Over the course of 32 years, Minnesota investigators interviewed and collected DNA from more than 100 people but were never able to link anyone to the rape and murder of 38-year-old Nancy Daugherty, a mother, nursing home aide and first responder. Recent genetic genealogy efforts have changed that, leading to the arrest of a 52-year-old local man named Michael Carbo, Jr.
Daugherty was last seen alive shortly after midnight July 16, 1986. After she failed to get in touch with family, the Chisholm (Minnesota) Police Department found her in her home beaten, raped and strangled to death. Evidence at the scene indicated a struggle had occurred both outside and inside the home, and witnesses later reported hearing a woman screaming in the early morning hours.
The other component left at the scene was DNA. In fact, after initial analysis, investigators had multiple full DNA profiles recovered from one individual. However, the DNA did not match anyone in CODIS.
In early 2020, Chisholm Police Chief Vernon Manner, with the help of the Bureau of Criminal Apprehension (BCA), provided a sample of DNA to Parabon. In July, Parabon identified Carbo as a potential suspect in the case.
BCA agents and Chisholm investigators then surreptitiously obtained DNA evidence that was sent to the BCA laboratory for analysis. On Monday, July 27, the BCA laboratory reported a DNA match to the bodily fluids found on the victim and at the scene. On Wednesday, July 29, Carbo consented to a DNA sample, which was immediately tested and matched to the crime scene. By Wednesday’s nightfall, investigators had already arrested Carbo, who was 18-year-old at the time of the crime.
“The known sample matched to those from the crime scene long ago, finally providing the key piece of evidence,” BCA Superintendent Drew Evans said during a press conference. “These cases are never cold in our eyes. Every time we examine a piece of evidence or technology advances, investigators look at the case again to see if we can provide additional information and answers.”
“Some of the investigators have worked on this case their entire careers,” noted chief Manner.
Photo: The victim, Nancy Daugherty. Credit: Minnesota BCA