So, last year, I wrote an article entitled "Fingerprint Evidence Not Always Accurate", and the article discussed a few issues regarding the scientific reliability of fingerprint evidence.
Basically, fingerprint comparisons are a statistical science due to the probabilistic nature of such comparisons (isn't most science, at its core, probabilistic? The behavior of matter, on the quantum level, is probabilistic). For example, when a fingerprint examiner claims that two prints "match", the general public just assumes that the two prints are identical. But this is an incorrect statement. Actually, the expert fingerprint examiner has merely "matched" a few unique points on the two prints, and from those matches he/she just presumes that the rest of the fingerprint must match up as well. That's hardly an exact match, or an exact science.
When a fingerprint expert claims that the defendant's fingerprint matches a print at the crime scene, the expert has merely identified patterns and placements of features like loops and ridges-- leading to the claim that no two prints on Earth would have 4 loops and 5 ridges in said locations. Is that so? Well, the odd thing is, no large scale scientific study has ever been done to create any sort of foundation to support such statistical claims. Indeed, it may be that several hundred, or thousand, or whatever, people may have those loops and ridges in those locations on their finger. We just don't know, no one has bothered to study it. But I can assure you, every prosecutor in Florida is ready to tell a jury the "fact" that the fingerprint at a crime scene IS from the defendant's finger. That the fingerprint IS a MATCH. Wow! No two prints are the same, right?
So, last year, I wrote an article entitled "Fingerprint Evidence Not Always Accurate", and the article discussed a few issues regarding the scientific reliability of fingerprint evidence.
Basically, fingerprint comparisons are a statistical science due to the probabilistic nature of such comparisons (isn't most science, at its core, probabilistic? The behavior of matter, on the quantum level, is probabilistic). For example, when a fingerprint examiner claims that two prints "match", the general public just assumes that the two prints are identical. But this is an incorrect statement. Actually, the expert fingerprint examiner has merely "matched" a few unique points on the two prints, and from those matches he/she just presumes that the rest of the fingerprint must match up as well. That's hardly an exact match, or an exact science.
When a fingerprint expert claims that the defendant's fingerprint matches a print at the crime scene, the expert has merely identified patterns and placements of features like loops and ridges-- leading to the claim that no two prints on Earth would have 4 loops and 5 ridges in said locations. Is that so? Well, the odd thing is, no large scale scientific study has ever been done to create any sort of foundation to support such statistical claims. Indeed, it may be that several hundred, or thousand, or whatever, people may have those loops and ridges in those locations on their finger. We just don't know, no one has bothered to study it. But I can assure you, every prosecutor in Florida is ready to tell a jury the "fact" that the fingerprint at a crime scene IS from the defendant's finger. That the fingerprint IS a MATCH. Wow! No two prints are the same, right?