i'm sure that he's got children in his crosshairs. he's not going to stop. he's out there trying to convince you to let him have your children so that he can rape them. homicide investigators faced a difficult question -- was the death of a young woman in a deserted park suicide, or was it murder? an alert homicide detective found a tiny clue in a suspect's trash can. and it was a discarded bandage, a dental expert, and the colossal blunder that revealed a love quadrangle with enough intrigue to go around. 19-year-old devon guzman left her apartment one night and never returned home.

the next morning her roommate, keary renner, and a friend drove all around easton, pennsylvania, looking for her. eventually, the girls found devon's brand-new car in a deserted lot. >> when i saw her -- devon's, you know, lips and eyebrows were purple. and i don't know why i didn't think she was not dead. because nobody really expects that. and i shook her and she didn't answer. i was screaming. i was hysterical. >> devon guzman was pronounced dead at the scene. >> she had sustained a severe laceration in the throat area. >> an empty syringe was found in devon's waistband, although toxicology tests showed no drugs in devon's system. and in devon's hand was a knife. there was no blood on it, and

experts concluded from its size that it was not the murder weapon. >> it was an unsophisticated attempt to lead police in the wrong direction or to perhaps somehow we would conclude that it wasn't a murder. >> the lack of blood at the scene, along with grass and dirt stains on the victim's pants, confirmed what police already knew. >> it's a secondary crime scene for sure. what was apparent to us was, one, she didn't die there. two, she didn't get into the vehicle under her own power. >> devon's body had been covered with her own jacket, which investigators found revealing. >> that's kind of a symbol to us that it was somebody who cared about her. we usually start with the people closest to the victim and then we work outwards. >> devon's roommate, keary renner, was immediately considered a suspect. the two had been lovers. >> devon meant the world to me. and i loved her for who she was. and we were in love because it was real.

>> police discovered that keary and devon guzman had been in a fight the night before the murder. it was so loud that patrons in the bar underneath their apartment heard everything. >> her banging around, yelling. and somebody from the bar goes upstairs to investigate. and they come down and say, well, it's the girls upstairs. >> when questioned by police, keary didn't deny it. >> our fights were more out of the normal like, you know, like we would hit each other or, you know, stuff like that. she would pull my hair, you know, the vodka bottle, throwing it at me. pouring it on her. that's just how we were. >> keary said devon left the apartment after the fight, and she denied having anything to do with devon's murder. investigators decided to take a much closer forensic look inside the apartment.

>> everybody in devon's family already think that i did it. >> i thought it was her. i've got to be honest with you. because she was the rough one. she was abusive towards devon. and so that was my immediate thought that this -- moving her -- i don't know, would do that. lf-serve frozen yogurt franchise. and now you have 42 locations. the more i put into my business the more i get out of it. like 5x your rewards when you make select business purchases with your ink plus card from chase. and with ink, i choose how to redeem my points for things like cash or travel. how's the fro-yo? just peachy...literally. ink from chase. so you can. for over 19 million people. [ alex ] transamerica helped provide a lifetime of retirement income. so i can focus on what matters most.

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keary renner admitted that she fought with her roommate, devon guzman, the night before devon's murder. but keary denied killing her. in their apartment in the shower stall, investigators found devon's car mat. it appeared to have been recently washed. investigators sprayed luminol in the shower stall underneath the mat, and it glowed. it was a positive presumptive test for the presence of blood. dna tests confirmed the blood in the shower stall was that of the victim, devon guzman. >> so our thinking is, well, could the murder have happened in the shower? and could it have started, you know, in the car where there could have been blood?

or she had bled on that when she was transferred into the vehicle? >> keary was immediately brought to police headquarters and given a lie detector test. >> it was terrifying. it was scary. but you know, i really -- i had nobody there that i knew. there was nothing i could do, and i didn't want to give in and say, okay, you're right. because i know i didn't do it. >> the results of the polygraph were inconclusive. >> keary is a viable suspect. we can't rule her out at this time. we have signs of a struggle at her house. we have traces of blood. and we just can't rule her out. >> but investigators found something else in devon's background. devon had another lover, a married woman, michelle hetzel. in fact, devon and michelle had recently returned from a vacation together in the virgin islands. while there, the two made a commitment to one another. >> she told me that they got

