March 11, 2004 -- 10 bombs explode on four commuter planes in Madrid. 191 people die in the attacks. 1,500 more suffer injuries.

AP photo

Portland lawyer Brandon Mayfield holds up a book titled "The Meanining of the Holy Quaran" after his release from jail.

May 6, 2004 - Attorney Brandon Mayfield is arrested at his office on a material witness warrant. Spanish investigators claim mayfield's fingerprints were found on bags containing the same type of bomb detonators used in the attack.

May 11, 2004 - Mayfield's family tells Newschannel 8 that he testified before a grand jury.

May 21, 2004 - Mayfield released from custody after Spanish authorities determine fingerprints belong to someone else.

September 2004 - U.S. Justice department launches investigation into Mayfield's arrest, specifically looking into the use of the "Patriot act" in his arrest.

October 4, 2004 -- Mayfield sues federal government, challenging the constitutionality of parts of the Patriot Act and alleging violation of his civil liberties.

November 2004 - Report on the Mayfield case is released. In it, finger print experts claim human error led to his arrest.