaken a multiyear study of the CIA interrogation program and has generated a 6,000-page report that will likely be released in some form later this year. Once that report is made public it will surely definitively answer whether Ghul gave up this key information about the Kuwaiti while he was being subjected to coercive measures, or not.

For the moment, we will have to content ourselves with a press release from the Senate Select Committee on Intelligence dated April 27 that says, "The CIA detainee who provided the most significant information about the courier provided the information prior to being subjected to coercive interrogation techniques." This detainee appears to be Ghul.

Mohammed's replacement as the No. 3 in al Qaeda, Abu Faraj al-Libi, held that position for only a couple of years before he was arrested in Pakistan on May 2, 2005, in the city of Mardan, 100 miles from Abbottabad, where bin Laden himself would soon arrive to live for the next six years.

A month after his arrest, Libi was handed over to the CIA. Coercive interrogation techniques (though not waterboarding) were used on him. Libi also told his interrogators that the Kuwaiti wasn't an important player in al Qaeda and that it was in fact "Maulawi Abd al-Khaliq Jan" who was bin Laden's courier. Counterterrorism officials later concluded that Maulawi Abd al-Khaliq Jan was a made-up name.

So, did coercive interrogations lead to bin Laden? Such techniques were used on Qahtani, the 20th hijacker, and on Ghul, the Pakistani al Qaeda courier who was captured in Iraq.

Certainly both Qahtani and Ghul gave interrogators information that led the CIA to focus on the Kuwaiti as a possible avenue to finding bin Laden, which to defenders of these interrogation techniques would seem to prove that they were effective. That said, it is quite possible, however, that Ghul gave up the information about the Kuwaiti before he was coercively interrogated.

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Critics of the coercive interrogation techniques can point out that harsh methods were also used by the CIA to get Mohammed and Libi to talk, and both those men gave their interrogators disinformation about the Kuwaiti.