three brothers. we think one of them is the color. >> that they didn't know which one. >> so, you've got a live one? >> we've got live one here. >> what do you think at that moment? >> we're ecstatic. we're ready to go. >> he was sitting at a booth right by the window. there >> you are the next -- ? >> it's hard to enjoy your food when you think you're staring at that killer. >> hello and welcome to "dateline". teenager michelle martinko was blessed with beauty, brings and compassion. but her promising future was cut short when she was savagely murdered. that dreadful night was ice cold, and after four decades, so was her case. then, a stunning scientific breakthrough helped detectives whittled down a list of suspects to unmask a killer hiding in plain sight. here's dennis murphy with "and then there were three". >> it was an act of unspeakable violence. >> it was a really horrific crime. everybody was scared. >> a murder that shattered a family. >> my parents were devastated. my mother eventually did not cool out of the house. >> a who done it that grabbed hold of the city and wouldn't let go. >> it's been a cloud hanging over the community for 40 years. >> a case that touched generations of investigators, who refused to quit until the killer was found. >> we've cared about this family, they cared about solving this murder. they weren't going to give up. and they didn't. >> kurt thomas says he was a lucky kid. he got to grow up in cedar rapids, iowa. it >> was a magical level. we didn't know anything but fun. >> a lot of that fun happened at the mall,. four teenagers, it was the place to shop, eat and hang out. that's where the kids hung, her? >> it was a place you could go at anytime. and it was feebly deal. >> high school senior michelle martinko was normal right. but she did shop and work at one near her home. michelle was a top student, i gifted baton taller, and some in the school choir, along with her friend jane hanson. >> why do you think you guys hit it off as well as you did? >> gus, we had a lot of things in our life that we're parallel. >> was she what used to call a girly girl? or was she a little bit of a tomboy? what do you remember? >> oh, no. she was a girly girl. >> december 19th, 1979, was a big night for michelle. it was for school choirs christmas banquet at the sheraton inn. with her hair done up to perfection and decked out in her favorite black dress and rabbit for court, she looked like an angel. each alicia. her nickname was fara. john is michelle's brother in law. >> it was for a faucet majors. the hairdo. >> with that here. >> so, she was farah. >> the it was a school night, after the banquet, michelle asked jean to go with her to the mall. that jane had homework to do. >> so when michelle said let's go to the mall tonight, jane, that was going to work for you? >> correct. i turned her down. >> so, going solo, michelle got in her parents 1972 buick electra and headed off to the brand new westdale mall on the southwest side of town. she had $180 cash on her to pay for equal her mother had picked out. kurt was also at the mall that night, working a shift at the men's store. >> i saw this beautiful girl and a rabbit for quote, black dress, high heeled shoes, blonde here. then i was like, that's michelle. >> kurt and michelle were friends from school. she joined him for his break and they went for a stroll. at one point, passing by a shopgirl court had a crush on. teenage drama at the mall. >> and it pops in my head, well, i'm never going to get again, to dance with that girl. because -- >> it got miss america here on my arm? >> yeah. >> curse as he and michelle spent his entire break catching up. until he had to get back to work. and waterton exit. >> and that's when we're seeing our goodbyes. and she said, well, don't be a stranger. >> did you think you see her again? >> yes, of course i did. >> since there was school the next day, it was an a night to stay out late. so, when michel hadn't returned home, even well after the mall had closed, her sister says their mother janet started to worry. >> my parents started calling around to see with her other friends, what the situation was. >> and why she not back here? >> yes. >> and janet did call the police as well. the police say, well, you know we can't look after every teenager who is missing for a couple hours. and janet resisted that. said no, no, she's very dependable. she should be home. she has a testimony. she has to study. >> michelle's mom kept making calls late into the night. at 2:30 am, she dwelled michelle's friend, jane. >> i was sound asleep and my dad came and walk me up. said misses martinko is on the phone. >> those are not good calls. >> she wanted to know if i knew where michel was. >> but jean did not know. nobody did. so, in the middle of the night, in a panic, michelle's mom called the police again. this time, they dispatched and officer. jim kincade got the call out for in. they >> sent me out to the mall to see if i could look at this car. just hours earlier, the mall was bustling with christmas shoppers. now, it was dark. deserted. in the distance, officer kincade spotted a car in the far reaches of the parking lot. a long walk from the entrance to the jcpenney. >> it seemed to match the description. >> looking from your vehicle, could you see what had happened