Last month have a duty to denounce trump more so than ever, or whether you just be funny. At least we found somebody who is enjoying this campaign. It is hard. They are not journalists, they are entertainers, and their job is to entertain. Its not to, you know, put in the minds of the public, you know, thingd d about candidates which they are not qualified to be putting forward. But they do essential truth about these candidates. So from a political adviser perspective, we try to mitigate their weaknesses. They reveal who they are. Thats part of this process. Its a full reveal. They are the mri technicians of american politics. Programming note, msnbc will have live coverage of a town hallstyle faceoff between donald trump and hillary clinton, the most surreal debate in amerqun history, i can promise you that. S 9 . lc thats all we have today. Be back next week. Because if its sunday, its id lay in bed with my imagination and i would play out possibilities of what happened that night. I thought about how scared she must have been. It was hard to go to sleep some nights. A young womaniving on her own, murdered in the middle of the night. She was vulnerable, alone and in bed. A crime that jolted a sleepy seaside community, a killer walking among them. I dont think it really sets in that were all a little more young, fun and pretty. Corey had plenty of admirers and one of them liked her too much. A strange coworker. I want to know who this is. That is scary stuff right there. Exactly. And an adoring friend. Her statements about how much she loved corey piqued her interest. And a young man who made some people uncomfortable. She called him a creeper. A gallery of suspects, piles of evidence, but the truth would only be revealed by a tiny, telltale clue. Did everyones eyes drop . My eyes filled up with tears. I couldnt believe it. Im lester holt and this is dateline. Heres Andrea Canning with rear window. Reporter maybe it was the then again, maybe it was just the booze or the talk of some easy money. Were all just sitting there having a couple beers fishing, relaxing and enjoying. Reporter somehow, Three Friends kicking back on a lakeside dock found their evening sliding into the past, a brutal unsolved murder, an investigation stalled, an old name resurrected. As they grew wide. What is your gut telling you as youre sitting on that dock . Were probably on to something. Reporter and someone whod prefer to stay hidden. Strange how the night can shine a light into the darkest places. Like so many others, corey parker came to florida for the waves and weather, but she stayed for the people, like amy laden. I do. Reporter corey a young 20something when she and amy became fast friends. We were at petes bar on the beach, and we were actually in the bathroom waiting in line. Reporter and what did you say to her . I think she started the conversation and just said, hey, i see you around all the time, you know, we should hang out. I said all right. Reporter did you two get into a lot of trouble . Um, we didnt get caught doing things, or we probably would have. Reporter corey was a transplant from york, cowering and sweet like a sugar maple. Corey was 511, and she would wear heels, so she was so tall, and im very short. So, i think every time she walked into a room, people looked at her, and she was so beautiful. Reporter did she kind of look like a model, being 511 . Yeah, she could model. She could definitely model. Reporter instead, she chose a humbler route, taking classes at the local college and waiting Jacksonville Beach. Amy says that was pure corey. Did she like being a waitress . She loved it, because she could talk to people, and she was super friendly. Reporter she was a people person. Yes. Reporter another reason she loved corey, both were fiercely independent. Corey in particular had just moved into her own apartment. This is absolutely an exciting moment for her moving into this place because she was finally being able to do it on her own. Reporter this was a big kind of Independence Day for her, then, moving into this apartment . It was a yeah. I was excited that somebody else was going to be moving in that i might be able to talk with. Reporter ashley berg remembers coreys movein day that september of 1998. Ashley, then 18, lived next door with her mom and older brother, joe. Corey at 25 seemed like a big sister. We would sit outside. She would do her laundry. Wed have a little glass of wine and just talk. Reporter about work, school, and coreys new boyfriend, a favorite latenight hubs, the ritz. Ashley sensed her neighbor was falling in love. It started getting pretty close for them. I really feel like that. Reporter but there was something troubling, too. Corey was feeling uneasy about her groundfloor apartment. Her bedroom and front door were across from another building. It was someone else in our building that saw a peeping tom and saw that someo into her window. Reporter ashley says for that reason, corey preferred hanging out in the back of the apartment in the kitchen. Thats where they were the day before thanksgiving. Corey was making dessert to bring to a friends house for the next days feast. So, we drank a beer, started making some pies, and she was telling me about thanksgiving. She was telling me where she was going. And i didnt even know she could bake. Amy, who