GRAND JUNCTION, Colo. (CBS4)– The Grand Junction Police Department says a 45-year-old cold case has been solved. The investigation involved the homicide of 19-year-old Deborah Tomlinson.

It was Dec 27, 1975 when Grand Junction Police officers responded to an apartment complex in the 1000 block of Belford Avenue. A caller had said a woman was dead inside one of the units. Officers found Tomlinson, who had been bound, sexually assaulted, and strangled.

Deborah Tomlinson (credit: Grand Junction Police)

Detectives were unable to find enough evidence and the case went cold. In 2019, the homicide case was given a fresh look by detectives.

In 2020 police sought the services of Parabon NanoLabs, a DNA technology company in Virginia.

In Tomlinson’s case, Parabon analyzed a genetic data profile created from the unknown crime scene DNA sample and compared the results to a public genetic genealogy database. Parabon was able to narrow down the possibilities before a final list of leads was produced.

The Grand Junction Police Department then used traditional police work to identify Jimmy Dean Duncan as a suspect. Detectives obtained DNA from one of Duncan’s relatives and submitted the sample for comparison with the original DNA evidence that was found at the crime scene. The Colorado Bureau of Investigation confirmed that the DNA samples matched.

Duncan was not identified as a suspect in the investigation prior to Parabon’s findings. Duncan, a Colorado native who was 26 at the time of the murder, died in 1987.