On August 19th, 1975, three girls hitchhiked home from a gas station on Washington Street in Indianapolis. Kandice Smith was eleven. Sheri Rottler was twelve. Kathie Rottler, Sheri's older sister, was fourteen. A man in a car stopped and offered them a ride. They got in. He drove them out of the city, into Hancock County, sexually assaulted one of the girls, stabbed all three, and left them for dead in a cornfield near Greenfield. Somehow, all three survived. The attacker earned a nickname from investigators: 'The Slasher.' He was never identified. The case went cold for nearly fifty years — until a specialized unit at Indiana State Police did something that would have been science fiction in 1975.
The Unit That Didn't Exist Until Two Years Ago
Indiana State Police's forensic investigative genetic genealogy team — the FIGG unit — has only existed in its formalized structure for about two years. The results have been immediate. A 1975 homicide resulting in an arrest. A conviction in a decades-old infant death case. An armed robbery from 2000, finally resolved. Each case was stuck. Traditional methods exhausted. Genetic genealogy broke them open.
The unit's structure is deliberately hybrid. Four scientists and a genealogist handle the chemistry side — DNA extraction, database uploads, genetic analysis. A separate detective team works the ground investigation. Recently, part-time civilian investigators have been added to supplement the detective team. The workload demanded it. There are simply too many cold cases waiting.
How Genetic Genealogy Actually Works
Traditional DNA analysis compares crime scene samples against law enforcement databases like CODIS, the Combined DNA Index System. If the perpetrator isn't in the system, investigators get nothing. Genetic genealogy flips that limitation entirely.
Instead of matching to criminals, investigators upload DNA to public genealogy databases — sites like GEDmatch and FamilyTree.com — where ordinary people have submitted their own DNA for ancestry research. The crime scene DNA might not match anyone directly. But it can match distant relatives — second cousins, third cousins, people who share great-great-grandparents with the unknown suspect.
From there, specialized genealogists build family trees — sometimes hundreds of people deep — working backward through birth records, marriage certificates, census data, newspaper obituaries, military records. Anything that maps the bloodlines. Somewhere in that tree is the suspect. The technique burst into public awareness in 2018 with the Golden State Killer case, when Joseph DeAngelo was finally linked to decades of murders and assaults through his relatives' DNA on GEDmatch.
The Slasher Case: 48 Years to an Answer
For the three survivors from 1975, life went on. But they never forgot. Forty-three years passed. Then, in 2018, one of them picked up the phone and contacted Sergeant David Ellison at IMPD, a cold case investigator. They asked a simple question: was there anything that could be done?
Ellison took the case. But there was a significant problem. The original DNA evidence from 1975 needed to be reprocessed. After nearly five decades, would there be anything left to test? In 2021, the Indianapolis-Marion County Forensic Services Agency attempted the extraction. They succeeded. After forty-six years, they developed a full male DNA profile from the original evidence.
Now they had DNA. But the suspect still wasn't in any law enforcement database. In August 2023, IMPD sent the DNA profile to DNA Labs International — a private forensic laboratory in Deerfield Beach, Florida — for genetic genealogy analysis. The lab uploaded the profile to FamilyTree.com and GEDmatch. They found distant relatives. Then the genealogists went to work.
By late 2023, a name emerged: Thomas Edward Williams. When investigators ran Williams through law enforcement records, they found something unexpected. Thomas Edward Williams had died in November 1983 in a Texas prison. He'd been serving time in Galveston for an unrelated crime. He was never arrested for the 1975 attack. Never charged. Never even suspected — until genetic genealogy found him forty years after his death.
The Privacy Questions That Won't Go Away
This technique isn't without controversy. When someone submits DNA to 23andMe or Ancestry or FamilyTree.com, they're uploading their genetic code to find relatives. But some of those databases — particularly GEDmatch — allow law enforcement access under certain conditions. DNA uploaded for ancestry purposes can become a tool for criminal investigation.
Privacy advocates argue this was never the intended purpose. People who submitted DNA never consented to being part of a law enforcement database. They wanted to find cousins, not solve crimes. Supporters counter that violent criminals forfeit certain privacy expectations, and the technique doesn't target innocent people — it identifies perpetrators by working through family connections.
There's also the question of what you're actually sharing. You're not just sharing your own genetic information. You're potentially sharing information about every blood relative you have. That third cousin you've never met? Your DNA match could identify them in a criminal investigation — not because they committed a crime, but because you share genetic markers.
Cold Cases Are Falling
Kandice Smith, Sheri Rottler Trick, and Kathie Rottler were children when this happened. They're grandmothers now. They survived something that could have killed them, carried it for decades, and when the opportunity came to push the case forward, they picked up the phone. Thomas Edward Williams died in 1983 without ever facing justice. But his name is known now. The case is closed. The 'Slasher' isn't a ghost anymore.
For investigators with evidence that's sat dormant for decades — and for survivors who've waited half a lifetime for answers — this science is changing everything. Indiana's FIGG unit continues to grow. The expansion to include part-time civilian investigators signals the state's commitment to this methodology. More cases are coming. Indiana's cold cases are falling. One by one.
