The New York Times explores how the FBI could get the wrong guy and be so sure he was the right one: The F.B.I. quickly and confidently found a match to a Portland-area lawyer, setting in motion a chain of events that led the authorities in the United States to link the wrong man to those fingerprints, tie him to Islamic terrorists, arrest him on a material-witness warrant, jail him for 14 days, drop the entire case on Monday and then face withering questions about how the investigation could have gone so wrong. Court records unsealed Tuesday showed that the Spanish authorities had raised questions about the F.B.I.'s fingerprint match to the lawyer, Brandon Mayfield, 37, weeks before his May 6 arrest. Yet F.B.I. officials were so confident of a match they described as "100 percent," the court papers show, that they never bothered to look at the original print while they were in Madrid on April 21, meeting with Spanish investigators.