they did a great job, and it all came together. >> i've never had a case where the small things mattered so much, where something as small as a needle mark or the amount of dna left on a needle cap played such a pivotal role in the resolution of a case. >> her body was positioned in a way that was very sexually suggestive. >> it's hard to imagine anybody is capable of something like this. >> until one man's words reveal a twisted motive and a killer with a bizarre past. jacksonville, florida, with its warm, sandy beaches and

subtropical climate was the perfect place for 25-year-old corey parker to attend college. she liked it a lot better than the cold winters of her hometown of rochester, new york. corey was beautiful, she was very tall. she had a presence about her. some of our best times with her was a girl's night in. you know, rent movies and hang out at the house. >> corey worked her way through college as a waitress, during the thanksgiving holiday of her junior year, she didn't show up for work, so her fellow employees were concerned. >> they thought immediately that something was wrong. so the manager directed one of the cooks to go by her apartment to check on her. >> her apartment door was locked, but her co-worker looked inside and saw her body on the bed covered in blood. >> this crime scene was one of the worst that this county has ever seen in terms of its just

gruesomeness. there was blood all her bedroom, all over her body, almost as if it had painted on her. >> the scene appeared to be staged. >> corey's body was positioned in a way that was very sexually suggestive. she was nude, her legs were spread apart. there's every indication that there was a sexual motive to this crime. >> interestingly, the autopsy found no evidence of sexual assault. >> corey parker was stabbed 101 tiles. 1 is 101 stab wounds i believe 54 of them was postmortem. >> overkill does indicate a relation shi between victim and perpetrator. >> police learned that corey spent the night at a local bar with friends. witnesses say she left around

1:00 a.m. the clothes corey wore at the bar were folded neatly at the bottom of her bed. >> we also know that she prepared herself for bed so we know that she wasn't attacked until after she was in bed. either he was waiting in her bedroom closet or he let himself into the apartment. >> investigators found a gold-plated zippo lighter in corey's bedroom, although corey smoked, none of her friends recognized it. investigators dusted the lighter for fingerprints but none were found. >> it became apparent to us that there was no way that that was corey parker's lighter. >> inside the kitchen of corey's apartment police found a blood stain on the kitchen counter next to the sink. and on the window sill, above the sink, both inside and outside.

this led police to believe the killer entered and exited the apartment through the kitchen window. >> the reason we believe the killer didn't go out the door was because of the light that was outside. the kitchen window offered the suspect a way to get in and out of the apartment without being illuminated. >> corey's phone records indicate that a former co-worker 27 years ago eric jones had been calling her repeatedly before her death. >> he had been asking corey out for some time. she'd been telling him no. >> employees at the restaurant tolds that you he had an infatuation or was continuously talking to her when she came to work and was trying to ask her out. >> jones had no criminal record but acted bizarrely when

interviewed by police. >> not only did he have a history of mental illness by his own admission, but he told police officers that he had fantasies about raping and killing women which clearly jumped out at women. >> he described sexual fantasies he had about corey, some were fairly violent. >> he even told investigators how he would have murdered corey had he been given the chance. >> he described how he would slit her throat early in the murders so she couldn't scream for help. and that description was similar enough to how she was really killed that it again raised police suspicion. anything we purchase for the paper cottage goes on our ink card. so you can manage your business expenses and access them online instantly with the game changing app from ink. we didn't get into business to spend time managing receipts, that's why we have ink. we like being in business because we like being creative, we like interacting with people.

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corey had been stabbed over 100 times. there were numerous defensive moves on her hands and arms proving there had been an intense struggle. >> my theory is that corey parker fought for her life in order to prevent a sexual

assault. >> investigators found several foreign hairs in corey's hands. one had an intact root. >> the fact that the hair had root material on it and was not from her would allow you to at least presume that hair had to be attained forcibly. >> dna testing revealed the blood in the kitchen came from the same person as the hair in corey's hand. surprisingly, this dna did not match the prime suspect eric jones, corey's co-worker, despite his bizarre behavior. the dna from corey's apartment did not match any of the dna profiles in either the state or national criminal bases. in the search for corey's killer, investigators discovered that she had just started dating someone new. his name was david wilt. but it didn't take long for

