blood spatter inside the car. it was a frenzied attack. >> the theories were awful. drug -- drug rings, prostitution rings. >> the town was going crazy. are going to come across the suspect. >> it was fascinating how they went about the investigation. >> we got a call and there's three brothers and we think one is a killer. >> we've got a live one here. >> what do you think? >> we are ecstatic. he was sitting at a booth by the window. it's hard to enjoy your food when you think you are staring at the killer. >> hello, welcome to dateline. teenager michelle martinko was blessed with beauty, brains, and compassion. 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 whittle down a list of suspects to unmask a killer hiding in plain sight. here is dennis murphy with and to then there were three. >> it was an act of unspeakable violence. >> it was a horrific crime. everybody was scared. >> a murder that shattered a family. >> my parents were devastated. my mother eventually did not go out of the house. >> a whodunit that grabbed hold of a city and would not let go. >> a dark cloud hanging over the community. >> a case that touched generations of investigators who refused to quit until the killer was found. >> that cared about the family. they cared about the murder. they were not going to give up and they did not. >> he said he was a lucky kid. he got to grow up in cedar rapids, iowa. >> it was a magical bubble. we did not know anything but fun. >> a lot of the fun happened at the mall. for teenagers it was a place to shop, eat, and hang out. that's where the kids hung out? >> you could go any time and it was a big deal. >> high school senior michelle martinko shopped and worked at a mall near her home. michelle was a top student, gifted baton twirler and sang in the school choir along with her friend jane. why do you think you hit it off as well as you did? >> we had a lot of things in our life that was parallel. >> what she girly girl or a tomboy? >> she was a girly girl. >> december 19, 1979 was a big night for michelle. it was her christmas banquet at the sheraton with her hair done to perfection and decked out in her favorite black dress and rabbit fur coat, she look like and angel. a charlie's angel. john is her brother-in-law. >> farrah fawcett majors time. with the hair. she was farrah. >> it was a school night, after the banquet, michelle asked jane to go with her to the mall but jane had homework to do. michelle said let's go to the mall tonight, that was not going to work for you? >> correct. i turned her down. >> shell got in her parents buick electra and headed to the new west dale mall on the southwest side of town. she had $180 cash on her to pay for coat her mother picked out. kurt was also at the mall that night working a shift at the men's store. >> saw this beautiful girl in a rabbit fur coat, black dress, high-heeled shoes. blonde hair. then i was like, that is michelle. >> they were friends from school. she joined him for a break and they went for a stroll. at one point passing by a girl he had a crush on. >> it pops in my head, i'm never going to get to dance with that girl. >> i have miss america on my arms. >> he said he and michelle spent their break catching up until he had to get back to work. spent that's when we are seeing good-bye. she said don't be a stranger. >> did you think you would see her again? >> of course i did. >> it was not a night to stay out late so when michelle had not returned home even after the mall had closed, her sister said their mother started to worry. >> my parents started calling to see whether other friends with the situation was. >> why is she not a home? >> janet did call the police as well. they said we can look after every teenager who is missing for a couple of hours. janet resisted and said she's very dependable and she should be home. she has a test tomorrow and she has to study. >> her mom kept making calls late in the night. 2:30 a.m., she dialed michelle's friend jane. >> i was sound asleep. my dad came and woke me up. said she wanted to know if i knew where michelle was. >> jane didn't know. nobody did. in the middle of the night in a panic, michelle's mom called the police again. this time they dispatched an officer. jim kincaid got the call at 4:00 a.m. >> they sent me to the mall to see if i could locate this car. >> the mall was bustling with christmas showers hours earlier and now it was dark and deserted. in the distance, the officer spotted a car in the far reaches of the parking lot. a long walk from the entrance to the jc penney. >> is seem to match the description of the one i was sent to find. >> looking from your vehicle, could you see what happened? >> no. >> couldn't see in the windows? >> i open the back door and i could see there was a woman slouched down. at first i thought it was an intoxicated person. i walked around the car and looked in the front window of the passenger side and it was not an old woman drunk. >> could you tell she was gone? >> there was no signs of life. it was obvious she was deceased. >> beautiful vivacious high school senior michelle martinko was dead. she was just 18 years old. for her family and close friends, the christmas season and life as they knew it ended that night, and the new west dale mall had become a crime scene. >> coming up. what had happened to michelle? >> frenzied attack. there was blood everywhere. blood spatter inside the car. >> she had defensive wounds on her hand's. her hand's. oh, yeah. craig melvin: when dateline continues. choose advil liqui-gels for faster, stronger and longer-lasting relief than tylenol rapid release gels because advil targets pain at the source of inflammation. so for faster pain relief, advil the pain away. 