After 35 years, Fairfax Co. police make arrest in case of rapist who posed as radio DJ

Fairfax County Police Chief Kevin Davis announces the arrest of William Clark, April 20, 2022.

Thirty-five years ago, a man on the phone posing as a popular radio DJ offering a free trip to Hawaii lured a 14-year-old Fairfax County, Virginia, girl out of her house and raped her.

Detectives had DNA evidence the perpetrator left behind and over the years, they investigated — and ruled out — more than 70 potential suspects. Still, the crime went unsolved.

On Wednesday, Fairfax County police announced they have finally made an arrest in the 1987 case, crediting the use of forensic genealogy.

“Here we stand in 2022 announcing that a violent, vicious criminal who perpetrated this heinous act on a 14-year-old girl is now in custody … and finally being held accountable for his crimes three and a half decades ago,” Fairfax County Police Chief Kevin Davis told reporters during a news conference Wednesday.

William Clark, 59, of Ashburn, has been charged with rape, abduction with intent to defile and attempted forcible sodomy. He is being held without bond at the Fairfax County jail.

Officials said it was the first arrest in the county tied to the use of forensic genealogy, which involves building a family tree from the DNA evidence perpetrators leave behind and online ancestry databases.

Maj. Ed O’Carroll, bureau chief of the major crimes bureau, said Clark, who was then 24, engaged in an elaborate ruse to carry out his attack on the girl.

The ruse

First, in what appeared to be a random phone call, he called the girl’s mother at her workplace posing as the DJ and saying she was eligible to win $1,000 and a free trip to Hawaii if she listened to the radio station. The woman provided her home phone number as contact information.

When Clark called that number, he spoke with the woman’s daughter and convinced her to drive to another radio station in Fairfax City, O’Carroll said. Once there, he enticed her to get inside his car with the promise of the prizes, then drove her to a wooded area and assaulted her before driving off.

At the time, investigators were able to collect DNA evidence, which never pointed to a suspect but was used to rule out the several dozen potential suspects investigated over the years.

“We never gave up,” O’Carroll said, saying investigators kept picking up the case over the years.

Clark, who lived in Herndon at the time, was never on detectives’ radar until he was identified as a “strong person of interest” in January after the department began using forensic genealogy, O’Carroll said.

In February, detectives obtained a DNA sample from Clark, which was analyzed by scientists at the Virginia Department of Forensic Science. It matched the 1987 evidence, O’Carroll said.

Clark was arrested Monday.

The science

At the news conference Wednesday, officials offered few details of exactly how detectives identified Clark.

O’Carroll said the department has a few genealogy experts among its staff and also works with private companies.

Forensic genealogy involves comparing the genetic profiles of suspects with samples voluntarily uploaded to online genealogy databases. The practice rarely identifies perpetrators directly, but investigators use the leads generated to begin piecing together a family tree of their unknown suspect.

“We have companies that we partner with to get us in the right direction, but at the end of the day, it’s not guesswork. … We always rely on the scientific evidence,” O’Carroll said.

He also declined to say how detectives obtained Clark’s DNA, which was compared to the 1987 evidence, other than to say they collected it “legally.”

The victim in the case has never been publicly identified and would now be in her late 40s. “I’m sorry you endured this crime so many years ago,” O’Carroll said.

He said detectives have been in touch with the woman recently.

“I don’t want to put words in her mouth but I do understand she was pleased — pleased with the Fairfax County Police Department … to get Clark in handcuffs,” O’Carroll said.

Detectives are considering the possibility that Clark may be connected to other sexual assaults in the 1980s.

“This case happened a long time ago,” O’Carroll said. “But there may be more survivors out there. So, call us if you have any information about this case, or you think — years or decades ago — you ran into this offender. … You will be believed. These crimes have no statute of limitations.”

Clark is next due in court July 8.

Jack Moore

Jack Moore joined as a digital writer/editor in July 2016. Previous to his current role, he covered federal government management and technology as the news editor at, part of Government Executive Media Group.

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