Forensic Analyst Says Suspect's DNA Is 'Consistent' With DNA Found On Martinko's Dress
A witness testified in Davenport Monday that DNA from the suspect in a 40-year-old murder case is “consistent” with DNA found on the dress the victim was wearing when she died. The testimony from a forensic DNA analyst came in the case of Jerry Lynn Burns, who faces a first degree murder charge for the killing of Michelle Martinko in Cedar Rapids in 1979.
Prosecutors have made DNA evidence central to the case against Burns, drawing on analyses of items collected from the crime scene more than 40 years ago. Early on the morning of December 20, 1979, 18-year-old Martinko was found stabbed to death in her family’s Buick, which was parked outside the Westdale Mall. No murder weapon has been found and prosecutors have not established a relationship between Burns and Martinko, describing her killing as a “random act of violence committed by a stranger."
On Monday, Michael Schmit of the Iowa Department of Criminal Investigation testified about DNA found at the crime scene that prosecutors say links Burns to the killing.
As a criminalist at the DCI laboratory in Ankeny, Schmit analyzed DNA from a cheek swab that investigators obtained from Jerry Burns in December 2018.
Schmit testified that the genetic material from the cheek sample is consistent with a male genetic profile developed from DNA found in a bloodstain on Martinko’s dress. Schmit testified that the odds of another person having this same genetic profile is incredibly rare.
“So for this case, the probability of finding this profile in a population of unrelated individuals chosen at random would be less than one out of a hundred billion,” Schmit testified. “It’s kind of like, what would be your chances if you were playing a lottery where you had to correctly guess 12 numbers at random?”
Investigators first identified Burns as a potential suspect following extensive research based on previous genetic analyses. Another DCI analyst, Linda Sawer, identified male DNA in a bloodstain on Martinko’s dress and developed a genetic profile from the sample in 2005.
"There were still more people in these files that we could get names from and maybe go track down and follow up on and collect from them and eventually, hopefully we could find a match [...] unfortunately we didn't find a match by just following that path." - Investigator Matt Denlinger, Cedar Rapids Police Department
Initially, Cedar Rapids Police Department Investigator Matt Denlinger, who took on the case in 2015, hoped he’d be able to find a match based on the profile Sawer developed and the case files alone.
“There were still more people in these files that we could get names from and maybe go track down and follow up on and collect from them and eventually, hopefully we could find a match,” Denlinger said. “Unfortunately we didn’t find a match by just following that path.”
Denlinger decided to take the DNA profile from the dress to a private, Virginia-based firm, Parabon NanoLabs to develop an illustration or “snapshot” of what the suspect could have looked like in 1979. Denlinger testified Monday that the company, along with the Florida-based firm DNA Labs International, conducted further analyses.
Parabon NanoLabs uploaded the male profile from the dress to the public genealogy website GEDmatch. The subject was found to be a second or third cousin once removed of Brandy Lee Jennings of Vancouver, Washington. Parabon NanoLabs created genealogy and kinship reports and developed a family tree of the subject’s relatives, stemming from four sets of great grandparents.
Denlinger said he worked to track down the descendants on the branches of the family tree, obtaining DNA samples from them to be compared to the male profile.
“If I was able to collect DNA from a living relative on each branch of that tree and send those swabs back to them then they could tell which branch of the family tree our suspect was on,” Denlinger said. “I did a total of three [branches]. I eliminated two and on the third one is when we got our hit.”
Parabon NanoLabs researchers ultimately hypothesized that the subject was likely one of three brothers: Kenneth, Donald and Jerry Burns, all originally of Manchester, Iowa. Investigators then tracked the men in order to covertly collect DNA samples from them.
"It was just kind of unbelievable that the type of technology to get us to this point even existed. It seemed kind of science fiction to me." - Criminalist Michael Schmit, Iowa Department of Criminal Investigation
For Donald, they picked up a bag of his garbage after he put his bin on the curb, including a straw with a lid, a used toothbrush, and a bloody bandage. For Kenneth and Jerry, they followed each of them individually, tracking them until they each went to a restaurant. Investigators sat at tables near them while they ate, and then grabbed straws they had used after they left the restaurants.
When Schmit tested the straw labeled as Jerry Burns’, the genetic profile he developed from the sample was consistent with the profile from Martinko’s dress. At that point, he had already analyzed samples from “at least 30” other persons of interest in the case without finding a sample that was consistent. Schmit testified that he considers the moment a significant break in the case.
“It was just kind of unbelievable that the type of technology to get us to this point even existed,” Schmit said. “It seemed kind of science fiction to me.”
After Schmit determined the profile from the straw was consistent with the profile from the dress, investigators obtained a search warrant for a cheek swab from Jerry Burns and went to interview him in Manchester. A criminal complaint filed in the case shows that during the interview, Burns denied being at the scene of the crime but “could not offer any plausible explanation why his DNA would be found at the crime scene." It was after this interaction in December of 2018 that law enforcement officers took him into custody.
Burns has pleaded not guilty to the first degree murder charge. His legal team has posed questions about whether evidence in the case has been properly handled since 1979.
CRPD investigators have testified that evidence from the Martinko case that was stored in the basement of the department sustained water damage during the catastrophic flood of 2008. (Other samples from previous analyses of evidence from the case were securely stored at the DCI lab in Ankeny).
There was also a period of time in 2016 when another officer couldn’t find the evidence package containing Martinko’s dress because it was sitting on Denlinger’s desk, instead of being returned to the CRPD evidence room for long-term storage.
Still, based on the genetic analyses by the DCI, investigators were able to eliminate multiple potential suspects from the case, including Jerry Burns’ brothers. Schmit testified that more than 100 persons of interest were eliminated due to their genetic profiles not being consistent with the profile from the dress.
Schmit said based on technical guidelines from the DCI, he cannot say that the DNA from Burns’ cheek swab “matches” the DNA found on the dress because some of the genetic profile from the crime scene didn’t show up on the test. But he says at all available testing locations or “loci” on the DNA molecule that his kit could test for, the genetic material from Burns’ cheek swab is consistent with the material from the dress.
“A match at 12 loci I would only expect to come from an identical twin of Jerry Burns,” Schmit said.
Burns does not have an identical twin.