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[coughing] copd hasn't been pretty. it's tough to breathe and tough to keep wondering if this is as good as it gets. but trelegy has shown me that there's still beauty and breath to be had. because with three medicines in one inhaler, trelegy keeps my airways open and prevents future flare-ups. and with one dose a day, trelegy improves lung function so i can breathe more freely all day and night. 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. ♪ what a wonderful world ♪ ask your doctor about once-daily trelegy for copd because breathing should be beautiful. [♪♪] your skin is ever-changing, take care of it with gold bond's age renew formulations of 7 moisturizers and 3 vitamins. for all your skins, gold bond. introducing new advil targeted relief. the only topical pain reliever with 4 powerful pain-fighting ingredients that start working on contact to target tough pain at the source. for up to 8 hours of powerful relief. new advil targeted relief. for up to 8 hours of powerful relief. dennis murphy: on a dark, ice cold morning, cedar rapids detectives were called to the mall parking lot to begin a murder investigation. on a dark, ice cold morning, cedar rapids detectives were called to the parking lot to begin a murder investigation. the body of michelle martinko in her black dress and for coat was slumped hefley off the passenger seat of the family's buick electra. >> she had multiple stab wounds. >> dog was a college freshman when she was killed. matt only in kindergarten. years later as cedar rapids police investigators, they would come to know every detail of the case. >> a frenzied attack. there was blood everywhere and blood spatter over the inside of the car. >> did the killer leave a blood trail away from the scene? >> no. the killer did leave some signatures. the officers found glove prints in the dirt, on the door handle. they looked like dishwashing gloves from the late 70s that everyone would have in their house. >> the killer came to do business. >> oh, yeah. michelle had deep defensive wounds on her hands. she put up a fight. >> the blood told them the struggle took place mostly on the passenger side, but -- >> the gearshift as blood, we know michelle is not driving the car. >> what does that suggest? >> the thought we had is the killer is touching these things after he has murdered michelle. >> that thought the killer might've cut himself during the attack, leaving his own blood behind. linking the blood to a suspect in 1979, almost impossible. >> back then they did not have dna analysis. they used blood typing, type a or type b blood which doesn't narrow down very much. >> police collected the blood for analysis. the wasn't much else at the scene 2.2 who or why behind the killer. >> there is no obvious signs of a sexual assault. we did not have a good foundation for deciding what the motive was. >> that left investigators hanging. >> it's almost like this is the heartland of the country and no place is safe anymore. >> we got the call about 6:00 a.m. in the morning. >> janel, michelle's sister said the parents broke the awful news to her through sops to hurry home. >> they were devastated. >> she sensed her parents might never recover given how hard they had world michelle their second and last child into this world. >> this is my mother and father's miracle baby. the child they had tried to have for all those years. >> a child who grew up in the 1960s and 1970s in midwest america. going to the lake. in middle school, a back brace for scoliosis turned her into a shy preteen but by high school she did a 180. >> when she got her brace off, that's when she blossomed. >> they were on the same house with michelle. three close high school friends. >> all the time she spent not wanting to be noticed and she spent to be noticed. that is when the hair changed and she got into fashion and style. >> the here do work for her and she worked it. she was a head turner? >> she was a head turner. >> because she went through that more difficult time in high school, i think she knew what it was like to be on the other side of that. she would go out of her way to be kind to everybody. >> that mix of beauty and sweetness meet mike fall for michelle. how serious were you with her? >> i was really serious. it was my first girlfriend. the most serious relationship i had had. >> it ended when he went to college and michelle had india admirers. she dated and broken up with a guy named andy. her friends thought he had a hard time letting go which may have prompted this exchange. >> she was a little weepy in class and when i asked her what is going on? her responses she is tired of belonging to somebody. >> michelle was focused on college. >> she conveyed to me she was ready to put high school and cedar rapids behind her. >> kurt, then why she hung out with the night she was murdered, she was prepared to leave the building when they said their goodbyes. >> you don't think that person will walk out and you will never see them again. >> he said he feels guilty about how he handled that good- bye. >> i could have walked her to the car. i could've done something. >> we are standing where her vehicle was found. >> more than 40 years later, the