In 1888, a serial killer dubbed Jack the Ripper brutally murdered at least five prostitutes in London's East End. In a new book, an "armchair detective" from London named Russell Edwards says he has "definitely, categorically, and absolutely" discovered the identity of the killer: Polish immigrant Aaron Kosminski. Kosminski, a barber in Whitechapel who was 23 at the time, was one of the top six suspects but never arrested; he died in an insane asylum at age 53.
So, how did Edwards prove his case? DNA. In 2007, Edwards bought a blood-soaked shawl said to belong to Catherine Eddowes, one of Jack the Ripper's victims, apparently taken from the crime scene by a police sergeant, Amos Simpson, who wanted it for his wife. Edwards roped in a molecular biologist named Jari Louhelainen, who used DNA techniques to identify both blood from Eddowes and genetic material that matched with Kosminski's descendants.
"I've got the only piece of forensic evidence in the whole history of the case," Edwards says. There are doubters, of course. Some point out that the 126-year-old scarf, while apparently never washed, has been handled by lots of people, tainting the DNA. And there's no independent verification of Louhelainen's findings, or even that the shawl was really found next to Eddowes' body.
"I am of the camp that believes extraordinary claims require extraordinarily clean and robust evidence," says Susannah L. Bodman at The Oregonian. "A shawl with no provenance record and an association based on a family claim is not what I call extraordinarily robust."