Public Safety

Cedar Rapids police use DNA technology to create suspect composite in Michelle Martinko killing

Images unveiled Tuesday could help solve 37-year cold case

An image of the man suspected of murdering Michelle Martinko as he might appear now at age 50 is displayed at a press co
An image of the man suspected of murdering Michelle Martinko as he might appear now at age 50 is displayed at a press conference announcing new technology that could help solve the decades-old murder at the Cedar Rapids Police Department on Tuesday, May 16, 2017. Officials presented computer-generated renderings of the murder suspect that were created using a database of DNA phenotypes, or the physical expressions of genetic code. (Rebecca F. Miller/The Gazette)

CEDAR RAPIDS — For the first time since Michelle Martinko was stabbed to death 37 years ago, her sister and brother-in-law can look the killer in his eyes.

Using the services of a Virginia-based company that uses DNA to predict the physical features and ancestry of a suspect, the Cedar Rapids Police Department has produced images of a man believed to have killed Martinko in Cedar Rapids on Dec. 19, 1979. Those images were shared with Martinko’s sister and brother-in-law, Janelle and John Stonebraker, earlier this month and were shared with the public during a news conference on Tuesday at police headquarters.

“It’s very sobering and disturbing at the same time,” John Stonebraker said, as he stood just feet away from the images. “But, it is also hopeful.”

Added Janelle Stonebraker, “It’s very personal. It brings it to a person.”

Police said Martinko, 18, a Kennedy High School student, was found dead in her family’s 1972 Buick Elantra outside Westdale Mall on Dec. 20, 1979, after being reported missing by her parents. Police said there was no sign of a sexual assault, but she had wounds that indicated she fought her attacker.

The case has gone unsolved, but has been far from forgotten, Cedar Rapids Police Chief Wayne Jerman said during Tuesday’s news conference.

“This police department does not give up on cases,” Jerman said. “They may go cold, but especially with the Michelle Martinko case, we’ve never forgotten about it.”

In October 2006, police investigators announced they had developed the suspect’s DNA in the case. The DNA was uploaded to the national Combined DNA Index System, but it did not produce a match. Over the years, various other tips have come in, but produced no arrests in the case.

Investigator Matt Denlinger said investigators reached out to Parabon NanoLabs in September 2016 to use their Snapshot DNA Phenotyping service, which is used to create a suspect composite based on DNA traits. The service cost $5,000.

“They give you predictions for skin color, eye color — even freckling,” Denlinger said. “This is not an inexpensive process. We took this on because we thought we could accomplish something with it.”

Dr. Ellen Greytak, of Parabon NanoLabs, said the composite is a likeness of a suspect, “not a photograph of a person.” She said the Snapshot service is especially useful in narrowing the suspect pool through exclusion.

“What we’re doing is really narrowing it down,” she said.

With the DNA obtained in the Martinko case, Parabon NanoLabs created a composite of a light-skinned man with blond hair and blue or green eyes. The images were also aged to visualize what the suspect might look like at age 50.

Cedar Rapids public safety spokesman Greg Buelow said police have used the composites to eliminate some potential suspects. They are now presenting the composites to the public in hopes of generating more leads.

Buelow also said the police department has received several inquiries from the public on how they can donate to a reward fund assigned to the Martinko case. He said tax-deductible donations can be sent to Linn County Crime Stoppers, c/o the Cedar Rapids Police Department, 505 First St. SW, Cedar Rapids, IA 52404. Those who write checks should put “Martinko cold case” in the memo section.

Linn County Crime Stoppers currently has a $5,000 reward, Buelow said, adding an anonymous donor is willing to contribute an additional $10,000 to the reward fund and is hoping the public will match that donation.

“We owe it to the Martinko family and we owe it to Michelle that we find out who is responsible for her murder,” Jerman said. “This is a great shot for us to accomplish that ... I believe through this exposure, it’s going to give us that opportunity.”

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