had left town for thanksgiving, remembers being tempted to stick around Jacksonville Beach so she could party with her best friend. Looking back, i wish i had, but i opted to go down to my moms the night before and spend the night. Reporter photos from that night show corey inside her hangout, the ritz. Shes seen looking back at the camera. One of the women there was a new friend. Her name was tiffany zienta. We were young and all in college and felt wed just all go hang out. Reporter you and corey went out a lot. We did. Reporter your relationship kept getting closer and closer . Yes. Well, on my part. I cant answer for corey, but yes, from my vantage point. Reporter that night, tiffany says, corey, usually the bubbliest in the room had fizzled out early, around 1 30 a. M. We left at the same time. Reporter how do you part ways . Reporter she says corey promised to stop by her place the next day, but thanksgiving came and corey was a noshow. I didnt think much about it. But i did tell my mom that i was a little bummed out that she didnt call and didnt come by. Reporter was that like corey to not call and say no, not at all. Reporter is she the type that would say, hey, im going to bow out for tonight . Correct. Reporter it wasnt until the day after thanksgiving, black friday, that someone finally noticed corey missing. She t morning shift at the restaurant. No one had heard from her in more than a day. So one of the cooks, who was a friend of ours, said ill go check on her, because she didnt live far from where she worked. Reporter the man returned to the restaurant to report that corey hadnt answered her door. Alarmed, the manager sent him back. He walked around the back of her apartment, and her blinds were closed in the back, her bedroom, but there was a little there was blood on her foot. Reporter the coworker immediately raced back to work in a panic. Police were called. Corey parker had just been found. What had happened to corey . Inside her apartment, the first chilling clues. You could tell that she had fought for her life. And why detectives are sure her attacker was no stranger. That speaks to some sort of a relationship. . . . . . . . . . . Geico motorcycle, when you ache and havent slept. Youre not you. Tylenol . Pm relieves pain and helps you fall fast asleep and stay asleep. We give you a better night. 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Wow, that sort of blindsided me. And it clears my terrible cold symptoms. Ahh this is awkward. New Mucinex Fastmax clear cool. Feel the menthol burst. And clear your worst cold symptoms. Start the relief. It was just before noon on black friday. Ashley burg woke up to banging at her front door. It was the police. Theyre like, are you corey parker . And i said, no, im not. I said, i point at kind of like the window next to me, which was her house, and i said, she lives right there. Reporter moments later, officers were in coreys apartment. They had said there she is. And i just fell to my knees. Reporter 25yearold corey parker was dead. It was clear shed been murdered. Investigators called state attorney angela corey, then an assistant prosecutor. The police were all there when i arrived, and so they walked me through the scene. Reporter how hard was it seeing corey parker in that way . It was brutal because you could tell that she had fought for her life. Her most vulnerable alone and in bed and that she had been, you know, brutally and viciously stabbed in the middle of the night. Reporter stabbed more than 100 times. This was a sick individual who did this. Very, very. Reporter it didnt take long for word of coreys death to spread from the tiny apartment. Amy lavin, still visiting her mother out of town, got a call from coreys boyfriend. And he said, did you hear whats going on . Im so confused. I said no. Whats wrong . Everythings fine. And he said, corey, theres something wrong with corey. Somebody found her in blood. And i said, no no, shes fine. I talked to her yesterday. Everythings fine. Reporter still, she drove back to Jacksonville Beach, straight to the Police Station, just to make sure. Did it finally register at the Police Station eventually . I went into a room with a detective. Found in her home dead. I kept thinking, something happened to her heart. I dont know why i kept going back to that in my mind. I dont know why. Reporter tiffany zienta, who had been out with corey two nights earlier, was finishing her bartender shift when a customer broke the news to her. I had this feeling kind of wash over me and called amy and asked her if it was true, and she saidwa reporter detectives on the scene, meanwhile, were busy talking to coreys neighbors and sizing up the layout and location of her apartment. That in itself was a red flag. My first time here at first glance doesnt necessarily feel like the safest situation for a young woman living in this groundfloor apartment. Right. Theres a lot of transient traffic that comes through here. The beach is three blocks from here. Reporter detectives billy she was a beautiful woman. And whenever she would walk to and from her apartment, im sure there were a lot of guys that were looking at her. Reporter theres a lot of apartments around here. You must have had to do a lot of canvassing. We did. Yes. A lot of individual canvases. We had to talk to every one of those