The Fingerprint That Lied in Madrid
After the 2004 Madrid train bombings, the FBI matched a partial fingerprint to an Oregon lawyer named Brandon Mayfield and jailed him — but Spanish investigators insisted the print belonged to someone else. This is the story of how three certified examiners agreed on a match that was flat wrong, and what it revealed about the myth of infallible forensics.
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The FBI wrongly identified an Oregon lawyer as a terrorist based on a single partial fingerprint.
Digital databases can produce twenty potential candidates who share similar fingerprint characteristics by chance.
Confirmation bias led three FBI examiners to ignore the fact that the suspect lacked a passport.
A Department of Justice investigation revealed that fingerprint analysis is an interpretive discipline, not a mechanical science.
A black box study found a zero point one percent false positive rate among fingerprint examiners.
The FBI implemented blind verification to prevent peer reviewers from being influenced by previous conclusions.
- 01Intro1 min
- 02The Match in the Rubble2 min
- 03The Spanish Dissent2 min
- 04The Anatomy of an Error2 min
- 05The Black Box of Forensics2 min
- 06Outro1 min
- Brandon Mayfield - Wikipedia
- 2.3 Context and potential error in fingerprint analysis | OpenLearn
- Report: FBI Problems Led to Wrongful Terror Arrest
- Statement of Tasia Scolinos, Director of Public Affairs, on The United States’ Settlement with Brandon Mayfield
- CHAFTER
- Beyond a Reasonable Doubt? Fingerprint Evidence's Troubling Flaws
- F.B.I. Is Cleared of Misconduct in Jailing of Oregon Man
- The History and Legacy of the Latent Fingerprint Black Box Study
- [PDF] Draft guidance: Cognitive bias effects relevant to forensic science ...
- Forensic Science Regulator Guidance
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