While everyone else is holding up FBI whistleblower Coleen Rowley as a hero for exposing the Bureau's incompetent failure to follow through in investigating Zacarias Moussaoui, law professor Jonathan Turley holds a different point of view:
What is astonishing is how little of her memo actually has been read or quoted beyond its most sensational suggestions, like the notion that Rowley and her colleagues might have been able to prevent one or more of the Sept. 11 attacks. Rowley's criticism of the FBI largely turns on disagreement over the meaning of probable cause. Rowley insists that there was probable cause to secure a search warrant for Moussaoui's computer and personal effects. The FBI headquarters disagreed, and it was right.Turley argues that the 9/11 attacks provided the probable cause which was lacking before. Of course, unless Turley knows far more about the French information than he's saying, I don't see how he can possibly come to a conclusion about the existence of probable cause. Moreover, Turley ignores the complaint by Rowley that the FBI didn't even try to get a warrant.On Aug. 15, 2001, Moussaoui was arrested by the Immigration and Nationalization Service on a charge of overstaying his visa. At that time, the Minnesota office only had an "overstay" prisoner and a suspicion from an agent that he might be a terrorist because of his religious beliefs and flight training. If this hunch amounted to probable cause, it is hard to imagine what would not satisfy such a standard.
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Rowley also places importance on a French report that "confirmed [Moussaoui's] radical fundamentalist Islamic" affiliations. This report was extremely vague and discounted by the FBI and other intelligence and foreign agencies.
Note: the memo in question, written by Rowley, is here.