people, document it all. And theres a lot of partying that goes on at the beach, so you have people wandering up and down the streets here at 2 00, 3 00 in the morning sometimes. So yeah, thats a concern. Reporter neighbors told police there had lately been a peeping tom creeping around the area. So it was possible she was killed by a complete stranger who had broken into her apartment. It looked like that the suspect had put his hand on the kitchen counter, right there at the lip of the sink, in order to lift himself up on the cabinet to be able to extricate himself from the window. You could see what almost like they lowered themself out the window. And those were in blood. Reporter it was coreys blood, traces of her murder left by the killer. But the idea that this was a random killing didnt sit well with detectives. Was your gut telling you that this was someone she knew . Yes. Yes. Reporter what was it . Why were you thinking that . Well, because of the extensive stab wounds. She was stabbed 101 times. And that speaks to some sort of a relationship. Reporter they hoped to find traces of her killer in the mess left behind. There was plenty of evidence to test fingerprints on wine glasses and cigarette lighters, hair and blood everywhere. You just never know whats valuable. So you try and photograph everything, then you try and examine everything that you can, that you think is potentially involved in it. Reporter and everyone. The first person they needed to talk to was the new man in coreys life. You all wanted to talk to the boyfriend, a logical place to start. Any red flags there with him . We determined through plane flight tickets that he was out of town at the time. He wasnt even here in Jacksonville Beach. Reporter was it a solid alibi . Yes, solid confirmation. Reporter but these were early days in the investigation, and there were many people in coreys world for police to rule in or out, including a man who lived right next door, ashley burgs brother. Police had a reason t him. Coming up reporter did he have a solid alibi . No. Questions about a neighbors whereabouts, and then suspicions about a coworkers feelings for corey. Do you think you were obsessed with her . . . This was lowkey Jacksonville Beach, florida, where the main concern of the day was how high the waves were riding. A young, single woman attacked didnt happen here. I think this case goes straight to every womans nightmare, that as hard as corey parker tried to be safe, and she had all of her doors locked, she still was the most vulnerable in the sanctity of her own home. Women who lived alone were scared. Reporter melissa nelson, then an assistant prosecutor who joined the case, recalls the fear. Neighbors were scared, people she worked with were alarmed. So, it was a very scary time for reporter tiffany zienta, raised in jacksonville, beach, couldnt believe this had happened to someone she knew. I mean, they kept calling it the bloodiest crime scene in Jacksonville Beach in 25 years. Thats not really comforting to feel or to hear. Reporter ashley burg was also frightened, for another reason. Detectives thought her brother joe had been too vague about where hed been in the hours surrounding coreys death. Did he have a solid alibi . Not really, no. Reporter what was he doing . Apartment just hanging around. And he comes and goes. So we couldnt really establish a solid alibi at the time of the crime. Reporter their interest grew when they found a hair on a sock in coreys bedroom. The hair looked like it could have come from joe. I know we did a microscopic comparison. And that the microscopic comparison developed that likeness. Reporter the test they used back then wasnt definitive, but it was enough to make Police Suspicious and for joe to worry. Th is your hair on her sock . He couldnt answer that. He was petrified. Petrified. He didnt know, you know, what they were going to do next. Reporter what police did was take a sample of joes dna for testing and press on. Meanwhile, there was another young man they were interested in, a dishwasher named eric ealy. Eric was a coworker that worked with corey at ragtime he really liked corey. Had come on to her on multiple occasions and had also done that to several of the other waitresses up there. They just thought he was a creepy guy. Reporter who had grown stranger by the day. Police found out hed been pestering corey to have thanksgiving dinner with him alone. Each time she turned him down. Detectives brought the young man in for questioning. Did you ask corey out for thanksgiving dinner prior to calling on i know i didnt ask her a direct question. Reporter but to the detectives, what the dishwasher did next was a move straight out of a norman bates playbook. He made this really nice thanksgiving dinner in hopes that he could call her and say, ive made thanksgiving dinner. Id like for you to come over and enjoy thanksgiving dinner with me. Reporter so he made the dinner first . Yes. Reporter and then called . Right. Reporter thats a tiny bit on the creepy side. Reporter it was clear he was infatuated. Do you think that you were obsessed with her . Yeah, i was slightly obsessed, but i wouldnt do anything you were greatly obsessed, eric. Jesus admit it. My god. I was. I was obsessed. Reporter from there, the interview took an even darker turn. The young man