In Mayfield case, fingers are pointing

"When the FBI went through Brandon Mayfield's possessions to investigate his connection with the Madrid train bombings, agents seized what they called "miscellaneous Spanish documents."
As The New York Times reported, Mayfield's family later identified the documents as his children's Spanish homework. . . .
But by April 13, according to the Times, the Spanish told the FBI that the match was "conclusively negative." In a meeting with the FBI in Spain April 21, Spanish officials insisted there was no match, while FBI agents insisted there was -- but never asked to see the actual bag.
By then, the FBI had found that Mayfield was a Muslim convert, that he was often seen driving to the Bilal Mosque, and that he had represented, in a child custody suit, one of the Portland Seven convicted terrorists.
It's understandable that these discoveries -- or the fingerprint match itself -- would set off alarms. The question is whether the discoveries about Mayfield began to overwhelm the weaknesses the Spanish kept noting in the fingerprint match.
The claim of probable cause, says federal public defender Steven Wax, was based on "some sort of guilt by association with people who may have had contacts with other people the government had concerns about."
And then, Mayfield's possession of "miscellaneous Spanish documents."