there? >> no. >> couldn't see into the windows? >> could it see into the windows. they were's frosted over. i opened the back door. i could see that there was a woman, slouched down. at first, i thought just an intoxicated person. so, i walked around the car and looked into the passenger side from the window. and obviously, it wasn't an old woman, drunk. could >> you tell she was gone? >> yes. there were no signs of life. she was obviously deceased. >> beautiful, by vicious, high school senior michelle martinko was dead. she was just 18 years old. for her family, and close friends, a christmas season and life as they knew it ended that night. and that brand-new westdale mall had become a crime scene. >> coming up -- what had happened to michelle? >> a very frenzied attack. there was blood everywhere. let's better all in the inside of the car. >> michel had really deep defensive wounds on her hands. she put up a. fight >> against a killer who knew what he wanted. >> the officers found glove prince on the outside of the car, in the dark, on the door handles. >> so the killer came to do business. >> oh, yeah. >> when "dateline" continues. nues we're carvana, the company who invented car vending machines and buying a car 100% online. now we've created a brand-new way for you to sell your car. whether it's a year old or a few years old. we wanna buy your car. so go to carvana and enter your license plate answer a few questions. and our techno wizardry calculates your car's value and gives you a real offer in seconds. when you're ready, we'll come to you, pay you on the spot and pick up your car, that's it. so ditch the old way of selling your car, and say hello to the new way at carvana. get ready. it's time for the savings event of the year. the homeandautobundle xtravafestasaveathon! at this homeandautobundle xtravafestasaveathon, there's no telling what we might bundle! homeandautobundle xtravafestasaveathon! bundle cars, trucks, colonials, bungalows, and that weird hut your uncle lives in. so strike up the homeandautobundle xtravafestasaveathon band for the deal that started forever ago and will probably never end. homeandautobundle xtravafestasaveathon. -say it with me. -homeandautobundle-- no one's leaving till you say it right. homeandauto... the new sensodyne repair and protect with deep repair has the science to showit right. that the toothpaste goes deep inside the exposed dentin to help repair sensitive teeth. my patients are able to have that quality of life back. i recommend sensodyne repair and protect with deep repair. >> on a dark, high school we do it every night. do it. run your dishwasher with cascade platinum to save water & energy. certified dishwashers use less than 4 gallons of water per cycle. and you can also save up to $130 dollars per year on your energy bill. cascade platinum morning, cedar rapids robin detectives were called to the mall parking lot to begin a murder investigation. the body of michelle martinko and her black dress and for cool with slumped halfway off the passenger seat at the families buick electra. >> she had multiple stab wounds. >> doug larsson was a college freshman when michel was killed. matt denlinger only in kindergarten. but years later, as cedar rapids investigators, they'd come to know every detail of this case. >> very frenzied to attack. there was blood everywhere. there was blood spatter all over the inside of the car. >> did the color leave a blood trail away from the scene? did you get lucky in that? we >> know. there's no luxurious away from the scene. for that killer did leave some signatures. the officers found love prince on the outside of the car, in the dirt, on the door handle. they love looked like dishwashing gloves from the late seventies, early eighties, that everyone would have in their house. >> so, the killer came to do business? >> oh, yeah. >> the color came to do business. >> michel had warily deep defense of wounds on her hands. she put up a fight. >> the blood told them the struggle to place mostly on the passenger side. but -- >> that gearshift has blood on it. steering wheel has blood on it. we know michelle is not driving the car. >> so what does that suggest you? what is the connect the dots there? >> well the connect the dots thought that doug and i both had is the colors touching these things after he's murdered michelle. >> they thought that killer might have cut himself during the attack, leaving his own blood behind. but linking that led to a suspect in 1979, almost impossible. >> back then, they didn't have the dna analysis to go by. they used blood typing. type a blood or type the blood. which doesn't really narrow it down very much. >> still, police collected the blood for analysis. there wasn't much else at the scene to point to a who or white behind the killing. >> there was no obvious signs of a sexual assault. we really didn't have a good foundation for deciding what the motive was at that time. >> that left investigators back in the day, hanging. >> this almost like this is the heartland of the country and no place is safe anymore. >> we got the call about 6:00 in the morning, maybe 5:00 in the morning. >> gentle stone breaker, michel sister, says her parents broke the awful news to her. through subs and pleas to her. >> they were just devastated. >> even then, she