operator: 911. what are you reporting? narrator: clay starbuck and his children say he's innocent. but in june of 2013, he was convicted of first-degree murder and sentenced to life without parole. even detectives admit that as brazen as this crime was, clay came very close to getting away with murder. in all of my years of investigating crime scenes, i've never seen someone take so much time in a crime scene to pose the person, to dispose of evidence. sparks: the forensic evidence definitely helped this case because the dna that they were able to gather helped seal it that it was a male that had killed her and it was a starbuck male that had killed her. if she had not made that 911 call, as brief as it was, the authorities never would have narrowed the time frame. they never would have been able to eliminate suspects other than clay.

she truly helped them solve this crime. ♪ narrator: up next, a sexual encounter goes horribly wrong. she fought back. she gave us the evidence we needed. narrator: the victim pays with her life. she didn't deserve to die, not that young, not that way. narrator: investigators think they have solid information on her killer, but a brand-new piece of forensic technology upends the investigation. this was completely different from what they had expected. ♪ ♪ ♪

narrator: lake charles, louisiana -- one of america's gateways to the gulf of mexico. it's a tight-knit, blue-collar community where people work hard and live easy. mcgee: i was born and raised in lake charles. it's about 100,000 people. it's a diverse community. many of our families work at the petrochemical industry and at the local casinos. narrator: but as thanksgiving approached in 2009, the peace of this bayou boomtown was shattered when shortly after dawn, a young woman was found dead off a secluded road just out of town. whoever did this was mad and angry, and it was a brutal murder. mcgee: this homicide was overkill in every sense of the word. someone was very angry when they killed her. narrator: investigators from the calcasieu parish sheriff's office processed a scene of uncommon violence.

the victim had been beaten beyond recognition. she had on a blue jean skirt and it was twisted to the side. her bra was pulled open and her shirt was down. she's all cut up. so she did struggle. it appears she ran out of her flip-flops because they're in two different places, and her panties are near one of the flip flops. narrator: problems presented themselves straight away. the area was so isolated there were no streetlights, which meant no witnesses. there was no murder weapon at the scene. the victim had no identification. but the killer did leave some clues behind. we had numerous pieces of evidence from the scene, including a candy wrapper. there were bloodstained rocks that were swabbed at the scene, and the swabs were submitted. narrator: the autopsy revealed the victim died of blunt force trauma to the head, and the motive appeared to be sex. i think that she got picked up by this suspect. i think however it transpired,

he wanted to have sex, she didn't, and she fought for her life, and unfortunately, he ended up killing her. but i do not think any sexual activity actually happened, and i believe that's because she fought him off and did not want to. narrator: in attempting to identify the victim, investigators got a possible break. she had a distinctive tattoo of someone's name, and since tattoos are an identifying feature and lots of people have them, many jurisdictions keep a file of offenders' skin art. we photograph them and we put them in our computer system. her tattoo was very unique, which narrowed it down to be just her. then with her book-in photograph, her driver's license, we were able to identify her. narrator: the victim was 19-year-old sierra bouzigard, a young woman with a troubled past. bouzigard: she had a rough time growing up. i wasn't the mother that i should've been for her.

i wasn't there for her when she needed me. when i found that she wasn't alive, it's like, "why her? why not me? should've been me." narrator: sierra's lifestyle might or might not explain what looked like a sex crime. mancuso: she was using prostitution to help support her drug problem. i don't want to use the word "gypsy," but she really just kind of lays her head wherever she can find a spot. mcgee: sierra lived a high-risk lifestyle. her background may have affected me a little different than it does others, because i grew up in a community where people ended up like sierra. and so i saw myself in sierra, and it became more personal to me. narrator: and now investigators got another possible break. sierra had been released from jail on a minor drug charge just three days before her murder. mcgee: so her background helped in a way and hurt in a way. it helped because we only needed

to fill in the blanks of 72 hours. she had only been released from jail for those 72 hours, so we backtracked that way. narrator: but where that backtracking took police threatened to stop the investigation dead in its tracks. ♪

narrator: even though sierra bouzigard's murder appeared to be sexually motivated, no dna was recovered from her rape kit. but thanks to sierra, the killer left his dna behind. she apparently fought off a sexual assault before being killed. the coroner was able to obtain a dna sample from under the fingernails of sierra. narrator: this meant the killer would likely be scratched up. even better for investigators, this dna profile matched other evidence at the scene. quaal: there was a profile obtained from a candy wrapper.