admitted to violent fantasies. Tell me the things that you think about doing with women that you wouldnt do because you know its not the right thing to do. You mean like taking them into a bedroom and raping them . Yeah. Reporter hes talking about rape. Thats scary stuff right there. Exactly. Reporter that paled in comparison to what he said next. He described how he thought corey had been killed. How would you contain her . Taking her down until she was tired. And just poked her, you know, whatever, stabbed her. Slit her throat. Reporter in fact, thats how corey was killed. Did you think about the scenario rejected by corey and he snapped . Anything is possible, yes. I mean, that comes into your mind, you know. He asked her multiple times to go out with him. And although she was cordial to him, she just never went there. You sound like you know a little bit more of what happened to corey. How would you how would i know . Because maybe maybe i would share the same thoughts as this person that did it. Reporter he sounded like an obvious suspect. I would like to have fantasized myself doing it but i didnt do it. Reporter despite all his incriminating descriptions, the dishwasher was adamant he hadnt killed corey. And police didnt have any hard evidence that put him inside her bedroom. Hes got a denial. And you got nothing to put him there. Reporter for the time being, police had to let the man go. And just when it seemed their case couldnt get more complicated, it did. Coreys friend had been talking things that catch a detectives attention. Coming up are you ready for another potential suspect . This close girlfriend of coreys. Was she a little too close . Tiffany was infatuated with corey . Yes. Her statements about how much she loved corey piqued our interest. What are you doing right now . Making a cake uh oh. I dont see cake, i just see mess. Its like awful. It feels like am not actually cleaning it up. doorbell whats that . Swiffer wetjet. This is amazing. Woah wow. Now i feel more like making a mess is part of growing up. Only new wetjet pads have absorb and lock to soak up tough messes and lock them away when its time to potty train. Its time for training underwear new pampers easy ups. 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Tv character taking selfies in the kitchen in the months after corey parkers murder, police had several potential suspects, including a nextdoor neighbor with a vague alibi and an obsessed dishwasher, but they didnt have enough to make an arrest. Coreys family even offered a reward for information. Former prosecutor melissa nelson. To that end, everybody who presented as a potential suspect, they were running that to ground. Reporter amy lavin found herself looking around at coreys other friends and wondering, could it be one of them . Everybody was an actual suspect. So that became a little bit scary to me. Reporter her killer could have been right under your nose. Yeah. Reporter tiffany zienta remembers just wanting to be helpful. Like most of coreys friends, she met with the detectives. They want to talk to you, detectives . We all made a statement. Reporter well, they wanted to talk to. Absolutely. Reporter tiffany told the detectives shed been with corey at the ritz bar wednesday night into the earlymorning hours of thanksgiving. She said they left the bar at the same time, around 1 30 a. M. Tiffany hitched a ride with another friend to go bar hopping. Corey, she noted, got into her own car and headed home. Later, tiffany said, she called coreys home phone. It was like 2 15. It was right after we left the original bar. Reporter detectives followed up on what tiffany had told them. Noticed a wrinkle in her story. Her phone call was not on the phone records of corey parkers home residence phone. Reporter so shes starting to make some inconsistent statements. Exactly. Inconsistent statements. Reporter more troubling to police was what they were hearing from coreys friends. They were saying tiffany had been describing the murder, the stab wounds to the body, details that hadnt been made public. They also believed she harbored deep feelings for corey that werent mutual. Corey . Yes. Reporter what were you told . We were basically told that it was bordering on a little strange, you know, with what we heard about her statements about how much she cared about corey and how much she loved corey, it piqued our curiosity and interest. Reporter now detectives wanted to sit down again with tiffany, but by then more than five months had passed since coreys murder, and tiffany had the move only made her look worse to police. So, they tracked her down, hoping to confront her, but tiffany wasnt having it. She at some point decided she wasnt going to cooperate further and referred us to her lawyer. Reporter so detectives decided to get a warrant for tiffanys dna. We had to get a court order to get her standards, her hair, and her blood. Reporter are you starting to think she could be coreys killer . Well, you just have to follow that lead. We felt like, based on what we knew to that point, that she was a person of interest definitely. Maybe a viable suspect. Im not the person thats going to kill somebody. Reporter looking back, tiffany is convinced detectives set their sights on her from the moment she first talked to them. The fact that she was the