New DNA Analysis On Old Blood Pegs Aaron Kosminski As Jack the Ripper

It surely won't be the last theory offered, but a century and a quarter after the notorious crimes of Jack the Ripper, an "armchair detective" has employed DNA analysis on the blood-soaked shawl of one of the Ripper's victims, and has declared it in a new book an unambiguous match with Jewish immigrant Aaron Kosminski, long considered a suspect. Kosminski died in 1919 in an insane asylum. The landmark discovery was made after businessman Russell Edwards, 48, bought the shawl at auction and enlisted the help of Dr Jari Louhelainen, a world-renowned expert in analysing genetic evidence from historical crime scenes. Using cutting-edge techniques, Dr Louhelainen was able to extract 126-year-old DNA from the material and compare it to DNA from descendants of [Ripper victim Catherine] Eddowes and the suspect, with both proving a perfect match. (Also at The Independent.) It's not the first time DNA evidence has been used to try to pin down the identity of Jack the Ripper, but the claimed results in this case are far less ambiguous than another purported mitochondrial DNA connection promoted by crime novelist Patricia Cornwell in favor of artist Walter Sickert as the killer in a 2002 book. Update: 09/07 16:03 GMT by T : Corrected Sickert's first name, originally misstated as "William."

Comments

forensic 'science'

[fermion]

This is where I think we get in trouble with forensic science. Certain things, like finger prints and DNA, can exonerate a suspect but we have seen enough analysis around here to know that it is a fallacy to think that these things prove guilt. it only proves guilt if we assume the probability of guilt is 100% initially. When comparing the sample to a database, random error can create a match under certain common circumstances.

So we can say that DNA evidence is part of a chain that can lead to guilt, and if we assume the known suspects represent the total population of possible suspects, then if the DNA exonerates all other suspects, then there is a case to be made for guilt, but that is a lot of caveats. As we have seen in many cases, obvious suspects are ignored because the authorities jump to quick conclusions. As said, DNA is good for exonerating people, not convicts them.