In March 2004 US Citizen Brandon Mayfield was identified as the primary suspect responsible for the Madrid Bombing by the FB, based on Fingerprint evidence. In April the Spanish National Police stated, in a written report that the finger print of Brandon was not a match. The following month, 6th May 2004, the FBI arrested Brandon Mayfield, 13 days later the Spanish police arrest the correct person, but the FBI did not fully release Brandon for five more days.
The detention was based on a single, imperfect finger print. The FBI had not see the original print, despite being given the opportunity by the Spanish police. Brandon was released on 21st May 2004, two days after the Spanish police had identified the correct suspect, Ouhane Daoud and 1 month after they stated Brandon’s fingerprint did not match
On the 13th March 2004 when the FBI first searched their database “AFIS” – Automatic Fingerprint Identification Search”, the result was negative, and they asked for a new, better quality image, which they received on the following day, on 14th March.
On 15th March 2004, 20 “matches” were found during the search – 20 were found as the search was programmed to limit show only 20 – i.e it could/would have many more, if it had not been limited to 20 people.
Brandon Mayfield was ranked number 4 on the search. Details of the 20 people identified in the search were extracted and background checks made. Brandon Mayfield has the following Bio:
American citizen born in Oregon and reared in Kansas. He lives with his wife and three children in Aloha, Oregon, a suburb of Portland. Mayfield was 38 years old, a former Army officer with an honorable discharge, and a practicing Oregon lawyer. However his faith is listed as Muslim.
The persons ranked number 1 to 3 were not arrested.
On April 13, 2004, the Spanish National Police provided a written report to the FBI concluding that Mayfield’s fingerprints did no match the scene of crime.
The FBI continued to investigate Brandon Mayfield, including bugging his house, etc, then on 6th May 2004 Bradon was eventually arrested, he was put in solitary confinement, his family was told the evidence was “100%” and leaks to the press about the guilt of Brandon were made.
On 19th May 2004 the Spanish Police correctly identified who the fingerprint belonged to, an Algerian called -Ouhane Daoud. However the FBI continued to detain Brandon until the 21st – when the story made the news. Even then Brandon was still placed under home arrest until 24th May, when the FBI finally released him.
This case, along with the case of David Asbury, shows how large amounts of data, and fingerprints in particular, can and are misused.