You read the article right? Al Jazeera implies they didn't follow their own procedures, not the FBI. The FBI constructed a theory, and sought to validate or invalidate it.
You can read the actual OIG Report [1] it is online, but the interesting bit is here, in Chapter 7 (page 269):
"Based on our investigation, we concluded that the three FBI examiners who misidentified Mayfield's print were confused by the fact that the fingerprint on the Madrid bag contained as many as 10 points that corresponded to details in Mayfield's known finterprints in relative location, orientation, and intervening ridge count. This degree of similarity is extraordinarily rare and confused three FBI fingerprint examiners as well as a fourth, outside, court appointed examiner."
I don't know how much you know about fingerprint forensics, I just know what I read, but a 10 point match is considered pretty strong from what I've read. And as I mentioned earlier, its a statistical thing not an exact thing.
Al Jazeera isn't implying it they are stating facts directly from the FBI OIG's own report. Check out Chapter 4 page 128 it says that one of the examiners didn't follow proper procedure, there was intense pressure because of the magnitude of the case and the two others who reviewed the initial finding had knowledge of the initial conclusion so there was pressure on them to agree with it.
You can read the actual OIG Report [1] it is online, but the interesting bit is here, in Chapter 7 (page 269):
"Based on our investigation, we concluded that the three FBI examiners who misidentified Mayfield's print were confused by the fact that the fingerprint on the Madrid bag contained as many as 10 points that corresponded to details in Mayfield's known finterprints in relative location, orientation, and intervening ridge count. This degree of similarity is extraordinarily rare and confused three FBI fingerprint examiners as well as a fourth, outside, court appointed examiner."
I don't know how much you know about fingerprint forensics, I just know what I read, but a 10 point match is considered pretty strong from what I've read. And as I mentioned earlier, its a statistical thing not an exact thing.
[1] http://www.justice.gov/oig/special/s0601/PDF_list.htm