count of her final steps to her car is mostly guesswork. >> just around the other side would've been the public entrance she exited from. >> she has a long walk to get to her vehicle. a good 100 yards. >> it's december. it start. the lot was probably not well lit. she's got a long walk. >> a long walk through a dark lot and police were eager to speak to one of the last friends known to see michelle martinko alive. >> the principal turned and said mr. thomas, need to talk to your. okay. >> a possible suspect. >> it was like they do it on tv. this guy leaned over and said why did you kill her? talk about deer in the headlights look. >> an ugly rumor. >> the theories were awful. drug rings to prostitute rings. dennis murphy: even now, decades later, curt thomas remembers the moment, that morning at school, the principal showing up in his classroom, and looking straight at him, trouble. even now, decades later, kurt thomas remembers ipalthe moment. that morning at school with the principal showing up and looking straight at him. >> the principal turned and said mr. thomas, need to talk to you. okay. i get up and when i walked there, he said, i need you to go in the hallway and talk to these gentlemen. >> they were the two detectives first assigned to the case. kurt said he didn't know what they wanted to talk to him because he had not heard about the murder yet. soon he was inside an interrogation room answering questions about the previous day. >> go through the night. what time did you get off school? they were very factual. >> after hours of back and forth, the detectives finally told him michelle had been murdered. the unhappy fact is you were the last person to have seen her alive. >> that realization hit me like a brick. >> that's not a good place to be. >> oh, no. i was somewhere in shock. >> then they hit him with it. >> just like they do it on tv. this guy put his hands on the desk and leaned over and said, why did you kill her? >> now was the time to give it up and do yourself some good. >> talk about the deer in the head like look. >> then his store manager was on the line. she said curt had gone on break and returned it 8:30 and helped her close up shop around 10:00 police believe michelle left the mall and 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, he was in the clear. former first lady michelle obama john already has someone else in mind for her murder. her old boyfriend andy. >> he was very possessive. he would park down the street to see if he was seeing someone else. i was pretty sure it was andy. if i can't have her nobody can. >> he was brought in for questioning. they understood why the first detectives had taken a hard look at andy. >> he was at the mall that night. >> he was there to buy her a christmas present. >> his ex-girlfriend? >> yeah. >> the night she's killed he's there to buy her a present even though there no longer boyfriend and girlfriend? >> correct. >> that sounds curious even now. >> a lot of detectives thought it was too much of a coincidence. >> he recounted his movements. he and a buddy bumped into michelle around 8:30. he said he had no idea michelle was missing until her mother called his house about 3:30 a.m. he told detectives he and his mom jumped in the car to go searching but could not find her. was the early thinking we will get this young guy and he and solve the case? >> i think so. >> andy's story never changed and police had no physical evidence to connect him to the murder. without a quick arrest, the cedar rapids gossip mill started churning. as time slipped by, people became suspicious of michelle herself. >> the theories were awful. from drug rings to prostitute rings. >> somehow this young girl brought it on herself? >> she had to be at fault in this. >> painful for your parents. >> horrible. my mother eventually did not go out of the house. she stayed at home. >> michelle's death and the failure to find her killer also had a profound effect on the city where she lived. >> people were upset and traumatized by it. >> trish is the court reporter for the cedar rapids paper the gazette. >>79, cedar rapids was smaller than it is now. it was a close knit community. >> what happened to michelle kind of stripped away not just our innocence but the innocence of the whole town. >> is settled over the city. the thought michelle's killer might never be caught. the 1970s became the 1980s then the '90s. the dawn of dna testing finally gave police new hope. in 1997, they sent scrapings from the gearshift off to a lab. >> they were able to's sort out the dna. >> at the time it was not enough to match to a suspect but in 2005, doug took over the case and wondered if anything else from the car might yield a more complete dna profile. he sent michelle's bloodstained dress to the crime lab. >> got the phone call from the analyst they found default dna profile on the dress which was exciting. all we had to do was submit this profile and probably -- >> what is that? >> it contains millions of dna profiles collected from crime scenes, from jails. people who have been arrested. >> anything come back? >> no it. >> that meant michelle's killer was likely someone without prior arrests or run-ins with the law. that meant believed -- >> let's start going through the case and start finding potential suspects and let's get their dna and start eliminating them from the partial profile. >> were back to and he and the other boyfriends? >> correct. >> 30 years after her death, everything old was