
The Same Blood
Years ago, I spit into a small test tube and mailed off my sample to a DNA company very much like the one in my soon-to-be released thriller, The Wrong Family. Weeks later, I learned that I am likely to have detached earlobes, few freckles, and a longer big toe. I am more likely to be afraid of heights; more likely to experience motion sickness; and more likely to be bitten by mosquitos. All true, by the way. As of today, I have over 1,500 DNA relatives, spanning the entire globe. A fourth cousin in New Zealand? Who knew? And among those relatives, is there a murderer?
DNA technology is a hidden roadmap, a 46-chromosome clue, that allow us to explore the mysteries of ourselves and our origins. But it hasn’t been without controversy, particularly when it concerns the application of DNA technology to crime-solving. In recent years, law enforcement has begun using DNA to unravel some of the most perplexing and gruesome cases. The largest genealogy databases, AncestryDNA, 23andMe and My Heritage, do not permit law enforcement to input DNA from crime scenes or unknown victims; however, there are no prohibitions against the use of DNA from a family member to solve a case.
In 1958, in Omaha, Nebraska, sixteen-year-old William Arnold killed his parents and buried them in the backyard, after they refused to let him borrow the family car. Arnold was arrested a few weeks later and confessed to the murders, even leading authorities to the makeshift gravesite. He received two life sentences in state prison but escaped eight years into his term by fleeing out a window of the prison’s music room and shimmying over a twelve-foot razor wire fence, using a T-shirt to protect himself from the barbs. Arnold was in the wind, disappeared forever. Or was he? In 2020, a deputy marshal in Nebraska began to reexamine the case and obtained a DNA sample from Arnold’s youngest brother. Cross-referencing the sample on an ancestry site, he waited for several years before he got a hit. An alert from a man in Chicago who was searching for his biological father. Unbeknownst to him, his father was William Arnold. Though he had died in 2010, Arnold had lived for years under an alias in Australia, where he had married twice and fathered two children.
The Golden State Killer, Joseph DeAngelo, was also unmasked with the help of DNA technology. In 2020, DeAngelo—a former police officer—pled guilty to numerous violent crimes, including the murders of thirteen people, and admitted to numerous rapes and burglaries that occurred in the 1970s and 1980s. He had long eluded detection, and his unsolved crimes had captured the attention of the late Michelle McNamara, who wrote about his violent exploits in her true crime book, I’ll Be Gone in the Dark. When DeAngelo was first arrested, it was reported that authorities had relied on family tree searches to identity him. A detective confirmed that investigators had used semen from a rape kit to develop a DNA profile, which was then uploaded to an open-source DNA platform called GEDmatch. It was later disclosed that two other DNA companies were involved, including one that had allowed law enforcement to set up a fake account to search for potential matches for their sample. Similar technology also led to the apprehension of the NorCal Rapist.
Most recently, Brian Kohlberger, who was charged in the brutal murders of four University of Idaho students, was identified possibly using a DNA sample he submitted himself in an effort to learn more about his heritage. After collecting DNA from Kohlberger, investigators ran the sample through a public database and used genealogy techniques to track their suspect through his family members.
As the main character in The Wrong Family, Hallie, realizes in her search for her long, lost father: DNA technology can be used for good or evil. And good and evil are largely in the eye of the beholder. So, think carefully before you spit into that tube and mail off the key to your identity. You never know who you’ll shake out of your family tree or who might come looking for you one day. One thing is certain: It’s becoming harder and harder to get away with murder.