sensed her parents might never recover, given how hard they had willed michelle, their second unless child, into this world. >> this is my mother and father 's miracle baby. you know? she's the child that they had tried to have for all those years. >> a child who grew up in 19 sixties and seventies, midwest america. hanging out at the roller rink, going to the lake. in middle school, a back brace for school eoc, turned her into a shy preteen. but by high school, she had done a one 80. >> when she got her brace off, that's when she just blossomed. >> gayle dawson and mike went the same halls with michelle. three close high school friends. >> all the time that she spent not wanting to be noticed, then she spent to be notice. you know? if that's when that here changed and she got into her fashion, her style. >> the pharaoh here do worked for michelle. and she intern worked. >> she was a head turner? >> she was ahead turner. there is no way you cannot notice her. >> because she had gone through that more difficult period in june or high school, i think she knew what it was like to be on the other side of that, and she would go out of her way to be kind to everyone. >> oh, yeah. >> that makes a beauty and sweetness made my, a year head of her school, fall for michelle. >> how serious wary? >> well, i was really serious. it was my first girlfriend. you know? was it the most serious relationship i had ever had. >> but it ended when he went to college. michelle had plenty of admirers though. she dated and had broken up with a guy named andy. her friends felt this andy had a hard time letting go. which may have prompted this exchange. >> she was a little bit weepy in class that one day when i asked her what was happening. what's going on? her response was that she is just tired of belonging to somebody. >> by her senior year, michelle was focused on college. >> she definitely conveyed to me she was ready to put high school and cedar rapids behind her. >> for thomas, the voice you hung out with the night she was murdered, a certain michel was preparing to leave the building when they said their goodbyes. >> you don't think that person is going to walk out the door and you're never going to see them again. >> kurt says he still feels guilty about how he handled that goodbye. >> i could've walked or to the car. i could've done something. >> we're standing where her vehicle was found. >> now more than 40 years later, the encounter of michel's final steps to her car is mostly guesswork. >> just around the other side of jcpenney would've been the public entrance that she exited from. >> i think she's got a long walk in the call to get your vehicle. >> yeah, it's a long. walk >> a good hundred yards or so. >> it's mid december, it's dark, the law is probably not real well like in 1979. yeah, she's got a long walk. >> a long walk through a dark lot. now, at least for eager to speak to one of the last friends known to have seen michelle martinko a life. >> coming up -- >> the principal turned and said, mr. thomas, we need to talk to you. okay. >> a possible suspect. >> it was just like they do it on tv. this guy leaned over and said, why did you kill her? talk about there in the headlights looking kid. >> and an ugly rumor. >> the theories were just awful. i mean, it when everything from drug rings to prostitutes brings. >> when "dateline" continues. "dateline" continues in business, it's never just another day. it's the big sale, or the big presentation. the day where everything goes right. or the one where nothing does. with comcast business you get the network that can deliver gig speeds to the most businesses and advanced cybersecurity to protect every device on it— all backed by a dedicated team, 24/7. every day in business is a big day. we'll keep you ready for what's next. >> even now, decades later, comcast business powering possibilities. kurt thomas remembers the moment that morning at school, principal showing up in his classroom and looking straight at him. trouble. >> the principal turned and said, mr. thomas, we need to talk to you. okay. and i get up and when i walk there he said, i need you to go out in the hallway and talk to these gentlemen. >> these gentlemen were the two detectives forced the sign to the case. kerr says he didn't know why they'd wanted to talk to him, because he hadn't heard about the murder yet. soon, he was inside an interrogation room, answering questions about the previous day. >> go through the night, kurt. what time did you get a school? did you drive from schools? you know? >> they want to timeline. >> very factual. >> he says after hours of back and forth, the detectives finally told him michel had been murdered. the unhappy fact was you were the last person in her circle of associates not seen her life. >> that realization hit me like a brick. that's >> not a good place to be in. >> oh, no. at that point, i was somewhere in shock. >> then he says, they hit him with it. >> and it was just like the do it on tv. this guy wheeled around and put his hands on the desk and leaned over and said, why did you kill her? >> now is the time to give it up and do yourself some good. >> oh, talk about there in the headlights looking kid. >> but then his store manager for the white mall was on the line. she told detectives kurt had gone on