Sarah Yarborough

Case background and investigation

On the morning of December 14, 1991, 16-year-old Sarah Yarborough drove to Federal Way High School, south of Seattle, Washington, arriving early for a drill team competition. She never made it inside. Her body was found in a brushy area on the school grounds, roughly 300 feet from her parked car; she had been sexually assaulted, beaten, and strangled, with her clothing scattered nearby. A 13-year-old boy and his friend, cutting across the grounds, discovered her body, and the boy reported having seen a man emerging from the bushes moments earlier. Composite sketches were released, but the case soon stalled.

Investigators recovered a full male DNA profile from Sarah's clothing, but for two decades it produced no match in CODIS, the national database of convicted offenders. Despite more than three thousand leads over the years, the murder of the popular, high-achieving teenager went cold, becoming one of the Seattle area's most notorious unsolved crimes and a source of lasting grief for her family and community. Detectives kept the biological evidence carefully preserved, betting that advances in DNA science would one day give them a name even as conventional leads ran dry.

The case became a landmark in forensic science. In 2011, detectives worked with genetic genealogist Colleen Fitzpatrick, and by comparing the killer's Y-chromosome profile to public genealogy databases they traced his paternal line to the surname Fuller — descendants of a man who had come to America in the 1600s. That early work, among the first uses of genetic genealogy in a criminal case, generated attention but did not immediately identify the killer. Years later, using more advanced autosomal DNA analysis, Fitzpatrick's team narrowed the search to two brothers, and in 2019 the evidence pointed to Patrick Nicholas.

To confirm the match, undercover King County detectives followed Nicholas and collected cigarette butts and a napkin he discarded at a laundromat; testing showed his DNA matched the profile from the crime scene. Nicholas, who had a prior record of sexual assaults but had repeatedly slipped through gaps that kept his DNA out of the offender database, was arrested and charged. At trial in the spring of 2023, prosecutors presented the DNA evidence along with items found in his home, and on May 10, 2023, a jury convicted him of first- and second-degree murder with sexual motivation. He was sentenced to nearly 46 years in prison, closing a case that had haunted the Federal Way community for more than three decades. The Yarborough investigation is now widely cited as a milestone in the use of forensic genetic genealogy: the same techniques that traced the killer's colonial-era ancestry would later be refined and applied to identify suspects in dozens of long-cold homicides across the country, and Sarah's family, who waited more than thirty years for an answer, became advocates for the technology that finally delivered one.