investigators to eliminate him as a suspect. >> he was out of state at his parent's house for thanksgiving. so he had a very solid alibi. investigators interviewed everyone corey spoke with at the ritz bar on the night of her murder. most of the people corey saw that night left the bar before she did. but one friend, tiffany smith, stayed with corey until 1:00 in the morning. tiffany told police they both left the bar at the same time in their own cars. and went their separate ways. but tiffany told friends that wasn't the only contact she had with corey that night. >> she said she called corey from her cell phone around 2:00 a.m. and corey answered the phone. she said when corey answered the phone that corey was asleep. and she asked her what she was doing. corey said i'm sleeping. >> tiffany also told friends she drove to corey's apartment

around 4:00 a.m. and knocked on her door, but no one answered, so she left. >> her statement that she went by corey's house puts her at the crime scene, during the time that corey possibly could have been killed. and that added to that suspicion that she could possibly be involved. >> but when investigators checked tiffany's cell phone records, they made a startling discovery. tiffany didn't call corey after they left the ritz bar. but why would tiffany make up a story like that? >> everybody was talking about the possibility that maybe she was sexually interested in corey. tiffany mentioned to me in a very casual conversation that she had been -- >> tiffany had a real true affection for corey. >> in addition, tiffany told friends things about the crime

scene that had not been released to the general public. >> she was describing the state of the victim's body and the scene without having been privy to photographs at the scene that they thought it was certainly suspicious. >> tiffany denied any involvement in the murder, but when asked to provide a dna sample, she refused. >> the fact that she did not willing give up dna or hair samples led the police to believe she had something to hide. reckon you gotta hotel? reckon, no. reckon priceline express deals will get you a great deal. wherever you...mosey. you reckon? we reckon. vamonos the spring hotel sale is on at priceline.com. save up to 60% on any express deal hotel, when you use code: spring '14. i reckon this is one deal you won't want to miss.

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even though corey parker's friend tiffany smith insisted she had nothing to do with corey's murder, she made untruthful statements about her activities on the night of the murder. she also refused to provide a dna sample. >> she actually put herself at the crime scene in one of her statements. >> but scientists found a surprising piece of information in the blood evidence left by the killer. they found the telltale y chromosome. a "y" chromosome is present only in men. >> we did develop a male profile from a blood sample from the point of entry or exit into the apartment. we were optimistic this could be

from the suspect. >> so tiffany was eliminated as a suspect. >> we believe tiffany was saying things to inject herself into the investigation to make her seem more important than she was. >> investigators believed tiffany learned details of the crime seen from a friend who worked on the emergency crew. police were considered to consider the possibility that corey's murder was a random act, perpetrated by a man with an uncontrollable hatred for women. eventually, police performed dna tests on 38 men, co-workers, fellow students, former boyfriends with no success. >> i was very concerned that they would never solve the case. what i learned from watching other crimes is bad. the longer it goes on, the less likely it is to solve a crime. >> 18 months passed and police continue to work the days,

poring through the file, rereading interviews. to generate new leading, police offered a reward for any new evidence which would lead to a conviction and it generated a lead. some employees from a local steakhouse a few miles from corey parker's apartment called police to report that a co-worker robert denney behaved suspiciously after corey's murder. >> he just seemed to be upset. was crying. had come into the restaurant one day and told them that his child had been killed in an automobile accident in texas and that he needed to get home. >> denney's co-workers responded generously so he could return home to texas. >> after collecting that money, owner of the restaurant went over to give money to his sister. when he was told that robert denney did not have a son that that story was fabricated.

>> and there was something else about robert denney. he lived in the same complex as corey parker. with a direct line of sight into her apartment. >> robert denney told some co-worker about this woman that lived in an apartment below him. and he began to talk about how he would watch her. and even went so far to graphically describe he would masturbate while watching her. >> when police decided to question denney again, his sister told police that he had left the area. >> she had actually kicked him out of the home she shared with her husband because of his odd behavior. staying up all hours of the night his addiction to photography, he told one law enforcement officer that she had

awoken to him standing over her bed and staring at her. >> then police discovered another thing. robert denney's brother was serving life in prison for stabbing a woman 101 times. >> what are the chances of two young men coming out of prison committing the same murders. and was he trying to emulate his brother? ♪ and there's nothing really good around ♪ ♪ turn around ♪ every now and then i get a little bit tired ♪ ♪ of living off the taste of the air ♪ ♪ turn around, barry ♪ finally, i have a manly chocolatey snack ♪ ♪ and fiber so my wife won't give me any more flack ♪ ♪ i finally found the right snack ♪ ♪ ♪ i finally found the right snack ♪ so our business can be on at&t's network for $175 a month? yup. all 5 of you for $175. our clients need a lot of attention.