break, return to the store at around 9:30, and helped her close up shop about ten. police believed michelle left them all sometime in that half hour. >> this detective said mr. thomas, you can go. i didn't know what that meant. as stupid as that is to say, can i really go? >> for the moment, at least, kurt was in the clear. in fact, michelle brother-in-law's, john, already had someone else in mind for her murder. old boyfriend andy. he was >> he was very possessive after they broke up. he parked down the street sections when it was someone else. he drive fast around the block. so, i was pretty sure it was andy. if i can't have her, nobody can have her type of thing. >> sure enough, andy was brought in for questioning. matt denlinger and doug harrison understood why the first detectives took a hard look andy. >> and he was at the mall that. nick >> watt was historic? why did he see was there? >> he was there to buy her christmas present. >> her? his ex girlfriend? >> yeah. >> the night she's killed, he's at the mall to buy her if president, even though there are no longer boyfriend, girlfriend. >> correct. >> i mean, that sounds cute curious even out, just saying it. >> because a lot of the detectives thought that might be too much of a coincidence. >> and he recounted his movements for detectives. he and a budding bumped into michelle at the moment around 8:30. he said he had no idea michelle was missing until her father called his house about 3:30 am. he told detectives he and his mom jumped in the car to go searching. but couldn't find her. so, was the early thinking we're going to get this young guy and he and have a case here? >> i think so. yes >> kind of sweat him a little bit, and he'll come. >> yeah. >> the andes story never changed. and police had no physical evidence to connect him to the murder. and without a quick arrest, the cedar rapids gossip mill started churning. it as time slip by, people became suspicious of michelle, herself. >> the theories were just awful. i mean, it went everything from drug rings to prostitution rings. >> that somehow this young girl brought it on herself, right? >> absolutely. because surely, she had to be involved in this. >> painful for your parents? >> horrible. my mother eventually did not go out of the house. she just stayed at home. >> michelle's death and the failure to find her killer, also had a profound effect on the city where she had lived. >> people were really upset and traumatized by it. >> trish is the court reporter for the cedar rapids paper the gazette. second >> back in 1979, cedar rapids was smaller than it is even now. it was a close knit community. >> cedar rapids in those days was very may very like. and honestly, what happened to michelle kind of stripped away, not just our innocence that the innocence of the whole town. >> it settled over the city. the thought that michelle's killer might never be caught. the seventies became the eighties, and then the nineties. the dawn of dna testing finally gave police new hope. in 1997, they sent scrapings from that gearshift of michelle 's car off to a state lab. >> the lab was able to sort out all of those dna points and left a partial meal the any profile. >> at the time, it was an enough to match to a suspect. but in 2005, doug larsson took over the case. he wondered if anything else from the car might yield a more complete dna profile. he sent michelle's blood stained dress back to the state crime lab. >> got the phone call from the lab analysts that they had found a full dna profile on the dress, which was very exciting. >> that's a pretty exciting phone call? >> that's great. all we had to do with submit the profile to codis -- >> codis? it's >> an fbi computerized systems that come teens millions of profiles that have been collected from crime scenes, from jails, people who have been arrested. >> and anything come back? >> nothing. no hit. >> to larsson, that meant michelle's killer was likely someone about any prior arrest or run-ins with a lot. that meant compute people police police had talked back in the day had to be reconsidered. >> my thinking is, let's start going through this case. let's start finding potential suspects. and the school get their dna and start eliminating them from that partial profile. >> so, now are we back to andy and all those other boyfriends? >> correct. >> nearly 30 years after michelle the's death, everything old was new again. boys with alibis back in 1979, we're now middle aged men with something more valuable than a story to offer. they had there dna. >> coming up -- >> you're going to take a molecule of human genetic material and turn it into an image of some kind? >> correct. >> using dna to paint a portrait of a color and trees his family tree. >> so you've got a lot live on at the bottom of this tree. >> we've got live one here, only 20 minutes away. >> what do you think at that moment? >> we're ecstatic. >> you can taste it at that point. we're ready to go. >> when "dateline" continues. instantly ready to start working. so you can bounce back fast with alka-seltzer plus. that's a nice truck. yeah, it's the chevy silverado. check out this multi-flex tailgate. multi-flex, huh? wow. it becomes a step. mom, dad's flexing again. that's not all. you can extend the bed for longer stuff. is he still... still flexing. that's