new again. boys with alibis in 1979 were middle-age men with something more valuable than a story to offer. they had their dna. >> coming up. >> you will take a molecule of human genetic material and turn it into an image? >> using dna to paint a portrait of a killer and trace his family tree. >> you have a live one here. >> 20 minutes away. >> what do you think? >> we are ecstatic. we are ready to go. billy: one second, grandma. this guy is going to buy my car. okay? grandma: you need carvana... entering plate number... grandma: no accidents, right? billy: no. grandma: generating offer... carvana can pick it up tomorrow! billy: that's an amazing offer. announcer: sell your car the easy way with carvana. [♪♪] your skin is ever-changing, take care of it with gold bond's age renew formulations of 7 moisturizers and 3 vitamins. for all your skins, gold bond. introducing new advil targeted relief. the only topical pain reliever with 4 powerful pain-fighting ingredients that start working on contact to target tough pain at the source. for up to 8 hours of powerful relief. new advil targeted relief. i'm richard lui. after days of flooding in florida, that state and others are bracing for an intense heat wave. the pacific northwest wills have cold weather and the potential for late-season snow in the rocky mountains next week. kate middleton, princess of wales, made her first public appearance saturday. she attended a ceremony for king charles birthday parade. her first official appearance since revealing her cancer diagnosis. michelle martinko's unsolved murder welcome back to dateline. i am craig melvin. michelle martinko's unsolve 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 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 a new urgency. the detective had a dna profile of the killer and the original list of suspects. one by one he started asking for dna samples, looking for a match. >> doug started with the obvious suspects. the ex-boyfriend's. kurt thomas, the high school buddies that had been at the mall. >> at the top of the list was ex-boyfriend andy. >> i thought it was a matter of time before andy was found to be the killer. >> but his dna was not a match. more than 25 years after he was is considered a suspect, he was cleared. justice for andy. >> he has nothing to do with it. he had to live with that cloud over him because so many did think he was involved. >> curt , the last person known to have seen her at the mall 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. >> the dna says it's not you. another possible suspect cleared. another setback for the cedar rapids pd. when matt took over as lead investigator in 2015, he still thought dna would solve the crime. he did another deep dive into a case file that had been built by so many before him. >> we are trying to find men listed in these reports that could've possibly had a connection to her arm and that would've had a connection to the mall. i thought if we swab and of people, we will come across the suspect. >> after more than 125 tests, no one match the dna. they were out of leads. >> a private lab, what they were offering is to take the genetic profile we had and create an image. >> create an image? like up in the post office photo? >> exactly. computer-generated police sketch. >> excuse me if i sound skeptical. that sounds like voodoo science. a molecule of human genetic material and turn it into an image? >> correct. >> three sketches were created. the suspect a killer at 25, another age 50, and one with a typical 1979 haircut. police released the pictures to the public. >> we were hoping 100 would call in and say that looks like this person. the problem is we got 250 people call in and say it looks like 100 people. >> more needles. more haystacks. >> we went down a lot of rabbit holes. i tracked another 50 people. swabbed them. each time hoping we finally got our guy. >> with each test result, the hope was dashed. in 2018, they help solve the golden state killer case using a new technology called genetic genealogy. >> i get an email saying check out what we did. >> that offered a similar genealogy search using the dna from the crime scene. they would try to identify relatives of the killer by searching through genetic profiles on an online database. he gave them the green light. >> we said in the spring of 2018 and by the summer they sent a report and they said they had found a relative of our killer. >> a relative of the killer? >> they hypothesized she was a second cousin once removed from the killer. >> there's a headline. the person related to the killer was a woman in vancouver, washington. the trick was to build a family tree to see if police could link a family member to cedar rapids in 1979. he reached out to the woman and she agreed to answer his questions. >> we have to start building her family tree. >> they trace the family tree back to the earls. you're looking through historical records and census data. >> absolutely. tombstones. anything we could find. >> he created four branches going back to great-great- grandparents. the first branch led to someone living in ohio. he got a dna sample. >> we sent the dna sample back and they recalibrated and told us we can eliminate that branch of the family tree. >> don't waste your time. >> that person shares note dna with the killer. this one in nebraska and sent that in. same thing. get rid of that one. we don't need to worry about that branch of the family tree. >> on the next branch, he