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18 months after corey parker's murder investigators found robert denney 800 miles away in maryland where he was living with a 52-year-old married woman. >> robert denney had struck up an e-mail relationship with a married woman and eventually had convinced to let him come up there and live with her and her husband. he and his woman had a sexual relationship right under the husband's nose. >> when police questioned denney, they told him they were investigating his possible involvement in a different crime, hopie ining he'd let dow guard. >> they told him they were investigating a potential allegation that he was involved

in aing fight in maryland when they thought he would voluntarily give his dna to prove he was not involved in the fight. >> we would not leave maryland until we got his dna. >> this proved to be harder than investigators anticipated. denney smoked during his interrogation, but always made sure to keep the cigarette butts. detectives offered him a bottle of water, but he wouldn't touch it. finally, they asked him to sign a document saying he refused to provide his dna. we asked him to put the letter into the envelope and seal the envelopes. he refused to seal the envelopes. at that point, basically told us, look, you've tried three times to get my saliva on something. first, the cigarette butt, then the water bottle and now the envelopes. seal it yourself. is there anything else i can do for you? >> so investigators put denney under surveillance at his home and at the computer store where he worked.

he took a cigarette break every 45 minutes. but was careful to keep the evidence. >> when he smoked his cigarettes, he would put out the butts and then put the butts in his pocket so they do not be collected. >> two days passed and investigators finally got a break. just after a brief rainstorm, denney came outside to smoke. >> but this time, he did something different. >> he walked around and then all of a sudden began spitting on the sidewalk, not once, not twice, but six times. >> because of the rain, the saliva was sitting on top of the rain water making it easy to collect. and the barrier helped reduce contamination. >> it was very easy to designate where it was. >> from that point on, it's the same as testing for a hair or

blood stain or seman stain. >> the results were it belonged to robert denney. >> fact that he ever denied being in her apartment made the evidence more incriminating. >> and there was other evidence that implicated denney. the gold-plated lighter found in corey's bedroom. he said it wasn't his. but a former girlfriend told police it was his lighter. >> she was able to identify the emblem on it. she was positive that was his lighter. >> prosecutors believed robert denney was obsessed with his beautiful neighbor corey parker. and monitored her comings and going. he also looked inside her apartment whenever he could.

prosecutors believe denney saw corey get ready to go with her friends on the night before thanksgiving. then armed with a knife and wearing gloves, he entered corey's apartment through the kitchen window. the evidence suggests he hid somewhere, possibly in her closet. and waited for her to return. corey had no hint that anyone was inside and went to bed. that's when denney attacked. but corey fought back. in the process, she pulled out some of his hair which contained his dna. his lighter slipped from his pocket during the struggle. he stabbed her repeatedly. at some point, he cut himself

and bled inside his gloved hand. as he left the apartment through the kitchen window, he left a blood smear on the window sill, providing his dna. robert denney went on trial for first degree murder. the jury deliberated for 45 minutes. >> we the jury find the defendant guilty of murder in the first degree as charged in the indictment. we the jury further find that the killing was done with premeditation. >> since he was only 17 years old, a minor when he committed the crime, denney was sentenced to life in prison without parole. >> he was methodical in cleaning up. he was careful and he almost got away with murder. but for that one drop of blood and hair that he shed that he didn't ever expect to be discovered. >> this girl was a very likable, very intelligent, very beautiful

25-year-old that had a bright future. in front of her. she came from a good family. and had a good social network. had everything in the word to live for. and in one instance, this cold-blooded killer takes her life. up next, a body is burned beyond recognition. >> there was nothing to identify this person. >> unique construction material provides a clue. >> this laster is not like normal plaster. >> i was saying, what is this? is this something i've never seen before. >> but who was the victim and who wanted him dead? >> i have to somehow arti artistically interpret what has changed from the fire. just after midnight one christmas eve, motorists along route 83 near baltimore reported a brush fire just off the southbound lane.