right! and, it becomes a workspace... you can put your laptop here. i'm sending an imaginay email. hey dad, dinner! hey! look who stopped by daddy's office. wait, you work here? the chevy silverado with the available multi-flex tailgate. find new flexibility. find new roads. chevrolet. with voltaren arthritis pain gel my husband's got his moves back. find new flexibility. find new roads. an alternative to pain pills voltaren is the first full prescription strength gel for powerful arthritis pain relief... voltaren the joy of movement we did it again. verizon has been named america's most reliable network by rootmetrics. and our customers rated us #1 for network quality in america according to j.d. power. number one in reliability, 16 times in a row. most awarded for network quality, 27 times in a row. proving once again that nobody builds networks like verizon. that's why we're building 5g right, that's why there's only one best network. clerk: hello, how can i? sore throat pain? ♪honey lemon♪ try vicks vapocool drops. in honey lemon chill. for fast-acting sore throat relief. wooo vaporize sore throat pain with vicks vapocool drops. ♪ i see trees of green ♪ ♪ red roses too ♪ ♪ i see them bloom for me and you ♪ (music) ♪ so i think to myself ♪ ♪ oh what a wonderful world ♪ >> i'm dara brown. here's what's happening. the federal judge is temporarily -- forcing a vaccine mandate for teachers and other workers. this mandate for the nation's largest school system was originally set to go into effect on monday. and also monday, house democrats will had the at 5:30 pm to discuss the next steps for the bill. this comes after a house budget committee approved the 3.5 trillion dollar reconciliation package during a rare saturday session. now back to "dateline". >>session. >> welcome back to "dateline". i'm craig melvin. michelle martinko's unsold murder marked a loss of innocence for her friends and family. but not a loss of hope. cold case detectives were determined to catch the killer using a modern arsenal of tools. the same technology used to crack a legendary case in california, was about to reveal a tantalizing clue. back to dennis murphy with "and then there were three". >> the decades old investigation into michelle martinko's 1979 murder had emergency. detective doug larsson had a dna profile of the killer and the traditional list of suspects. one by one, he started asking for dna samples, looking for a match. >> doug started with the really obvious suspects. all the ex-boyfriends. kurt thomas, old high school buddies that had been at the mall. >> at the top of that list was ex-boyfriend andy. >> i thought it was just a matter of time before andy was found to be a killer. >> that andy's dna was not a match. more than 25 years after he was first considered a suspect, he was cleared. justice for andy -- >> nothing to do with it. he had to live with that cloud over him because so many people did think he was involved. >> kurt thomas, the last person in her circle known to a scene michelle at the mouth, was also tested. police called his lawyer with the result. >> they got him on the phone and said, the dna is not a match, and they hung up. but >> the headline was, the dnc says it's not you. >> right, right. >> another possible suspect cleared. another setback for the cedar rapids police department. but when matt denlinger took over as lead investigator in 2015, he still thought dna would solve the crime. so, he did another deep dive into a case file that had been built by so many before him. >> now, we're just trying to find men who were listed in these reports, that could have possibly had a connection to her, or men that would've had a connection to the mall. i thought eventually, if we come enough people, we're gonna get our suspect. >> that after more than 125 tests, no one matched the killers d.o.t.. they were out of leads. and then parabon comes into this. what is that? >> parabon is a private lab. what parabon was offering is to take the genetic profile that we had and to create an image. >> create an image? >> yeah like an actual -- a >> me like an up in the office photo to be on the lookout for this guy? >> exactly, a computer generated, philly sketch. >> excuse me i sent a little skeptical. that sounds like food science fiction. [laughs] you're gonna take a molecule of human genetic material and turning into an image of somebody? >> correct. >> three catches were greeted from the dna profile. the suspected killer imagine that is 25, another age 50, and one with a typical 1979 here cut. police released the pictures to the public. >> we were hoping that 100 people would call in and say, that looks like person a. the problem is, we got 250 people call in and see it looks like 100 people. >> oh, man. more needles, more hair stacks. >> yeah, a lot of rabbit holes we went down. i tracked down another 50 people and swapped them. each time, hoping that this would finally get our guy. >> but with each dna test result, that hope was dashed. that, in 2018, parabon helped solve the golden state killer case, using new technology called genetic genealogy. >> again email from parabon saying hey, check out what we just did. >> parabon offered a similar genealogy search for the martinko case. using their dna from the crime scene, they would try to identify relatives