How uploading DNA to genealogy sites helped ID Gilgo victim Valerie Mack

Genetic genealogy, once only of interest to people curious about finding their long lost relatives, has become one of law enforcement’s most sought-after forensic tools for solving difficult cases.

In the past few years, police across the country and in Canada have enlisted the services of genealogists to help solve 150 to 200 cases of homicide and missing persons cases, genealogist Colleen Fitzpatrick, who runs Identifinders International, said.

Also known as investigative forensic genealogy, genetic genealogy involves comparisons of crime scene DNA to genetic samples that have been uploaded to public genealogical databases such as GEDmatch to find similarities indicating kinship. Professional genealogists then construct family trees to uncover familial relationships that might identify a suspect or a missing person.

On Long Island, the most widely publicized case recently was when the Suffolk County Police Department and the FBI used the method to identify in May 2020 Gilgo Beach victim Valerie Mack, 24.

Valerie Mack, "Jane Doe No. 6"

Mack was 24 and had been working in Philadelphia as an escort when she disappeared. Her remains first were found in Manorville in 2000, and then more of her remains were discovered 11 years later, near Gilgo Beach.

Publicity on genetic genealogy soared in 2018 when police in California arrested Joseph John DeAngelo Jr., also known as the "Golden State Killer," in a string of homicides and rapes in the 1970s and 1980s. Crime scene DNA allowed investigators to find his relatives, and police made a definitive match to DeAngelo’s DNA. DeAngelo, 75, pleaded guilty in June to 13 murders and was sentenced to numerous life sentences.

Here are some additional recent examples of cases solved through genetic genealogy:

Calvin Hooper: Police in Toronto, Canada, struggled for years to make a case in the 1984 sex assault and murder of 9-year-old Christine Jessop. The conviction of one suspect was overturned after DNA found on the girl’s underwear exonerated him. Using genetic genealogy, Toronto police zeroed in on Hoover, who had been an earlier person of interest. The genealogists constructed family trees that led to the identification of Hoover in October 2020 as Christine’s killer. Hoover had died in 2015.

Joseph Wayne Burnette: The body of Dana Lynn Dodd was found burned on a wood pile in Gregg County, Texas, in October 2006. She remained unidentified until the DNA Doe Project used genetic genealogy to identify her in 2019. Then, Burnette, a prior sex offender, admitted killing Dodd and, separately, his girlfriend. His attorney said he has pleaded not guilty and that plea negotiations are underway with a disposition expected on Dec. 15.

Steven Branch: Jessica Baggen, 17, of Sitka, Alaska, never made it home from her girlfriend’s house and was found dead on May 6, 2006. One man confessed to killing Jessica, but with no evidence to corroborate his story, he was acquitted. DNA found on Jessica’s body was used through genetic genealogy to make Branch a person of interest. Branch had moved to Arkansas, and after police there asked for a DNA sample in August 2020, he refused. Branch, 66, killed himself a half-hour after police left his home. DNA from his autopsy matched the sample taken from Jessica.

Johnny Chrisco: A woman’s body was found beaten, raped and slashed in an Orange County, California, field in March 1968. Partial DNA was found on her clothing, and genealogical testing at the behest of Huntington Beach police determined it came from Johnny Chrisco, who had died in 2015. Further genealogical work by Fitzpatrick finally identified the body as that of Anita Piteau, 26, an aspiring actor from Maine, where she is now buried.

Sources: Interviews, law enforcement statements, news reports.

By Anthony M. DeStefano

tony.destefano@newsday.comtonynewsday

Anthony M. DeStefano has been a reporter for Newsday since 1986 and covers law enforcement, criminal justice and legal affairs from its New York City offices.