Tracing the truth

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LINDSAY MAST, HOST: Today is Thursday, July 31st.

Thank you for turning to WORLD Radio to help start your day.

Good morning. I’m Lindsay Mast.

PAUL BUTLER, HOST: And I’m Paul Butler.

Coming next on The World and Everything in It: solving cold cases.

According to the FBI over the past 30 years in the U-S, more than 100,000 murder cases have gone cold. Other estimates put the total number of unsolved homicides at around 270,000.

MAST: An estimated 42 percent of murders in America go unsolved. That leaves loved ones looking for answers and killers on the loose.

But a new technology could change that. And, a word of caution: this story deals with crimes and details that may not be suitable for younger listeners.

WORLD correspondent Maria Baer reports.

MARIA BAER: Thirty miles outside of Columbus, Ohio, sits the state’s Bureau of Criminal Investigations, or BCI.

DREYER: So what I’m going to do, I just need you to stay here…

On the second floor of this imposing brick building, behind a series of ID-required security doors, is the state’s DNA lab.

Hallie Dreyer is the lab’s director. She points behind a wall of glass windows, where lab technicians in white coats are poring over a piece of clothing. It’s a pair of women’s underwear, and it looks stark and wrong lying on the sterile table. Dreyer says they’re collecting DNA from an assault.

DREYER: She’s going to open those up, she’ll document the condition. She’ll kind of open them, and then we’ll do some screening tests…

Maybe the DNA from this crime scene will hit in CODIS — that’s the Combined DNA Index System. This is where the FBI maintains DNA profiles collected from crime scenes and suspects across the country for cross-referencing.

Or maybe this DNA won’t match any profiles in that database.

DREYER: The cases that don’t benefit from that, meaning we don’t get a hit, link, or an answer, we’re still investigating, that’s where we consider that next step, which is investigative genealogy.

Investigative genealogy involves comparing DNA collected at a crime scene, or from unidentified human remains, with the databases of consumer genealogy sites.

These at-home DNA testing products hit the market in the mid-2000s. 23andMe was the pioneer, founded in 2006. This and other companies like it provide consumers with a saliva-collection kit, which they can send away for testing. In a few weeks, customers receive a digital readout of several genetic markers. Hobbyists use the information to learn their ethnic background or even find relatives.

Increasingly, police are using it to find killers.

YOUTUBE: It’s a story that captured the attention of central Ohio. Eight-year-old Kelly Ann Prosser was kidnapped, raped, and killed, and for nearly 40 years, no arrest in the case. Thanks to a DNA match, now the police say the case is solved.

In 1982, Kelly Ann Prosser was abducted on her walk home from elementary school. Columbus cold case investigators said they never stopped working her case. But it was investigative genealogy that gave them their break.

YOUTUBE: Columbus police say a family tree was built through a partnership with Advance DNA that led them to a name they could use to go back through the case file.

Detectives had collected DNA at the scene of Kelly Ann’s murder, but it hadn’t matched in CODIS. With the help of a genealogy company, they instead used it to follow the killer’s family tree back to his doorstep.

There is fine print inside every user agreement for consumer-based DNA testing products. Some include a waiver that grants law enforcement access to their databases. 23andMe does not; but two others, GEDmatch and Family Tree DNA, do.

DREYER: Those are the law enforcement friendly ones that you can search.

That means some consumers who don’t read all the terms and conditions might not realize their DNA profile is freely accessible to police.

At least four states—Texas, Utah, Maryland and Montana—have passed legislation limiting law enforcement’s ability to search these databases. In some states, police must obtain a warrant.

Ohio investigators say investigative genealogy is a last resort when a case has hit a dead end. It’s expensive and time-consuming.

DREYER: You may get a hit in one of these databases where it’s a very high match. Meaning this is probably a parent or a child, those are great when you get them, it’s easy to build a tree. But more often than not, you’re getting those lower, where it’s like, ok it’s a second cousin once removed, and you’re trying to build back to a common ancestor. That can take months to years just depending on the types of tree that you’re building.

Sometimes, in the process of building a family tree, investigators need to reach out to a suspect’s family members to request a voluntary DNA sample. Special Agent Roger Davis leads Ohio’s cold case unit. He says most people are willing to comply—even when it gets personal.

DAVIS: I do know of a case where the person we talked to and got the sample, it was their brother who was actually the person who did it. But he even said, he goes, I’m a little conflicted, but if this is proving what he did to that person. I will help you in any way possible.

Dreyer says while the technology is becoming more sophisticated, it’s still not a perfect science. One thing DNA can’t tell investigators: whether the culprit was a twin.

DREYER: That’s why we never say in our reports or when we’re making our conclusions that it is his DNA and only his DNA. We say the DNA profile is consistent with him, and then we calculate a statistic that indicates the rarity of that. Because yes it may be rarer than one in a trillion, but what if he has an identical twin…

Incredibly, the twin problem has come up before.

DREYER: We’ve had it where the twin will blame his brother in the interview. No, that wasn’t me, it was my brother. Then it comes down to the investigative work, the timeline of where each of them where, what are the cell phone records…

Inside Ohio’s BCI lab, a machine that looks like a very high-tech microwave is filled with dozens of pipets.

AUDIO: [Beeps, machine whirring]

A robotic arm swivels over the pipets. Dreyer says this is called DNA extraction.

DREYER: Think of it as a tiny washing machine, you add detergent, break open the cells, extract the DNA, wash away all the other junk.

After a few more steps, technicians will create a report detailing whatever genetic information they could extract.

Special Agent Davis says he believes law enforcement will increasingly use investigative genealogy as they get used to the technology. The innovation reminds him of the way cell phone tracing technology revolutionized police work in the nineties.

Despite the privacy concerns, Davis believes civilians want to see violent crimes solved - to know that there is “nothing hidden that will not be made manifest.”

Dreyer agrees.

DREYER: There’s been huge changes with it. How we would look at a case 15, 20 years ago - how we would look at a case five years ago, has evolved since then. I’ve been in the field 15 years now, I continue to see the technology will evolve. It will grow.

Reporting for WORLD, I’m Maria Baer in London, Ohio.

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