of the killer, by searching through genetic profiles on an online database. denlinger give them the green. like >> we said that in the spring of 2018, and by the summer, they had sent us report. and they said, that they had found the relative of our killer. >> a relative of your color? >> yeah. they hypothesized that she was a second cousin, what's removed, from our color. >> well there's a headline for you guys. >> yeah. >> that person related to the killer was a woman living in vancouver, washington. now the trick was to build a family tree to see if police could link a family member to cedar rapids in 1979. denlinger reached out to the woman, she agreed to answer all his questions. >> we have to start building her family tree. >> denlinger trace the woman's family treat back to the early 18 hundreds. >> so, you're looking through all historical records, census data -- >> absolutely. >> tombstones? >> tombstones. anything we can find. >> created four branches of the family, going back to great, great grandparents. the first branch lead to someone living in ohio. denlinger got a dna sample. >> we sent their dna back to parabon, and they recalibrated and told us that we can eliminate that branch of the family tree. >> don't waste your time on that tree. >> do we certainly. that that person shares no dna with your color. this one here, we wonder in nebraska. and said that one in. same thing. boom. get rid of that one. we don't need to worry about that branch of the family tree. >> on the next branch, denlinger found a relative living in iowa. so, you got a live one here at the bottom of the street? >> we've got lies one here. this was a gal in lisbon, iowa, she's only 20 minutes where. >> she's not your color of course? >> definitely not the color. we all see the color was a man. we took a dna and sent it to parabon. boom. she shares enough with that color to be a first cousin. >> it turns out the woman sheer dna with three first cousins. three brothers. after four decades and so many disappointments, a suspect list had narrowed to three. >> all three of them are still alive, still living in iowa. >> what do you think at that moment? >> we are ecstatic. you can taste it at that point. we're ready to go. >> detectives are about to get up close and personal with the three brothers, without them knowing it. coming up -- >> and he and his son leave, we grab the cup off his table. my partner put some gloves on, grabs the straw, the glass, packages it up. and we disappear. >> then, not a confession, but not eternal, either. >> what happened that night? >> did you murder that night someone that night, jerry? 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(vo) buy your next car 100% online. with carvana. ♪ ♪ ♪ ♪ ♪ ♪ >> and then there were three. after chasing down hundreds of leads over four decades, that suspect less in michelle martinko's murder had narrowed down to three brothers living in iowa. when you run the computer check. criminal records? anything come? up >> no. >> so they're leading respectable middle class lives as far as you can see. >> yeah, very much. >> the family name was burns and all three brothers were adults in 1979. but did not seem to have any connection to michelle martinko. investigator math denlinger and two colleagues decided to secretly connect dna from all three. so, this is when you become a double agent. it's really shifting gears here? >> it is shifting gears. >> they track the brothers one at a time, starting with middle brother kenneth. a married father of three, he sold from equipment in manchester, iowa. about a 50-minute drive from cedar rapids. >> the collected his dna from a straw and it immediately goes to the state lab. they told us, hey, he is not your suspect. the next brother was donald. >> this brother donald, was a father of three and had five grandchildren. he lived in davenport, iowa, and was the manager of a lumber yards before retiring. went denlinger to his house and staked it out surreptitiously. >> the first time we corrected was out of the trash by the set by the curb. we found a toothbrush in there and collected some dna off of that. >> and what did the lab think about his genetic material? they >> said the same thing. >> he's not your guy? >> he's not your guy. >> it came down to the youngest brother, jerry burns, who like brother can't, worked lived and worked in manchester. denlinger did some intel on him. >> in 1979 he had two young kids. he lived in manchester. he sold farm implements. was in a bowling lead. >> so, these married with children, 9 to 5 guy? >> yeah. >> on an october morning in 2018, denlinger and his team set out for manchester in three unmarked cars. so jerry's places right out here? >> it's in seconds is going to come up on us, in no. time >> police followed him throughout the morning. finally, at lunchtime and opportunity. burns and his son had pulled into the pizza ranch restaurant. >> he parked in the parking lot there and he went in and i was sitting at a booth right by the window there. >> denlinger and his partners went in and signed a. both you're in the next move over? >> and then closer him as you and i are right now. >> you've got to be thinking, this is my color? >> yeah, it's hard to enjoy your food when you think you're staring at the color. >> burns was drinking a