Everyone knows that human fingerprints are unique. After all, even identical twins don’t share the exact same pattern of whorls and furrows and, in fact, no two sets of human fingerprints have ever been found to be identical.
But it may surprise you to learn that the idea that human fingerprints are unique is an assumption, not a well-studied idea. Fingerprinting had become a staple of law enforcement techniques long before that question was even broached, but it still has never been actually proven. This lack of a fundamental scientific basis for the supposed uniqueness of fingerprints — and the inability for apparent experts to reliably match them or even agree on what’s required for a match — has seen some federal courts reject fingerprints entirely as evidence.