found a relative living in iowa. you have a live one here. >> we have a live one here. she's only 20 minutes away. >> she is not the killer. >> we always knew the killer was a man. we send her dna in. she shares enough dna with the killer to be a first cousin. >> it turns out she sure dna with first three cousins. three brothers. after four decades and so many disappointments, the list had narrowed to three. >> all three are still alive. still in iowa. >> what do you think? >> we are ecstatic. you can taste it at that point. we are ready to go. >> detectives are about to get up close and personal with the three brothers without them knowing it. coming up. >> he and his son leave and we grabbed the cup of the table and my partner was close enough grabs the straw and class and packages it up and we disappear. >> not a confession but not a denial. >> did you murder somebody? >> test the dna. and often out . but this is my story. ( ♪♪ ) and with once-daily trelegy, it can still be beautiful. because with 3 medicines in 1 inhaler, trelegy keeps my airways open for a full 24 hours and prevents future flare-ups. trelegy also improves lung function, so i can breathe more freely all day and night. 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. ♪ what a wonderful world ♪ [laughing] ask your doctor about once-daily trelegy for copd because breathing should be beautiful, all day and night. (luke) this will be a gold mine of local intel. (marci)cause breathing so, tell us about this corn festival. (stylist) oooh you got your corn pudding... (marci) so...is it safe around here? (stylist) sometimes. [luke gasping] (marci) no eyebrows? (luke) think of how light it'll feel in the summer. we gotta run. eleven thousand more neighborhoods to go! (vo) ding dong! homes-dot-com. 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>> no. >> they are leading respectable middle-class lives? the family name was burns and all were adults in 1979 but did not seem to have a connection to michelle martinko. the investigator and two colleagues decided to secretly collect dna from all three. this is when you become a double agent. its shifting gears. >> it is. >> they track the brothers starting with the middle brother. a married father of three, he sold farm equipment in manchester. about a 15 minute drive from cedar rapids. >> we collected his dna from is trying to goes to the state lab. they told us, he is not your suspect. the next brother was donald. >> oldest brother donald was a father of three and had five grandchildren. he lived in davenport, iowa, and the manager of a lumber yard before retiring. he went to the house and staked it out. >> the first item was out of a trash bag. we found a toothbrush and collected dna off of that. >> what did the left think? >> they said the same thing. he is not your guy. >> it came down to the youngest brother jerry burns who lived and worked in manchester. they did and tell on him. >> in 1979, hit two young kids. he sold farm implements and was in a bowling league. >> married with children. >> on an october morning in 2018, he and the team set out for manchester and three unmarked cars. >> it will come up on us. >> police followed him and finally at lunchtime, and the opportunity. burnson a son pulled into the pizza ranch restaurant. >> he parked there and was sitting at a booth by the window. >> they went in and sat in a booth. the next booth over? >> i am as close to him as we are right now. it's hard to enjoy your food when you're staring at the killer. >> burns was drinking a soda from a straw. the detective didn't take his eyes off of it. >> he and his son lee. we grab the cup and my partner puts gloves on and grabs the strong packages it up and we disappear. >> the sample was sent for testing. jerry was not only the last burns brother but the last possible suspect. he will never forget the moment he spoke to the contact at the crime lab. >> he said that is your guy. >> he is the killer. the lab reported the scientific probability was 100 billion to one which meant the dna belong to jerry burns and not anyone else on earth. finally, it was the culmination of a relentless decades long investigation. but he was not ready to make an arrest. there were too many questions that needed answers. >> it's time to talk to him. he is not going to be ready in that's up as time. >> 2018, he headed back to manchester. a pulled up to burns place of business a little before noon. the door was open. he walked in. a hidden camera recorded everything. did you have backup? >> we had a lot of backup. we had no expectations of what to expect from him or his behavior. >> what is in his desk drawer? he introduced himself and said the mug down on his desk. >> he sits there and he's patting his shop cat that's climbing all over the desk during the interview. >> you have a cat here. >> he handed burns a business card and got down to business. >> we are following on an old case. >> he described the computer sketch that was developed from dna found at the crime scene. he said someone called in with a tip and that's how burns name came up. that was not true but he wanted to see how he would react. >> that is the picture we created. >> it looks different. do i look like that? >> i think you do a little. enough that we bothered to come up here and talk. >> burns remained calm and denied knowing michelle but didn't say much more. you're holding the card here. here is what science says. do you confront him? >> we directly confronted him. >> we have your dna at the crime scene. we know you were there the night a happen. how would we get your dna there? >> i don't know. test it and see if it is. >> we did. how would it be there? what happened that night? did you murder someone that night? >> test the dna. test the dna. >> it was not the confession they were hoping for but he didn't think it was a denial either. 