soda from a straw. denlinger didn't take his ivs off of it, making sure nobody else touched it. >> then he and his son leave, they drive away from the pizza ranch. we grab the cup off the table. my partner put some gloves on, grabs the straw and the glass, package it up, and we disappear. >> the sample was sent for testing. it was the moment of truth. jerry was not one of the last burns brother, he was the last possible suspect. denlinger we'll never forget the moment he spoke to his contact at the crime lab. >> he says, that's your guy. >> he's the color? >> he's the killer. >> the lab reported that the scientific probability was 100 billion to one. that meant the dna from the crime scene belonged to jerry burns and not anyone else on earth. finally, it was the culmination of relentless decades long investigation. but denlinger was it ready to make an arrest. there were just too many questions that needed answers. >> it's time to go talk to him. he's not going to be ready. which is the best time to try to interview someone. >> so, on december 19th, 2018, denlinger headed back to manchester. he pulled up to burns a's place of business a little before noon. the door was open. denlinger walked in. a hidden camera recorded everything. >> hello. >> you have backup? >> a lot of backup. we had no good expectation or what to expect from him. what to expect from his behavior. >> what's in his desk or? >> yeah. correct. >>'s camera was hidden in a travel mug. he introduced himself and set the mug down on burns's desk. >> he sits there and he's putting the shop cat, who's climbing all over the duster in the interview. >> we've got cat here, ha? >> what's the cat's name? >> no. >> denlinger and it burns a business card and then got down to business. >> we're following up on an old case. it's a homicide that happened in westdale mall. then he described the computer sketch released to the public that was developed from dna found at the crime scene. he said someone called in with a chip and that's how burns's came up. that wasn't true. but denlinger wanted to see how he would react. >> that's the picture we created. >> it looks a lot different than i look here. i look like that? >> well, i kind of think you do a little bit. enough that we bother to come up here to talk. >> burns remained calm and polite. he denied knowing michelle it but didn't say much more. you're holding the major's card here? >> right. >> here's what science says. do you confirm with that? >> we did. we directly confronted him with. that >> we have your dna the crime scene. so, we know you were there that night this happened. how will we get your dna the crime scene there jerry? >> i don't know, tested, see if it is. >> no, we did. how would it be, there jerry? >> i don't know. >> what happened that night? >> did you murder someone that night, jerry? >> tests the. dna >> jerry. >> tests the dna. >> it wasn't the confession denlinger was hoping for, but he didn't think it was internal either. so, 39 years to the day after's murder, jerry burns was cuffed and placed under arrest. >> we have the right to remain silent. anything you can say cannot will be used against in the court of law. >> the church was first degree murder. for jury burns's daughter and his brother, the news was a gut punch in. possible to comprehend. >> it almost seems like a dream. that it was it really happening. it was really true. >> could you believe it? >> no. >> my brother had said dad's been arrested for murder. just like, who -- i was so in disbelief. >> the arrest just didn't square with the image of the devoted father, the good kid brother that they could always known. they felt certain there was something wrong with that dna evidence. >> there's lots of other stories out there where there's a mistake of dna found at crime scenes. and there's an explanation for why it's their. does it mean that whoever's dna it was is that person that committed the crime? >> there's nothing to substantiate when it came there, how it got their. >> today, now you see this just cannot be right. >> no, they can't be right. >> jerry burns's family was convinced he was instant. could prosecutors convince her journey he was the killer? >> coming up -- a damning discovery. >> there were files found on mr. burns computer. >> extreme pornography? fair to say? >> i think it was described publicly as deviant pornography, violent pornography. >> and the risk of relying on dna evidence. >> i taught fifth grade. i know how hard it is to teach somebody something. you have to repeat over and over again. i'm concerned about that. >> when "dateline" continues. now how i feel ♪ [man: coughing] ♪ it's a new dawn, it's a new day... ♪ no matter how you got copd it's time to make a stand. ♪ ...and i'm feelin' good ♪ start a new day with trelegy. no once-daily copd medicine has the power to treat copd in as many ways as trelegy. with three medicines in one inhaler, trelegy helps people breathe easier and improves lung function. it also helps prevent future flare-ups. trelegy won't replace a rescue inhaler for sudden breathing problems. tell your doctor if you have a heart condition or high blood pressure before taking it. do not take trelegy more than prescribed. trelegy may increase your risk of thrush, pneumonia, and osteoporosis. call your doctor if worsened breathing, chest pain, mouth or tongue swelling, problems urinating, vision changes, or eye pain occur. it's time to start a new day. ask your doctor about once-daily trelegy. and save at trelegy.com. we do it every night. ask your doctor about once-daily trelegy. do it. run your dishwasher with cascade platinum to save water & energy. certified dishwashers use less than 4 gallons of water per cycle. and you can also save up to $130 dollars per year on your energy bill. cascade platinum ♪ when you hear 'cough cough sneeze sneeze' ♪ it's time for ♪ 'plop plop fizz fizz' ♪ alka seltzer plus cold relief, dissolves quickly... instantly ready to start working. so you can bounce back fast with alka-seltzer plus. 