The story of Dr. Hawley Crippen seems like it was written for the movies—and it has in fact inspired more than three dozen books and films.

An American homeopathic doctor living in London throws a party, after which his showgirl wife goes missing. Scotland Yard starts sniffing around after the doctor moves his mistress into the house. The couple flees across the Atlantic on a steamship. Meanwhile, detectives discover partial human remains under a brick floor of Crippen’s basement. Upon arriving in port in Canada, the fugitive is arrested and hauled back to London, where after a trial that captivates the English-speaking world, he’s hanged for poisoning his wife, chopping her up, and burying parts of her in the cellar. 

 

An incredible enough story already, to be sure, but thanks to the modern tools of biotechnology, this nearly 100-year old case has developed a plot twist worthy of Hollywood. Researchers in Michigan using the latest forensic DNA analysis to examine tissue preserved from the crime scene have come to a startling conclusion: The remains aren’t those of Crippen’s wife Cora.

 

“Dr. Crippen was arrested and convicted of the wrong crime,” said David Foran, a forensic biologist and director of Michigan State University’s forensic science program who led the DNA testing. “But I’m not saying he’s an innocent man. There were human remains found, so there was something going on.”

 

That something has intrigued forensic toxicologist John Harris Trestrail III for nearly 40 years. It was Trestrail who rounded up the pro bono team of sleuths that included Foran and genealogist Beth Wills. Together they used mitochondrial DNA—a unique type of DNA that remains more stable in aged tissue than nuclear DNA, which is used in conventional DNA tests—to take another look at the evidence. Back in 1910, a forensic pathologist had persuaded a London jury that the remains were Cora’s by stating the tissue from the scene contained an abdominal scar consistent with her medical history.

 

What has for many years troubled Trestrail, managing director of the regional poison center in Grand Rapids, Michigan, is that Crippen’s case is the only one he’s heard of in which a poisoner dismembered the victim. “A poisoner tries to eliminate obstacles between him or herself and a goal and walk away,” said Trestrail. “When you start cutting up a victim, you are not going to get a natural death certificate, are you?”

 

In March 2007, the Michigan group received a slide from the Royal London Hospital Archives and Museum containing the same tissue that helped send Crippen to the gallows. The forensic biologist Foran, at his lab at Michigan State University, began a painstaking process of isolating the mitochondrial DNA. Challenges abounded. Pine sap used to glue the slide at the time required Foran to essentially break the slide to free the tissue. Next, Foran had to find a way to get viable samples of the DNA as the tissue had been fixed in formaldehyde, which makes it difficult to isolate the genetic material.

 

The focus was on mitochondrial DNA, which is passed unaltered from a mother to her children, unlike nuclear DNA, where the genetic information is diluted every generation. After seven years of research, Wills located Cora’s half grandnieces; their cheeks were swabbed and tested and compared to the DNA in the slide. There was no match. “Just before he was hanged, Crippen wrote a letter saying, ‘I am innocent and some day evidence will be found to prove it,’” Trestrail said. He and Foran said that day may have come, at least as far as the murder of Cora is concerned, though some skeptics, Foran acknowledges, aren’t convinced by the DNA evidence. “The slide is available if other people want to verify our testing,” he said. “I don’t have any agenda.”

 

Today, nuclear DNA is used in most forensics cases as it’s the basis for many DNA databases including the U.S.’ CODIS database. But mitochondrial DNA testing is likely to become more prevalent, especially in missing persons cases involving mass graves found in places like the Balkans and Latin America, said forensics DNA expert Chris Asplen, a lawyer and lobbyist for Gordon Thomas Honeywell in Washington, D.C. “You would want to use mitochondrial DNA in cases where you are looking at evidence that is particularly degraded and nuclear DNA is not an option,” he said.

 

Of course if mitochondrial DNA proves Crippen’s innocence in the killing of his wife, it actually raises more questions than it answers. Among them, whose remains were those in the cellar, and, whatever happened to Cora Crippen? Her husband told authorities she had run off with another man. Foran said he’s now working on determining whether the remains belonged to a man or woman. More daunting will be to figure out who else might have gone missing at the time. As the crime occurred in London nearly a century ago, seems likely there’ll be elements of this case that always remain a mystery—just as a good screenwriter would have it.