last friend to see corey alive, she says, shaped everything that followed. Going to come back to haunt me. You know . Police were like, well, the killer was the last one. Well, until you think about it that way, you dont think about it that way. Reporter first of all, she says, she never lied about that call to corey, no matter what the phone records said. How do you explain that . According to my attorney, he had had other clients that had called people that didnt show up on phone records either. I dont know. I dont know why it didnt show up. Reporter as for being in love with corey, is there any truth to that . No. Because im not gay. I thought she was beautiful. I thought she was a great person. Have i been infatuated with corey . No. Reporter Everything Else she did in this case, she says, was out of innocence or panic. She learned about the bloody crime scene from a friend, a paramedic who had been there. She went to new orleans to rest, not guilt. How are you feeling as this is getting more intense . I mean, this is a murder investigation. Helpless. Bullied. Helpless. Like there were going to be no answers. And this was going to be hanging over me for the rest of my life. Reporter but before they could make an arrest, detect crime scene. Thats when things got really interesting. Coming up yet another person of interest, this one lurking in the shadows. It wouldnt take much if she had her lights on for him to sit up there in the dark and be able to watch her. And then detectives get their hands on the one thing that might solve this case. We were jumping for joy. When dateline continues. Hor cafe au lait . Oh, its actually. Sfx short balloon squeal im being so serious right now. 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Reporter but she wasnt arrested, and neither was anyone else in the months following state attorney angela corey. So this wasnt solved after the commercial break . Oh, no. No, no. We went into this knowing we were in for the long haul. As they, whats that phrase, we knew it was going to be a marathon, not a sprint. Reporter they had their list of possible suspects, but they didnt have the evidence or the science yet to definitively link anyone to the crime. Dna testing was actually in the middle of evolving at that time. Reporter eventually, the science and the evidence came together. Inig of foreign hair from coreys underwear. They believed that single strand was rich in dna. It had been clearly ripped out of a head. Reporter likely, they believed, the killers head. Now they had to test it against their possible suspects. You essentially had your killer in your test. You just didnt locked in a tube. Reporter didnt know his name . Hairs on slides, thats yet, thanks to this man. Would you call yourself a Bounty Hunter . Ive been called Bounty Hunter before, but id prefer fugitive specialist. Reporter fugitive specialist. Okay. William rensler knew about coreys murder, and he knew there had been a reward posted for information leading to her killer. So it was kind of like, hey, why not take a look . Yeah. Reporter so on his own he started talking to coreys old neighbors to see if officers had missed anything. When i came across the one individual, some things struck me as odd. Reporter the individual was a young man named Robert Denney. He was 17 years old, living in a nearby building when corey was killed. Hed been questioned and dismissed by detectives early on in part because he was so young. What seemed odd to william was that the teen disappeared not long after the murder. As memorial day weekend rolled around, william found himself on we were fishing and having a couple of beers, and i was going over my notes. Reporter suddenly, he remembered that Robert Denney had worked at the same restaurant as his friends. They recognized the name instantly. They felt that he was an offbeat individual. Reporter about two months after the murder, they said denney seemed distraught, saying that he had to go home to texas, saying that his child had just been killed. They quickly found out that hed made it all up. So hes a liar . Correct. Victim. Correct. Reporter he moved out of town shortly after the murder. Correct. Reporter what does your gut telling you as youre sitting on that dock . Its highly unusual, and were probably on to something. Reporter william shared his suspicions with detective katie kingston. She then went over to check out denneys old apartment for herself. You can see how close it is. Reporter it was apartment number 4, and its back balcony was less than three feet from coreys old kitchen. When police met with denneys woman from his balcony. Do you think hed been watching her for a while . Absolutely. Yeah. No question about it. Yeah. Reporter it was something straight out of hitchcock, a rear window, a vulnerable young woman, a man watching, seeing but unseen. Denney didnt match the description theyd gotten earlier in the case of the peeping tom, but that didnt mean he hadnt been spying on corey, said detectives. It wouldnt take much if she had her lights on f up there in the dark and be able to watch her as much as he wanted to. Reporter kingston didnt know where the man lived now, but she found out he had a sister in the area. What the woman told the detective about her brother was unsettling, to say the least. She called him the night