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DNA transfer in Fauquier county: The CVS murder

Warrenton, VA

On July 26, 2017, manager Rex Olsen was found dead near a dumpster behind his CVS store. He had been shot in the head and face. Passed over for promotion, assistant manager Bernard Duse became a suspect. Cell tower records showed victim and suspect’s mobile phones traveling together towards Duse’s home after the murder.

The Virginia Department of Forensic Science found a DNA mixture in the victim’s left pants pocket, where he kept his phone. The crime lab’s TrueAllele® technology found a mix of 85% Olsen and 15% Duse, linking the victim’s pocket to the suspect with a match statistic of 40 quintillion.

Duse’s defense lawyer theorized DNA transfer, suggesting that (1) his client touched an object in the CVS office, with (2) the victim touching it afterwards then (3) innocently transferring Duse’s DNA into his phone pocket. Commonwealth’s Attorney James P. Fisher asked Cybergenetics to complement the crime lab’s evidence by teaching the true DNA science in court.

“In the recent case of Commonwealth of Virginia v. Bernard C. Duse, Jr., our jury had the good fortune to hear from Dr. Mark Perlin,” said CA Fisher. “His expert testimony on DNA analysis, interpretation and the emerging study of DNA transfer was vital for their deliberation.”

CA Fisher said the jury “promptly, and justly, returned a verdict of guilty for first-degree murder after two hours of deliberation. We are grateful for Dr. Perlin’s extraordinary professionalism and expertise in this matter. It was vital for the jury to reasonably know and understand the truth on a complicated scientific matter, and his testimony shined a bright light on that truth.”

Crime laboratories develop DNA data from biological evidence. Some use TrueAllele computing to find accurate and objective match statistics. Cybergenetics complements crime lab capabilities with advanced science and effective communication.

  • Employee at Virginia CVS charged with killing manager - NBC Washington
  • Victim’s widow and cops testify about CVS murder - Fauquier Now
  • Jury returns guilty verdict in CVS murder case - Fauquier Now
  • Jury recommends life in prison for CVS murder - Fauquier Now

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