that was a full profile, what we call a major-minor. the profile on the candy wrapper was a great quality profile. narrator: investigators knew that killers who resort to the kind of overkill seen in sierra's murder have usually killed before or have at least committed violent crimes, so they were confident they'd find a dna match to their killer in codis, the national dna database. well, i think we're going to solve it immediately. i think, "okay, if we put this in codis and we get a hit, then case solved." narrator: but it was not to be. despite the high quality of the killer's dna profile, there were no matches. i was very aware there was not a hit in codis. that was very frustrating for us, and i know it's frustrating for the detectives, as well. ♪ narrator: now investigators backtracked sierra's final hours, and true to her freewheeling lifestyle,

this led in some unexpected directions. mcgee: we knew that she attended a party with some hispanic males, and found some friends there, and liked some of those guys. narrator: those hispanic men, more than a dozen in total, turned out to be workers who had taken temporary construction jobs and shared a house near the murder site. mancuso: these people are undocumented, illegal aliens, and so we have nothing to go on other than if they're telling us who they are, if that's who they are. we got nothing. narrator: the men freely submitted their dna. none of their profiles matched. and they had more bad news for investigators. one of their group fled town right after sierra's murder. ♪ mcgee: we believe that the worker was headed back to mexico, and he had an eight-hour jumpstart on us. you have to realize we had to identify sierra and put the pieces of the puzzle together

before we even ended up at that home. so he had a good little jumpstart on us. narrator: and he apparently made it back over the border. for those seeking justice for sierra, this was a disaster. mancuso: we were continually working with the fbi and the u.s. marshals to try to find this guy and bring him back to get him here, at least to get a dna sample and question him about what he did that night and what was going on that night. narrator: but they didn't know who he was or where he was and had only a vague idea of what he looked like. the case stalled for nearly six long years. yeah, that frustrated me a lot. narrator: investigators shared the family's frustrations. they had the killer's dna, but with no other clues, it was all but useless. mancuso: i think any time any murder occurs and you're trying to solve it and you can't, it's very frustrating. i always felt like we were going to solve it because we had dna.

mcgee: we can't put an identity with this dna. we had all kind of great ideas, but none of them panned out because nobody is matching. quaal: this case was worked on every aspect harder than any other case i'm aware of, at least in this area. narrator: there was, however, one thing they had not tried because the technology was just being developed. quaal: it was really hard to believe that this would be able to work. i did not think that you could create a picture from dna. narrator: but was it science or science fiction? ♪

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can katie sleep over tonight? sure, honey! this generation is so dramatic! move with xfinity. narrator: sierra bouzigard's murder had all the earmarks of a random attack, a stranger-upon-stranger killing that are always the hardest to solve. mancuso: normally we get four to six homicides a year. very seldom do we have a whodunit. normally it's domestic in nature or a drug deal gone bad.

very seldom is it just a random act of violence. in this particular case, that is exactly what this was. narrator: as the years pass since sierra's murder, detectives in calcasieu parish, louisiana, refused to let the case go. mcgee: it was so frustrating. i lived and breathed this case. i just felt so drawn to it. so we were open to everything that everybody had to say -- every tip, every idea. narrator: and that search for something new turned up a possibility when dna analyst monica quaal saw a web seminar from a cutting-edge forensics company called parabon nanolabs. quaal: we were contacted by a neighboring agency saying that they had some interesting science that a new agency was doing, and they were interested in sharing with us. narrator: parabon claimed that they could take dna evidence to a completely new level. they said it was possible to put a face on unidentified dna,

that the human genome combined with massive computer power could actually tell investigators what someone looked like just from their dna. detectives believed sierra bouzigard's killer was an undocumented mexican worker. but there was no clear description of the suspect. monica quaal raced to tell her fellow investigators that this new technology could provide that description. i really think that she's crazy. she was like, "you just have to have faith in me." i was like, "i have faith in you, but this just kind of seems like magic." and she's like, "no, it's gonna work." and so she convinced me and then we convinced the sheriff. narrator: parabon got the unidentified dna sample from sierra's case and put it through a process they call snapshot. snapshot is a way to take that dna and ask it questions. okay, if we don't know exactly who this person is, do we know his ancestry? can we say something about eye color, hair color, skin color, freckling, face shape?

