FBI uses genetic genealogy to solve 1985 Massachusetts baby murder case

A father and son hunting in the woods found an infant in the snow off Fruit Street in Mansfield, Massachusetts, on January 26, 1985, after spotting footprints in the snow. Federal investigators and Massachusetts authorities used investigative genetic genealogy, DNA testing and a family tree built from the baby’s own DNA to identify Dianne Curry Peck, 59, of Attleboro, as the child’s mother, and she was indicted Monday and arraigned Tuesday in connection with his death.

They first thought they were looking at a doll before realizing the baby boy was lying naked near a rock wall. An autopsy later determined he weighed 6 pounds, was alive at birth and survived only a few hours.

Investigators reopened the case in 2022 with help from the FBI and the Massachusetts State Police Crime Lab. Forensic genetic genealogy let them use the child’s DNA to map relatives and build out the family line that led them to Peck. DNA taken from a soda bottle pulled from the trash outside her home in 2024 matched Peck to the baby's DNA.

Peck told investigators she had delivered the infant in her ex-boyfriend’s car and handed the child to him for adoption, but they found no evidence that account was true. Peck said she had hidden the pregnancy from family, friends and the ex-boyfriend, who died in 2020.

FBI Boston Special Agent-in-Charge Ted Docks said the indictment showed investigators never give up and called the case heartbreaking, saying the baby was allegedly abandoned and left to die by his mother. For more than four decades, the infant had been known only as Baby Boy Doe.