KNOXVILLE, Tenn. - Thanks to new testing available at the Smithsonian Institution in Washington, the Knox County Sheriff's Office authorities hope they are one step closer to identifying two homicide victims from more than two decades ago.
The teeth of an unidentified victim from 1982 and a 1987 Jane Doe have been sent to a Smithsonian laboratory for what is known as stable isotopes analysis, with the hope of determining the geographic region in which they grew up.
When sheriff's forensic officer Amy Dobbs was put in charge of department cold cases nearly two years ago, those investigations were both at a standstill. After reading about how stable isotope testing can eliminate up to 80 or 90 percent of the world when finding where somebody spent their childhood years, Dobbs decided to make her best sales pitch to the Smithsonian, one of only three such testing sites in the country.
Her first contact with them was in late December, with the expectation that she wouldn't hear back any time soon. But it was just days later, she said, that they responded with a decision to extend their services and aid in the investigation.
"I'm really excited that they have picked up our two cases to help us," Dobbs said. "It may or may not lead to identifications of both of them, but just the fact that it's a new lead that we have to go down is pretty amazing to me."
She wasted no time sending the necessary teeth to Dr. Christine France, who manages the Smithsonian's Stable Isotope Mass Spectrometry Laboratory.
Dobbs is hoping to have an answer by the end of this month, assuming there are no glitches in the process.
"We are looking at the chemical components in the teeth that are directly transferred from ingested water and attempting to match the teeth to an area with drinking water of a similar chemical signature," France explained. "The accuracy will be limited to a general area, such as the (U.S.) Southeast or Canadian Rocky Mountain region."
Admittedly, France realizes those areas are quite large to conduct a search. However, she said that was just one element of the sheriff's investigation.
Once analysis is complete, Dobbs plans to distribute facial regression pictures created by a laboratory at Louisiana State University in Baton Rouge to the media and law enforcement in the pinpointed areas of origin. Her hope is that someone will recognize the images as resembling a childhood friend or possibly even a family member, in which case a DNA test would be performed to make a positive identification.
"You still have victims. You still have a victim's family, so somebody out there has to be missing them. They don't forget," she said. "It doesn't get any easier for them and they continue to search."
The technology used in stable isotope testing is fairly new to the United States, but France has seen it yield successful results over the last 10 years in other labs around the world. Her experience with it has been strictly for archaeological research to this point, but said she's looking forward to the opportunity to apply it to a modern case and help people in a practical way.
"I have applied this technique to hundreds of specimens with a fairly good success rate," France said. "Modern humans tend to have a more global diet, which does interfere somewhat with the chemical signatures of a local region. But my research and the work of others suggests the technique is still useful for identifying general area of origin in people today."
As an advocate for the National Missing and Unidentified Persons System, Dobbs realizes the potential this could have on future cases.
"Who knows? If it does work it's going to open the doors for other long-term unidentified cases," she said. "These people were born with a name and we ought to be able to have the dignity to bury them with a name."