– A decades-old cold case has been solved thanks to advancements in forensic genealogy and the persistence of investigators who revisited evidence with modern technology. James Unick, 64, was recently found guilty of the 1982 murder of 13-year-old Sarah Geer in Cloverdale, California, a case that remained unsolved for nearly 44 years. The breakthrough came from DNA extracted from a discarded cigarette butt.
The Power of Genetic Genealogy
The case highlights the growing power of genetic genealogy, a technique that combines DNA analysis with traditional genealogical research. This method gained prominence in with the arrest of the Golden State Killer, and has since been instrumental in resolving numerous other cold cases, including a murder in Wisconsin and a murder in Washington state.
In Geer’s case, investigators initially developed a DNA profile in from sperm collected from the victim’s clothing. However, at the time, the available forensic science wasn’t sufficient to identify a suspect. The case remained dormant for years until investigators, in late , partnered with a private investigation firm to re-examine the evidence using the latest advancements in cold case work.
From Familial DNA to a Cigarette Butt
The FBI played a crucial role in the investigation. Utilizing familial genealogical databases, they determined that the DNA evidence linked to Sarah Geer belonged to one of four brothers, including James Unick. This narrowed the focus of the investigation significantly. Investigators then conducted surveillance on the Unick brothers and collected a discarded cigarette smoked by James Unick.
A subsequent DNA analysis of the cigarette confirmed a match to the DNA profile obtained from the crime scene, as well as other DNA samples collected from Geer’s clothing. This provided the conclusive evidence needed to secure a conviction.
The Technical Process: Bridging the Gap Between DNA and Identity
Genetic genealogy doesn’t provide a direct name match. Instead, it works by identifying distant relatives of the suspect through publicly available genealogical databases. These databases contain DNA profiles voluntarily submitted by individuals for ancestry research. By analyzing shared DNA segments between the crime scene evidence and the database profiles, investigators can build family trees and identify potential suspects.
The process relies on the fact that DNA is inherited, and relatives share portions of their genetic code. The more DNA shared, the closer the relationship. Investigators then use traditional investigative techniques – such as surveillance and obtaining direct DNA samples – to confirm the identity of the suspect. The cigarette butt in this case served as that crucial direct sample.
Challenges and Implications
While genetic genealogy has proven to be a powerful tool, it’s not without its challenges. The accuracy of the results depends on the size and diversity of the genealogical databases. Privacy concerns have been raised regarding the use of personal genetic information in criminal investigations. The legal and ethical implications of this technology are still being debated.
The Sonoma County District Attorney, Carla Rodriguez, emphasized the significance of the verdict, stating, “This guilty verdict is a testament to everyone who never gave up searching for Sarah’s killer.” She also noted that this was “the coldest case ever presented to a Sonoma County jury,” underscoring the difficulty of solving crimes decades after they occur.
The successful prosecution of James Unick serves as a powerful example of how advancements in forensic science, combined with dedicated investigative work, can bring closure to families and deliver justice in even the most challenging cold cases. The case also demonstrates the evolving landscape of criminal investigation, where technology plays an increasingly vital role in uncovering the truth.