39 years to the day after michelle martinko's murder, he was cuffed and placed under arrest. >> you have the right to remain silent. anything you say can be used against you. >> the charge was first-degree murder. for jerry burns daughter, the news was a gut punch. impossible to comprehend. >> it almost seemed like a dream that it was not really happening. >> could you believe it? >> no. my brother said dad has been arrested for murder. i was like, who? i was in disbelief. >> the arrest did not square with the image of the devoted father, the good kid brother they had always known. they felt certain there was something wrong with the dna evidence. >> there's lots of other stories where there is a mistake dna found at crime scenes. there is an explanation for why it is there. doesn't mean who's ever dna it was is the person that committed the crime. >> there is nothing to substantiate when it came there. how it got there. >> you say this cannot be right. >> no it cannot be right. >> the family was convinced he was innocent. could prosecutors convict a jury he was guilty? 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>> it was described as violent pornography. >> featuring young blonde women? >> blonde women was a search term used. >> the defense attorney filed a motion to bar the computer evidence from the trial. >> it was not germane to the case. it was found in mr. burns computer 39 years after the crime. >> and a pretrial hearing, the judge agreed dealing a blow to the case which boil down to a single piece of evidence against jerry burns. the dna match. >> good morning ladies and gentlemen. >> the trial began on february 2020, michelle martinko's sister and husband traveled to attend, determined to see it through to the end. >> every day. if the jury has to be there, we will be there. >> the prosecution with the detective on the stand to tell jurors the police followed sound practices when they handled the clothing. >> we wore rubber gloves for one thing. we tried not to disturb the clothing items. just a quick look and then reinsert them back in the original packaging. >> a dna analysts testified the dna collected from that evidence could only belong to one person. >> the probability of finding two unrelated individuals is so small that it can be discounted. >> the defense attorney was not rolling over for the dna case. >> jerry 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. he argued key items like michelle's dress word jumbled with or other clothing, tainting them forever. >> when you opened the original packaging of the dress, panties, and pantyhose, with a items bundle together? >> as far as i recollect they were. >> there was another reason to question the defense attorney said. something called dna transfer. he quizzed his own expert witness. >> is it a plausible explanation the dna of jerry burns found on the dress or the gearshift could have come about by a transfer? >> yes. that is a distinct possibility. >> the dna expert told the court that burns might've left his dna on a door or a bench. after all, he told investigators he had visited the mall. >> the defense argued he was a victim of coincidence and sloppy police work. >> ladies and john wick, the evidence has been submitted to you. >> after eight days, the jury got the case. when it goes to the jury, what are you thinking? >> we are hoping for the best. if he was not guilty, we have my dad home. if guilty, it meant more work. more fighting for him. >> janelle was worried for another reason. sheen of the prosecution's case , dna testing and it was complicated. >> i taught fifth grade. i know how hard it is to teach somebody something. you have to repeat it over and over again. i am concerned about that. >> as it turned out, the jury reached a quick verdict. the judge read the decision allowed. >> we the jury find the defendant jerry lynn burns guilty of the charge of murder in the 1st degree. >> how did he take it? >> i think he was shocked. he was expecting to come home. >> i was surprised at the verdict. i had a hard time believing the jury sat down and yvonne reviewed the case. >> three hours. >> not even three. >> i couldn't believe they came back with the verdict they did. >> outside the courthouse, john and janelle . >> 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 worked on the case. i felt like we as a team had finally done justice for the martinko family. >> jerry burns was sentenced to life without parole. >> as we were looking through pictures, we realized that she was not part of the christmas. she was not part of that birth. she was not 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 it. >> she is not in it. >> she's only in the old photos. a girl smiling out into a world of possibilities, stolen on a cold december night. >> that is all for this edition of dateline. i am craig melvin. thank you for watching. watchin i'm craig melvin and this is dateline. >> i got a call saying that the house was on fire. the first thing they asked me was, who would want to kill you, who would want to murder you, and i just kind of looked at them like what?