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's sister janel and her husband john, traveled from their florida home to attend. determined to see it through to the. and every day. >> every day, if the jury has to be there, will be. there >> you examined the dress -- the >> prosecution put detective dug larison on the stand to tell jurors the police found followed sound practices when they handled's clothing. >> we wore rubber gloves, for one. thankfully tried not to disturb the clothing items. just to get a quick look at them and re-insert them back into their original packaging. >> dna analysts, linda, since retired, testified the dna collected from that evidence could only be long to one person. >> the probability of finding two unrelated and officials is so small, that they can be discounted. >> the defense attorney spies was rolling over for the state's dna case. >> jerry lynn burns is not guilty of the killing of michelle martinko. >> the defense attorney went after the cops for the way they handled the evidence over four decades. spies argued key items like michelle's dress were jumbled up with her other clothing, containing them forever. >> when you opened up the original packaging of the dress, the panties and the pantyhose, where the items all bundled together? >> as far as i recollect, they were, yes. >> and there was another reason to question the prosecutions, the defense attorney said. something called dna transfer. he quizzed his own expert witness. >> is it, doctor spends, a plausible explanation that the dna of jerry burns, out on the dress or on that gear shift, could have come about by a transfer? >> yes, that's a distinct possibility. >> the defenses dna expert told the court might burns have left his dna at the mall innocently, on a door, on the bench. after all, he told investigators that he had visited them. all >> janice burns's danny -- >> jerry burns the defense argued, was a victim of coincidence and sloppy defense work. >> ladies and gentlemen, the evidence has been submitted to you. >> after eight days of testimony, their jury got the case. when it goes out to the jury what do you think? >> i mean, we are hoping for the best. if he wasn't guilty, great, we have might at home. if he was guilty, it just meant more work. we're fighting for him. >> gentle was worried for a different reason. she knew that prosecution's case, that dna testing, the genetic genealogy was complicated. dense data. >> i taught fifth grade. i know how hard it is to teach somebody something. you have to repeat it over and over and over again. i'm concerned about that. >> thank you. >> as it turned out, the jury reached a quick verdict. judge hoover read the decision allowed. >> we, the jury, find the defendant jerry lynn burns guilty of the charge of murder in the first degree. >> how did he take it, the verdict? >> i think he was shocked, to. he was very much expecting to come home. >> don, you're in court for the verdict? >> i was surprised at the verdict. i had a hard time believing that the jury sat down and even reviewed the case. >> three hours? >> yeah. >> not even three. >> i couldn't believe they came back with a verdict they did. >> outside the courthouse, john and janel were emotional. >> to finally have the closure on this and to actually no -- i wish my parents could be here to see this. >> we left cedar rapids -- but cedar rapids never left us. >> i could feel the pressure of 40 years and countless police officers that have worked on this case. i felt like we as a team had finally done justice for the martinko family. >> jerry burns was sentenced to life without parole. he is appealing his conviction. >> as we were looking through pictures, we realized that she wasn't part of that christmas. she wasn't part of that birth. she was part of that party. we kept going deeper and deeper into the box, trying to find where was michelle? she had missed everything. >> the family album goes on, but she's not in. >> she's not in it. >> no, she's only in the old photos. a girl smiling out into a world of possibilities. stolen, on a cold, december night. >> that's all for this edition of "dateline". i'm craig melvin. thank you for watching. for watching i'm natalie morales, and this is dateline. >> red cauldron calls 9-1-1 and says his wife appears dead. >> he said that he had found her in the bathtub. >> i have never seen my son shell-shocked. >> it was a case tailor-made with the tabloids. >> we had this beautiful woman, a tall handsome guy, breed, infidelity. >> he is out with other women. >> a failing marriage with millions at stake. >> he didn't have