But haven’t they used DNA to identify Jack the Ripper?

When the Ripper murders happened in the fall of 1888, police had very little to use in the form of forensics. This was before fingerprints – and long before DNA – at a time when murder victims were rarely even photographed at the scene of the crime. It was also at a time when people thought that taking good, close-up photographs of people’s eyes would reveal the last thing they had ever seen. Forensics in 1888 definitely did not look like an episode of CSI.

But we’re in the 21st century now, and we do have access to a lot of forensic technological advances. DNA was first used in a criminal investigation in 1986, and since then advances mean that we could certainly test the Ripper’s DNA – right?

Well, so far two people have tried.

If you’ve only read one book about Jack the Ripper, chances are it’s Patricia Cornwell’s 2002 Portrait of a Killer: Jack the Ripper – Case Closed. Here she is on the back, examining a document carefully while wearing clean white gloves to apparently indicate she’s in an archive. Known for her fiction, especially her series about medical examiner Kay Scarpetta, Cornwell decided to use her personal wealth to investigate the Ripper crimes. Her research, which was updated first in a Kindle single and in a 2017 follow-up book, directed her toward accusing artist Walter Sickert as having been Jack the Ripper.

Although Cornwell did buy a number of Sickert’s paintings – and have to defend herself against accusations of wantonly destroying them in her search for evidence – her source of the Ripper’s DNA came from some of the Ripper letters. (We’ve talked about those before …) By swabbing the flap of the envelope and the stamp, Cornwell hoped to collect the Ripper’s DNA to compare it directly to Sickert’s.

There are a couple issues here, in spite of how cool she might look on the back cover of the second book in her Matrix-style coat. First, her methods assume that the Ripper himself licked the stamps and the envelopes. This means both that the letter wasn’t handed over to an employee who sold the stamp and did the honors, and that the Ripper actually wrote the letters. And second, because of the age of the letters, only mitochondrial DNA could be tested. At best, mDNA showed that Sickert could not be excluded from the tens (or possibly hundreds) of thousands of possible people who could have licked the envelope. Cornwell’s experts told her she had narrowed the Ripper down to about 1% of the Victorian British population, and in her book she translates this as indicating that yes, it was Sickert.

So mDNA from the likely hoax Ripper letters not excluding Sickert from the possible thousands to have licked it does not prove that Walter Sickert was Jack the Ripper. (Cornwell also has the difficulty of explaining how her chosen Ripper was meant to be in France at the time of the murders, on top of her theory that Sickert wrote most, if not all, of the Ripper letters himself. As an artist he was apparently amused by disguising his handwriting.)

The second example, most recently hitting headlines as the results were published in the Journal of Forensic Sciences, involves a shawl. This shawl was supposedly removed from Catherine Eddowes’ possessions after her murder and never officially recorded as having belonged to her. A police officer is meant to have taken it as a gift for his wife (since somehow it avoided being covered in blood) but then, mysteriously, the shawl passed from hand to hand and traveled through the decades … without ever having been washed.

In 2007, Russel Edwards bought the shawl at auction, believing the story of its provenance when other Ripper scholars present scoffed at the idea. Like Cornwell, he had DNA tests run, this time checking for matches to two people. (Again, note the CSI-style photographs.) Edwards concluded that the blood found on the shawl could indeed have come from Catherine Eddowes, and that the semen did not exclude his personal choice for Ripper, Polish barber Aaron Kosminski.

But we’re left with the same sorts of issues. Edwards’ expert, Jari Louhelainen, was also limited to testing for mDNA. His results were like the ones Cornwell was given: they did not exclude the people Edwards was looking for, but it’s hardly a conclusive test when it only narrows the pool down to some thousands (again, in a range that might be from tens to hundreds). The shawl itself, like the letters, is questioned, since there’s no trail that actually connects it to Catherine Eddowes and it has a lot of traits that mean it probably didn’t belong to her. (The dye was not water-fast, for example, making it an unlikely possession of a woman who frequently slept rough. On top of that, Eddowes’ boyfriend had just pawned his boots so they could eat, while she supposedly hung on to this elaborate shawl long enough to die wearing it.)

Edwards’ book came out in 2014 and I spent a week greeting people with “Yes, I know about the shawl.” The journal article came out in 2019 and I gave a talk on Jack the Ripper and the limitations of these DNA tests to hopefully cut down ont he number of people who asked me about it. These books certainly sound good, with all this talk about 21st century science and the greatest criminal mystery of all time, but, in spite of their expense and the photo opportunities, these tests are far from conclusive.

No, DNA evidence has not identified Jack the Ripper.