Forensic isotope analysis points cold case investigation north to Canada

There is an old saying that you are what you eat, and it turns out it might hold the clue to unraveling the mysterious identity of a woman found dead nearly two decades ago in Wisconsin, who may have been raised in Canada.

'You are what you eat': Chemical traces in bones, hair may hold the key to cracking decades-old case

Investigators used facial reconstruction software to create this image, left, of an unidentified woman whose body was found in Racine, Wisconsin, in July 1999. She was wearing the the grey shirt with red flowers, pictured right, at the time of her death. (National Center for Missing & Exploited Children )

The old saying "You are what you eat" might hold the clue to unraveling the mysterious identity of a woman found dead nearly two decades ago in Wisconsin, who may have been raised in Canada.

The young woman's body was discovered on the edge of a cornfield near Racine, Wis., by a man walking his dog on July 21, 1999, according to Caroline Schweitzer, supervisor of forensic services with the National Center for Missing and Exploited Children in Virginia.

"She had only been there less than 24 hours," Schweitzer said. "She was facially recognizable — if somebody saw her picture they would know who she was."

The woman had many distinguishing features, including curly red-brown hair, ears pierced twice, and a Western shirt embroidered with red flowers she was wearing.

But despite that, nobody came forward to identify her.

And from the beginning there were deeply troubling signs about her origins: Her teeth were in very poor condition and her slight body was obviously malnourished.

But even more alarming was the extensive physical abuse that appeared to have taken place over several weeks before her death.

"When she was discovered, she was obviously beaten and horrifically tortured prior to her death," said lead investigator Tracy Hintz, with the Racine County Sheriff's Office.

And that led investigators to the conclusion that she might have been held against her will for some time before she was beaten and left for dead.

Stable isotope analysis points northward

Over the years, Hintz and others searched multiple U.S. missing-persons databases, and used facial reconstruction software to create photographs, posters and Facebook posts.

But they were never able to crack the case of the woman known only as Jane Doe 1999.

Three years ago, they even exhumed her remains for DNA testing but still came up empty-handed.

"We have her DNA, but if we don't know who she is, we are kind of stuck," said Hintz.

So the decision was made to send fragments of her bone and hair to researchers at the Smithsonian Institution in Washington, D.C., for a process called stable isotope analysis.

Anthropologists have used stable isotope analysis for years to track the migrations of ancient humans. Criminal investigators also use it to trace the origins of explosives and drugs.

And increasingly in cases like this one, it is used to try to determine the origin of unidentified individuals.  

No perfect matches

But unlike DNA analysis, which can provide a near perfect match with an individual, stable isotope analysis cannot identify people.

What it can reveal instead are subtle clues about diet, geography and movements of a person in the months and years before their death.

It does this by using a device called a mass spectrometer, which measures variations in the molecular level of elements such as oxygen, nitrogen, carbon and hydrogen that are absorbed into our bones, teeth and hair from the food and water we consume.

Mass spectrometers measure the particular ionic signature of chemical compounds. They are used in many different applications. (Nadina Wiórkiewicz/Wikipedia Commons)

"Basically, you are what you eat," says Hintz. "Those stable isotopes stay in different parts of your body as you grow." And, she explains, the levels of these various isotopes will vary depending on where you live in the world.

In the case of Jane Doe 1999, those clues led investigators to expand their search area far wider than before.

What they learned was that the young woman, who they believed to be between the ages of 15 and 30, may have been from, or spent several years in, somewhere within a broad stretch of southern Canada between British Columbia and Newfoundland, or possibly even parts of the western U.S. such as Alaska or Montana.

Tips are pouring in

While the new clues expanded the search area to a huge swath of new territory, they also helped investigators refocus on new sources for clues.

Hintz had hoped to receive tips from people north of the border  — and they started pouring in after this information was released, she said.

"Yes, I have been very busy," she said Tuesday morning. "[The tips] are all appreciated. They can lead to something or lead to ruling something out."

Hintz says while it will take a long time to prioritize the new tips, and run down every clue, the cold case is one she is devoted to cracking one day.

"If it is a sleepless night at home, I will pull out this case and work on it from there," she said.

"This is why I came back to the detective bureau. I specifically asked for this case because she deserves more than this, no matter who she was or where she lived."

Ultimately Hintz has two goals. The first is identifying the young woman found battered and left for dead on the side of the road nearly two decades ago, and give her back a name.

"The other is to bring those who are responsible for this to justice," Hintz said.

Anyone with a tip is asked to call 1-800-843-5678 or contact Hintz directly at (262) 636-3190.