Cold case solved: DNA and genetic genealogy convict killer after 42 years

A 44-year-old murder case has finally reached its conclusion after James Unick was convicted of killing 13-year-old Sarah Geer in 1982. The breakthrough came through genetic genealogy, linking Unick's DNA from a discarded cigarette butt to evidence found on Sarah's clothing. On February 13, 2024, a jury found him guilty of murder, ending decades of uncertainty for her family.

Sarah Geer was last seen leaving a friend's house in Cloverdale, California, on May 23, 1982. The next morning, her body was discovered in a secluded area—she had been raped and strangled. At the time, her death was ruled a homicide, but with limited forensic technology, no suspect was identified.

In 2003, investigators extracted a DNA profile from sperm found on Sarah's underwear. Though it didn't match anyone in law enforcement databases, the case remained open. Nearly two decades later, in 2021, the Cloverdale Police Department reopened the investigation with the FBI's assistance. Using genetic genealogy, they narrowed the DNA to one of four brothers—including James Unick.

Unick initially claimed he didn't know Sarah or recall the events of her death. However, his story shifted during the trial. The FBI arrested him in July 2023 after matching his DNA from a cigarette butt to the evidence. The jury dismissed his account and convicted him of murder, sentencing him to life in prison without parole.

Since 2018, genetic genealogy has solved numerous cold cases worldwide. Examples include the 2019 identification of Sarah Yarborough's killer in Washington, a 2020 resolution in San Diego County, and the 2024 identifications of Pamela Kay Wittman and Maria Pilar Del Gadillo Carrillo in California. These advancements have transformed how decades-old crimes are investigated.

The conviction of James Unick brings closure to a case that remained unsolved for over four decades. Genetic genealogy played a crucial role in linking him to Sarah Geer's murder, demonstrating how modern forensic techniques can solve even the oldest crimes. Unick will serve a life sentence without the possibility of parole.