married. they go through these things. you know, i gave my advice the best i could from what i saw. but you know, being 19, you can only do so much. you can't chain them to the porch. >> police learned that keary renner wasn't the only one upset by this affair. michelle's husband brandon bloss wasn't thrilled, either. >> it really creates ego problems. it's one thing if your wife starts having an affair with another male. i think if your wife's having an affair with a female, it even creates more problems. and i think that since that was occurring in this relationship, it caused quite a bit of anger between brandon and devon. >> friends told police that devon, keary, michelle and even michelle's husband brandon were often at odds. >> of course, anytime you interject a third person without the consent of both parties, there's going to be a problem there. >> it's four people, not just

michelle and her husband and devon. it was also keary was involved. and keary was the spark plug, if you will. >> in tracing devon guzman's last known movements, a witness told police he saw devon guzman at michelle and brandon's home on the night of her murder. >> i woke up because there was some noise outside that i realized was an argument. the woman i now know to be devon was standing on the doorstep of the house in back of me with two people inside the house, the three of them arguing. i looked at the clock. it was 12:35. >> detectives sprayed the inside of the couple's home with fluorescein, which is like luminol in that it glows when it comes into contact with red blood cells. they found nothing. >> we should be able to detect blood all over the place if this

is where her throat was cut. and we go into the house and we're all over the place, and we're not coming up with anything. >> since dirt and grass stains were found on devon's pants, investigators decided to spray items in the couple's backyard with fluorescein. there on a pool cover and on the nozzle of a water hose were tiny traces of blood. but the blood couldn't be tested for dna. >> it's been too heavily washed off. there's just not enough genetic material there. and when you go to do dna from blood, there's no dna in red blood cells. you have to get it from a nucleated cell like a white blood cell. and there's just not enough there for testing. >> police found another suspicious piece of evidence in the couple's washing machine. >> well, there was a pair of jeans that belonged to michelle hetzel, and there was some water in that. police took the jeans and water. and it tested positively presumptive for the presence of

blood. >> the blood was so diluted, it was impossible to get a dna profile. but in a pocket of michelle's jeans, police found the plastic cap of a drug syringe, the same type of syringe which was in devon's waistband. >> michelle hetzel had worked for a physician in a physician's office, where she may have had access to those types of syringes. >> police now had three suspects in the murder of devon guzman, and all of them had the motive and opportunity to commit the crime. ♪ [ male announcer ] you wouldn't ignore signs of damage in your home. are you sure you're not ignoring them in your body?

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on the night of her murder, devon guzman got into a fight with her roommate, keary renner. she then drove to the home of her other lover, michelle hetzel. >> i really didn't like keary. i thought michelle was the sweet one. keary was the -- the bad one. >> keary renner, michelle hetzel, and her husband, brandon, all denied any involvement in the murder. michelle and brandon admitted that devon paid them a visit around midnight but said she left about an hour later. but based on the forensic evidence, police didn't believe

devon ever left the couple's home alive. >> first of all, no one saw her anywhere other than there. that was the last time she was seen was at that location. >> detective barry golazeski decided to put brandon and michelle's home under 24-hour surveillance. he saw brandon take the garbage out to the sidewalk, and on a hunch, confiscated it since trash is considered public property once it's put out for collection. in the trash bag, golazeski discovered something suspicious, a used telfa pad, commonly used to cover open wounds. >> and it has a unique wound outline on it. you're able to see the entire outline. and it sort of looked like a mouth. >> according to golazeski, they looked like -- like bite marks that's imprinted on these bandages. >> scientists examined the telfa

pad with alternate light sources, which can provide much more information than an examination with normal white light. >> if you look at the gauze pad under white light and you see absolutely nothing, you may go to an alternate light source and find a material which has oozed from the bite mark that does react to the alternate light source. >> under the alternate light source, an image appeared on the bandage. >> the shape of the image on the bandages was elliptical. it had the same type of measurement you would look at when you see a bite mark. and i told them it was very possible this actually was a bite mark. >> investigators now had legal authority to inspect brandon bloss' body. on his left forearm was the clear impression of a fresh bite wound. but whose was it?

the medical examiner ordered devon's body to be exhumed for a sample of her bite impressions. >> well, this is the first time that i've ever been asked to secure dental impressions of a deceased victim, especially one who has been exhumed. i had never done it before. and i'm not quite certain if i know of anybody else in my field who has done it before. >> dr. scanlon took a cast of devon's teeth like an orthodontist does when making braces, then scanned the casts into a computer. using a process called hollow volume overlay, dr. scanlon superimposed computer-generated hollow outlines of devon's teeth over a scale photograph of the bite mark on brandon's arm. the outer rim of the bite cast and the outer rim of the bite mark were consistent. police were convinced that the bite wound on brandon's arm was from devon guzman.

