CEDAR RAPIDS, Iowa (KCRG) -- Recently unsealed court documents detail what led police to the man they believe killed Michelle Martinko nearly 40 years ago.
Jerry Burns, 64, of Manchester (Courtesy: Cedar Rapids Police Department)
Martinko was found murdered in her family's car outside the Westdale Mall in Cedar Rapids in December of 1979.
Prosecutors charged 64-year-old Jerry Burns in her death just last year.
In all, there are two search warrants that have been made apart of the public record.
Both warrants were issued in December and mention Burns by name. They also make it clear DNA played a central role in the police investigation.
One warrant seeks to allow investigators to examine and photograph Burns. Authorities say in the warrant they were looking to see if Burns had any scars as a result of the struggle they believe occurred between Burns and Martinko.
Matthew Denlinger with the Cedar Rapids Police Department explained in court documents that new developments in DNA matching led them to a woman in Vancouver, Washington who was believed to be a possible 2nd cousin to the suspect. Genealogical research then led them to a first cousin and then to Jerry Burns and his two brothers.
Denlinger says he was able to "covertly" collect discarded items from the relatives that possibly had their DNA on it. It was a drinking straw Burns threw away that allowed investigators the opportunity to test his DNA.
The other warrant was to collect DNA directly from Burns so investigators could compare it with the sample they first collected.
Investigators say more than 125 DNA samples were collected during the course of the investigation. All of those individuals have been cleared.
A case management conference in Burns' case is scheduled to take place in May.