The Yarborough homicide was first attempted in 2011 by comparing the Y-STR profile obtained from crime scene DNA to public Y-STR genetic genealogy databases. When the case was solved in 2019 using autosomal SNP testing, it was discovered that Sarah’s killer could have been identified at least twenty years earlier through CODIS, but loopholes in the legal system had allowed him to avoid detection.
The 2019 identification of Patrick Nicholas as a suspect using autosomal SNP testing raised awareness of the limitations of CODIS, and fueled debate over the role of familial searching versus forensic genetic genealogy. Nicholas was convicted in 1983 of attempted first-degree rape in Benton County, WA before CODIS was launched in the 1990s. In 1993, he was arrested again for first degree child molestation. Although his DNA profile should have been entered into CODIS, he was allowed to plead to gross misdemeanor that did not require DNA collection. He escaped detection a second time. After Nicholas ’arrest, it was discovered that his brother Edward had already been entered into CODIS for a prior conviction for rape in the first degree; he was also a registered sex offender. Because Washington does not practice familial searching, Patrick Nicholas had escaped detection a third time.
Upon Nicholas’s identification using genetic genealogy, King County Sheriff’s Office quickly secured his DNA from discarded cigarettes. His DNA was found to be a CODIS match to the DNA profile developed from the victim. Nicholas has been charged with first degree murder with sexual motivation. He is currently pending trial in King County Superior Court, Seattle, Washington.
Although the case became one of the first to use autosomal SNP testing in 2014, the type of SNP analysis that was available to the forensic community at that time was primitive compared to the Direct-to Consumer (DTC) genealogical techniques used today, so it did not prove very useful.
By 2019 however, genetic genealogy had finally advanced and succeeded where the legal system had failed. The perpetrator, identified as Patrick Leon Nicholas, had escaped CODIS identification three times, thanks to loopholes in the legal system. Ironically, since Sarah’s killer was named Nicholas and not Fuller, it also pointed out the limitations and need for judicious use of all tools, including Y-STR analysis.
His grandfather was adopted. This meant that his legal surname was not his biological surname, highlighting the fact that even genetic genealogy has its loopholes.
The cold case solves that appear in the headlines today may be exciting news, but they are the product of a slow and steady development of the forensic use of genetic genealogy. And it all started with a young woman named Sarah.