Does DNA analysis prove conclusively that a deranged Polish barber named Aaron Kosminski was behind the famous "Jack the Ripper" murders of the 19th century? The claim has stirred up a hue and cry among professional and amateur sleuths who have been following the case for decades — proving only that the evidence is far from conclusive.
"Literally, we see articles like this a couple of times a year, but this one has gone viral," said Stephen P. Ryder, executive editor of "Casebook: Jack the Ripper," an online database and forum for so-called "Ripperologists."
In a newly published book titled "Naming Jack the Ripper," amateur historian (and Ripper tour operator) Russell Edwards says he's certain that the DNA findings have solved a long-mysterious string of murders that terrorized the seamier streets of London starting in 1888. "Put the case to bed," he told ITV News. "We've done this."
But the chain of evidence would never hold up in a court: It's based on fresh analysis of DNA recovered from a century-old bloodstained scarf linked to one of Jack the Ripper's victims, Catherine Eddowes. Edwards' scientific collaborator, Jari Louhelainen of Liverpool John Moores University, has linked some of the DNA from the stains to the genetic signature of Eddowes' distant relatives. Another DNA signature, purportedly attributed to semen on the scarf, was linked to relatives of Kosminski.
Ripperologists have known about the scarf, as well as Kosminski's status as a suspect, for years. The new twist has to do with the DNA tests. "There's kind of a 'CSI Effect' going on," Ryder said. "People hear 'DNA,' and they think it's 100 percent solved."
It's not solved, as Ripperologists are only too happy to point out in the Casebook forum.
"I would dearly love to see a fully referenced, scientific, juried account of the testing and the associated processes," one commenter wrote. "It's intriguing, but as others have pointed out, there are so many issues even beyond the DNA. If anything, it's raising more questions, not generating answers."
The arguments over back-and-forth changes in the Wikipedia page for "Jack the Ripper" became so heated that the page has been protected from editing.
Debate over DNA
One of the reasons for the controversy has to do with the limitations of the DNA test that was used. Louhelainen could recover the genetic signature only from mitochondrial DNA, or mtDNA, rather than the nuclear DNA that serves as a unique identifier.
MtDNA is passed down from a mother to her children, and many people can share the same mtDNA signature. The signature linked to Kosminski, T1a1, is a relatively common subtype. Thus, the determination doesn't mean much unless the signature can be narrowed down to a rarer subtype, or unless additional evidence can be brought to bear (as was the case for identifying the remains of Russia's Czar Nicholas II and his family).
A larger question has to do with the scarf's history: It's been open to contamination for decades, and it's not even clear that it was really left behind by Eddowes (or her killer) after the 1888 murder. "In the community of so-called experts, it's not really considered evidence," Ryder said.
Another 'Case Closed' moment?
Then there's the fact that Kosminski doesn't match up all that well with descriptions of the killer by contemporary witnesses. He was just 23 years old and reportedly slight of build. In contrast, witnesses have described a heavier-built, somewhat older man as skulking around the scenes of the crimes.
Kosminski has long been on the list of usual Ripper suspects, thanks largely to references to a "Kosminski' in the writings of investigators, but many modern-day Ripperologists are doubtful he could have pulled off one of history's most infamous strings of serial killings.
"If it actually was Kosminski, this guy was a borderline raving lunatic," Ryder said. "This was not a criminal mastermind by any means."
Ryder said the latest claims were reminiscent of another "Case Closed" moment in the tale of Jack the Ripper — the time in 2002 when crime novelist Patricia Cornwell declared that Victorian-era painter Walter Sickert was the killer, based in part on mtDNA analysis of a licked stamp.
"Until I see anything more than what I've seen so far, it's like the Patricia Cornwell case," Ryder said.