Coleman, a 31-year FBI veteran, joined other former law enforcement colleagues in expressing skepticism about Abu Zubaida's importance. Abu Zubaida, he said in an interview, was a "safehouse keeper" with mental problems who claimed to know more about al-Qaeda and its inner workings than he really did.

Looking at other evidence, including a serious head injury that Abu Zubaida had suffered years earlier, Coleman and others at the FBI believed that he had severe mental problems that called his credibility into question. "They all knew he was crazy, and they knew he was always on the damn phone," Coleman said, referring to al-Qaeda operatives. "You think they're going to tell him anything?"

But, Coleman and other law enforcement officials said, CIA officials concluded to the contrary that Abu Zubaida was a major player, and they saw any lack of information as evidence that he was resisting interrogation. Much of the threat information provided by Abu Zubaida, Coleman said, "was crap."