PROVIDENCE, R.I. — DNA evidence left behind 35 years ago and the use of forensic genealogy has led to the arrest of an Indiana man on charges that he sexually assaulted two Rhode Island girls in 1987, authorities announced Wednesday.
Frank Thies, 66, of Terre Haute, Indiana, is scheduled to be arraigned Thursday in Rhode Island on charges of sexual assault and molestation, according to the Rhode Island State Police.
The victims, aged 11 and 13, were sexually assaulted in April 1987 after their attacker forced them into the woods in rural Rhode Island, police said. One of the girls lived nearby in Exeter. Police recovered physical evidence that they believed came from the perpetrator, but could not make an identification.
The case was reopened in 2005 following advancements in genetic forensics, but still no match was found.
In 2019, detectives with the state’s Special Victims Unit worked with the Rhode Island Department of Health to reexamine the genetic evidence once again. They turned to genetic profiling, which involves searching DNA databases to find familial matches to the DNA of a suspect. From there, they determined the suspect was likely one of three brothers from western New York who had served in the military.
Investigators then teamed up with the Naval Criminal Investigative Service and found that one of the brothers had visited the Naval Justice School in Newport the day before the assault. Authorities in Indiana obtained a discarded sample of the suspect’s DNA, which police say matched the evidence recovered 35 years ago.
Thies was arrested Oct. 19 in Indiana and was extradited to Rhode Island. He is charged with one count of first-degree sexual assault and two counts of first-degree child molestation.
It was unclear Thursday if Thies is represented by an attorney who could comment on the charges.
Forensic genealogy received widespread attention in 2018 after it was used to track down a California serial killer who was responsible for at least 13 killings and dozens of rapes in the 1970s and 1980s. Since then, the new method has led to the identification of dozens of suspects in cold cases, though some critics have voiced privacy concerns about the practice.