creeper. She said that he would creep around the house at night. She had woken up before and he was staring at her. Reporter the sister said kingston could find her brother in easton, maryland. Kingston and carlyle immediately headed north. They needed to compare their suspect to that hair sample from the crime scene. You need his dna . Absolutely. Reporter with the help of easton police, they called up their suspect and flat out lied. They made up a story about a recent assault. Could he come in for questioning. So he agreed to come in and he sat down with us. Reporter what followed was vintage cat and mouse. Police tried to get denneys dna off a cigarette. Denney went for the smoke, but when he was finished he took the cigarette butt and put it behind his ear. Wouldnt put it in the cigarette ashtray. Reporter so they moved on to plan b they offered him a bottle of water. He takes the water, but he doesnt take the top off of it. He sat there the whole time never drank from the water bottle. So now youre on to plan c. Reporter which was this. They asked denney to fill out some forms, Police Procedural stuff, they said. And what we were going to do then put them in an envelope and then seal the envelope. There was three different envelopes. Reporter denney filled out the forms but didnt lick the envelopes. And he looks at us and says, you guys have tried three separate times to get my dna sample. He says, you can seal them yourself. Is there anything else . Reporter the best laid plans. The best laid plans of mice and men. He didnt fall for it. Reporter denney was done, but carlyle wasnt. I wasnt going anywhere without a dna sample. Rep out at the Computer Store where he worked. And snapped these photos as their prey came outside for his cigarette breaks. Once again, their mouse was a step ahead. He was smoking a cigarette and when he was finished with it, he would take it and put it behind his ear. Reporter do you think he knew that maybe you were watching him . Im sure. Reporter but on the second day, denney did something he had he starts spitting on the ground out of the clear blue. Reporter spit has dna in it. And we were like we were jumping for joy at that point. Reporter so youve never been so happy in your life to see someone never so happy to see that. Reporter spit. When denney left, carlyle raced over, collected the sample and drove straight to the fbis dna lab. All there was left to do now was wait just a little bit longer. Coming up no matter how the tests come back, detectives will have to explain a lot of other evidence at the scene. Theres unidentified fingerprints and theres unidentified hairs in the victims hands. Had someone else been at coreys . And then, we sit down with Robert Denney. Reporter did you murder corey parker . The reason denney says police it had been a year and a half since corey parkers murder when police discovered or rediscovered Robert Denney, her old neighbor. We were full bore on Robert Denney at that point. Reporter heres why. Denney lived right behind the victim, he disappeared soon after her murder, and detectives learned this denney had an older ot youre starting to think this might run in the family . You cant help but think that. Reporter denneys brother had been convicted years earlier in texas. And his crime was eerily similar to this case. The interesting thing about the brother was that, in his case in el paso, he stabbed that woman 96 times. And were dealing with a homicide where our victims been stabbed 101 times. So the similarity was just too much to overlook. Reporter the detectives had outdo his sibling. One thing detectives were sure of, he had become fixated on her. A coworker recalled being in Robert Denneys apartment. Robert pointed down to coreys window and said, i watch that girl down there. Reporter they were convinced denney was her killer, but they needed proof. So they waited for tests to compare denneys saliva sample to that strand of hair found at the scene. And wouldnt you know, denneys not just to that hair but also to a tiny speck of blood recovered near her kitchen sink. All the other possible suspects, the nextdoor neighbor, the dishwasher, and tiffany, were cleared in the case. We were jumping up and the down. We wanted to go get him then. Reporter and prosecutor angela corey said no. He can come up with a story to explain that dna away. Oh, i carried her groceries in to explain it away. Reporter the prosecutor wanted him on the record denying hed ever set foot in the victims apartment. Then theyd hit him with the dna proof, trapping him. So they sent katie kingston back to maryland to Robert Denneys house. Well, i was going to play like i didnt know anything. Reporter you were acting. Just acting kind of dumb. Reporter she told denney they had found the man who parker. The detective was just here to tie up loose ends. He seemed willing to help. What he didnt know, the detective was wearing a wire. Do you know corey parker or ever talk to her . No. No . Uhuh. Okay. No. Reporter then the detective asked the crucial question. Had he ever been in coreys apartment . So yall didnt go back and forth to each others apartments . I knew the guy next to that. No. All that stuff. Okay. Reporter that was all the detective needed. The cat, it seemed, had finally gotten its mouse. When we heard the recording, i had the