HOW A YOUNG WOMAN STABBED TO DEATH HELPED SOLVE HER OWN MURDER NEARLY 40 YEARS LATER

"48 HOURS" INVESTIGATES IN "MURDER AT THE MALL: THE MICHELLE MARTINKO CASE"

Saturday, Nov. 7

Michelle Martinko was an 18-year-old high school senior who went out to the local mall in Cedar Rapids, Iowa, on Dec. 19, 1979. She was later found dead in her car. The case baffled local police officers for decades, and kept them going through several generations, until they got a break from evidence Martinko left behind.

Jamie Yuccas and 48 HOURS investigate what happened that night and take viewers inside the unrelenting efforts by police to solve the case in "Murder at The Mall: The Michelle Martinko Case" to be broadcast Saturday, Nov. 7 (10:00 PM, ET/PT) on the CBS Television Network.

As Martinko left the mall that night just days before Christmas, someone snuck up on her as she sat in her car, opened the door and climbed in. Martinko was stabbed and cut 29 times. Investigators looked at those closest to her as possible suspects, and questioned many of her male friends. But friends and family were suspicious of an ex-boyfriend. They say he was possessive of her and investigators learned he was at the mall that night.

The crime scene in the parking lot was gruesome.

"This was a real fight," says Detective Matt Denlinger. "It looks personal, it's a lot of stab wounds, it's overkill."

Police brought her ex-boyfriend in for questioning but learned that he had an alibi. There was also no hard evidence tying him to the crime.

Over time, leads starting drying up. But police kept at it. The case came alive again in 2005 when blood scrapings from the gearshift of Martinko's car were sent out for testing. That lab report turned up male DNA - DNA that did not match her old boyfriend, anyone previously interviewed in the case, or anyone in the nationwide database of criminal offenders. It would take another decade - and a new detective. Remarkably, he was the son of one of the original detectives on the case and he landed the big break long sought by his father. He turned to Parabon NanoLabs, which uses genetic genealogy to track DNA from one family member to another. Parabon found a distant relative of the killer.

Investigators then set out to painstakingly build a family tree. One branch of that tree led to three brothers, all of them living nearby. After secretly getting samples from all three, they had a match. Even the police were shocked.

"I was definitely speechless. I'm almost speechless today thinking about it," Denlinger says.

Then, 39 years to the day after Martinko was murdered, Denlinger using a camera hidden in a coffee mug sat down with suspect Jerry Burns, a married father and businessman, to talk about that fateful night in December 1979 at the Westdale Mall.

Did investigators have their man?

Something interesting that Burns said to police in that interview also left them wondering about another famous Iowa case.

"I just seen something about Jodi Huisentruit recently ... ," Burns told them, randomly mentioning the name of an Iowa news anchor kidnapped near her car in a parking lot in 1995 and never found. There is no evidence that Burns knew the TV reporter, but the mere mention of her name is intriguing.

48 HOURS: "Murder at The Mall: The Michelle Martinko Case" is produced by Alec Sirken, Jamie Stolz and Matthew Goldfarb. Lincoln Farr is the development producer. Ken Blum, Doreen Schechter and Michelle Harris are the editors. Lourdes Aguiar is the senior producer. Nancy Kramer is the executive story editor. Judy Tygard is the executive producer.

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