but this was proof that brandon and devon fought. it was not proof of murder. >> i don't think that science in any way inculpates brandon toward a murder at all. what it proves is devon guzman bit brandon bloss, period. >> then police realized something. they had michelle's car in their possession. why? michelle was driving when she and keary found devon's body. and michelle inadvertently pulled up too close to devon's car, so close that her car was impounded as part of the crime scene. >> i don't think michelle hetzel ever dreamed that her car was going to be impounded as part of that search. >> in michelle's trunk, they found brandon's clothing and some rubber gloves. >> we find clothing, a

sweatshirt, jeans, socks, shoes and underwear, and they're all consistent with a male of brandon's build, and there's blood that's evident on these clothes. >> dna testing of the blood on brandon's clothes revealed it was devon guzman's. >> it is direct evidence that shows that the husband, brandon bloss, had contact with this victim and when she was bleeding. you know, it's tough to explain that one. >> brandon bloss and michelle hetzel were arrested and charged with first-degree murder.

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prosecutors do not believe keary renner had anything to do with her roommate devon guzman's murder. the small traces of devon's blood in the apartment shower could easily have been menstrual. and forensic testing of devon's car mat in the apartment revealed the stains were from food, not blood. prosecutors believe michelle and brandon killed devon guzman because of jealousy. >> michelle is married to brandon and he's living with her, but yet devon and michelle are still having a relationship going on, so obviously there's jealousy from multiple people involved. >> prosecutors say michelle hetzel was jealous of devon's continuing relationship with

keary renner. >> there was no question that there was this relationship and there was some jealousies between the girls. they both had a reason to get rid of her. >> and there may have been a financial motive, as well. when devon and michelle went to the virgin islands together, michelle charged the entire vacation on her husband's credit card, including their so-called wedding rings. >> $7,000. well, guess who earned that money? brandon. michelle couldn't keep a job, didn't have a job at the time. she was cheating on her spouse, not with another man but with another woman. >> prosecutors were convinced the murder was premeditated. phone records showed that michelle or brandon called devon on the night of the murder. a neighbor confirms seeing devon arrive around 12:30.

>> cool. >> want to go outside? >> sure. >> at some point the couple lured devon out to their backyard and attacked her. the evidence suggests devon fought back aggressively, biting brandon's arm in the process. but she was no match for the knife. no one knows who actually wielded the knife. the forensic evidence suggests the couple dragged devon's body to the car, leaving grass and dirt stains on her pants. michelle and brandon then drove devon's body and her car to the deserted park just two miles from their home, where they staged the scene to make devon's death appear to be a suicide,

but they made several mistakes. when michelle planted the syringe, she left the cap in her jeans where it was later found by police. the evidence suggests brandon removed his bloody clothes at the park and put them in the trunk of michelle's car. >> i think he actually comes home naked. jumps in the car which his wife had to drive, otherwise we wouldn't find the clothing in her car. >> later, the couple tried to remove the blood evidence from their backyard with a garden hose, but it was discovered with fluorescein. the next day when michelle and keary renner went searching for devon, michelle pulled so close to devon's car that police considered it part of the crime scene. this meant that the police didn't need a search warrant to look inside michelle's trunk.

michelle and brandon eventually turned on one another. brandon said michelle was the one who killed devon, and michelle said it was brandon. >> there was a witness that we called at trial that said about 30 or 40 days prior to this, he had been solicited by michelle that she would give him sex or money or both if he would take out and kill devon, that she wanted to get rid of her. >> in the end, brandon bloss and michelle hetzel were both convicted of devon guzman's murder. they were both sentenced to life in prison. had it not been for the forensic evidence, an innocent person might have been punished, and the guilty may have gone unidentified. >> but for the science we would not have made an arrest in this case and certainly could not have gotten a conviction. >> it was kind of the first time i've ever had a homicide case

where the victim actually had evidence that came from her own mouth in order to convict, you know, her killer. when a 42-year-old married man ran off to montana with a married woman, friends and family called it a midlife crisis. when he disappeared a year later, friends and family called that a homicide. the case went unsolved for 15 years until a civil war buff found more than military memorabilia in the grounds near gettysburg.