arrest warrant ready to go, and i finished plugging in what they told me over the phone, and we were ecstatic. We knew we had him. Reporter corey parker had been dead almost two years to the day when police slipped the handcuffs on Robert Denney. At the Police Station right after his arrest, he protested you cant have any evidence. Its impossible. Because i didnt do it. I cant admit something i didnt do. Reporter and when carlyle mentioned denneys brother, he again told the detective he had it all wrong. Thats my brother. I understand that. Thats my brother. I understand that. Thats not me. Reporter detectives werent buying his tears. They were convinced they had enough evidence to put Robert Denney away for life. Years to bring him to trial. It was, after all, a complicated investigation. Denneys dna was found at the crime scene, but there was also evidence they couldnt link to him. We had alternative suspects. We had a lot to explain in the form of the science. Reporter the defense seized the opportunity, noting there were any number of people who might have killed corey. Theres still unidentified pieces of evidence at this crime scene. Reporter Robert Denneys attorney, rick sitka. Theres unidentified semen stains, theres unidentified fingerprints, and there is unidentified hairs in the victims hands. So, its a question of who done it. Reporter not a case of denney did it, he said. To underscore that, denney even took the stand to show jurors he was just a boy next door, not a monster at the door. Only it didnt work. After a threeweek trial, the render a verdict, guilty of firstdegree murder. Denney was sentenced to life in prison, which is where we met for this interview. Did you murder corey parker . No, i did not. Reporter he believes the sins of his brother made police quick to zero in on him. There has been a connection made as far as the theories of the police, the prosecutors that this was some twisted brotherly bond or rivalry. None at all. Simply because my brother is convicted of murder does not make me a murderer. Reporter he says the way police later got his dna shows they were determined to link him to coreys murder. When i first heard that my spit was what they collected to match to any dna at the crime scene, it was just unreal. Im thinking to myself, how could this be . Reporter hes also convinced that the labs, including the one dna against the evidence from the crime scene. Theres definitely evidence that suggests they may have mixed up samples. Reporter i think the hardest part to wrap your head around is that there could be contamination on both the blood and the hair. Right. I can understand why you would feel that way, and maybe that goes to explaining what the police might have done with the evidence. We dont know. If i knew, i wouldnt be here. Reporter it just seems a little farfetched that th police would randomly pluck you out of obscurity years later and decide to frame you. I understand. And ive thought about this for years, and it happened. Police do frame people. We see it all the time now in america. Reporter the police have framed you and two separate crime labs have contaminated the evidence . Yes. Reporter you can see how that i can see how that is very farfetched, yes. I can understand that. Reporter the detective in this case says he is 1,000 certain he has the right person. Hes wrong. He does not have the right person. Reporter so who did it then . If i knew, i wouldnt be here now. I wish i knew. Reporter yet, the people who arrested and prosecuted denney insist two independent labs did follow protocol, linking his dna to evidence from the crime scene. Still, denney is hoping a recent postconviction motion, arguing in part that the dna testing was flawed, will result in a new trial. His family and supporters are even blogging about his case. That infuriates coreys friends. I hope he rots in hell. I hate Robert Denney. Reporter as for tiffany zienta, she says it took a long time to get over what he and the police did to her. How did you deal with it . Drink. Tried to lose who i was. Tried to change who i was. Didnt like myself very much. Its taken me a while to get back to who i need to be. Reporter amy lavin has also struggled with the past. I go to that day. Why didnt i invite her to thanksgiving with me . Maybe she would have gone. So, even to this day, you know, theres a lot of guilt with that. Reporter but theres also gratitude to investigators who never ga strangers on a dock playing armchair detective, and most of all, to a best friend. I definitely feel blessed to have known her for the amount of time i did. I cant imagine what she would have accomplished by now. Reporter whatever it was, amy feels certain it would have been like the woman herself, as vibrant as a northern sky, as unforgettable as a southern thats all for now. Im lester holt. Thanks for joining us. Announcer the following paid presentation for the power Pressure Cooker xl is brought to you by fusion life brands. Introducing the power Pressure Cooker xl, the revolutionary kitchen miracle with Onetouch Technology that infuses flavor into your food while cooking up to 70 faster. The power Pressure Cooker xl is sweeping the nation with over 1 million sold. And has been featured in bon app . Tit and cooking light magazines. 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