can that information at least help the police narrow their investigation and be more efficient? and the answer is yes. narrator: genetically speaking, human beings are remarkably similar. it's only a small portion of the human genome that makes us different from one another -- eye color, hair color, facial shapes. quaal: the genome is so big. greytak: we're talking about 3 billion pieces of information. if we looked at your dna and my dna, we might differ at a few million spots. but those tiny differences are the reason that those two people look different. narrator: parabon has assembled a vast library of known genetic information. they have the dna of thousands of volunteers, and courtesy of a 3-d photographic process, they also know exactly what each of these people look like. armentrout: traditionally, a 3-d camera rig is used.

multiple cameras have to be synchronized. they have take the picture at the same time and just know their locations. if you have that, then you can use mathematics to actually recreate the three-dimensional shape of someone's face. narrator: snapshot uses those photographs and that dna to create a library of known genetic information. then the unknown, so far unidentified dna, is cross-checked across that library by computers billions of times a second. the result is a high-tech prediction of how the unidentified person might look. it's important to remember that the composite is not a photograph. narrator: these composite images were created by snapshot using dna and genetic data from their library. they reveal not just ethnicity, but specific facial features. it's intended to be a description of a person, so it's essentially a summary of the prediction information,

but that information is just coming from the dna. narrator: of course, you can't tell how a person parts their hair or if they have tattoos or scars or their exact age. but in dozens of cases, snapshot has used dna to put a face where none existed before. if you reflect on what we're doing, it shouldn't sound like science fiction. narrator: the chief suspect in sierra's murder was a mexican construction worker. but investigators were in for a shock. this was the image snapshot created of the man who killed sierra bouzigard. he wasn't hispanic. he was caucasian with blue eyes. this meant they had been looking for the wrong man for six long years. mancuso: it was a step-back moment. it was literally, "holy crap, what just took place here?" we're not even looking in the right direction. mcgee: when you first see that sketch, it just -- it's unbelievable, and you're like,

"have we wasted all these years going in this wrong direction?" it was very different from what we were expecting. we predicted that this was a caucasian male, fair skinned, blue eyes. very, very different from the hispanic male description that they had previously been looking for. narrator: detectives could have viewed this as a setback for their investigation. instead, they viewed it as an opportunity. we literally started over from scratch right there at that point, and it was a new investigation. armentrout: it's always nice when the dna can help redirect an investigation. this is an example of when that happened. narrator: but could the new investigation find this man? ♪

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released this computer-generated likeness to the media. created solely from unidentified dna, they were hoping this could predict what sierra's killer actually looked like. there were concerns, but we still wanted to blast it out to the community, hoping that somebody would call in. and we were fortunate enough to have several tips. narrator: one of those tips was highly unusual. a woman said she got a strange call from her now ex-husband right after the parabon image was broadcast on tv. mcgee: he called her that day and said, "remember that i was with you that night." and she was like, "what night?" and he said, "the night that sierra was killed." and she said she went back to that night in her head and remembered that he left to get cigarettes and should have only been gone for about 10 minutes. the convenience store was right around the corner, and was gone for many hours. his name was blake russell, a 31-year-old with a history of petty crimes. his ex-wife told detectives

it was possible blake could be their man. mcgee: she said each time they would have sex, it was like rape, like that's the only way he knew how to do it. sierra would have done it for money, but i don't think he wanted to pay her. narrator: investigators were stunned. blake russell bore a remarkable resemblance to the dna image created by parabon. i just couldn't believe how much he actually looked like this sketch. to this day, it still surprises me that it all worked as seamlessly as it did. i couldn't believe from a dna sample they could come up with this picture. it was a happy day here at the sheriff's office, i can assure you. narrator: but just because blake russell looked like the parabon image didn't prove he was sierra's killer. in fact, this technology was so new, so untested, it wasn't even legally sufficient to get a search warrant. we felt like he was our best suspect, and it was just gonna be a problem trying to get his dna.

narrator: but detectives had something going for them. blake had no idea they were looking at him. mcgee: so one of our guys went into a local bar, had a beer with blake russell. he actually had this crazy story about how he was going to make a beer bottle christmas tree for his grandmother and asked blake if he could have the beer. blake gave him the beer bottle. he walked out and brought it to monica. the dna test results left no doubt. the dna from the beer bottle matched the dna from under sierra's fingernails and from the candy wrapper at the crime scene, incontrovertible proof that blake russell was sierra's killer. quaal: i remember being in total shock just because we had been looking for that profile for so long. narrator: russell lived down the street from the group of undocumented workers. investigators believe he went out for cigarettes that night, saw sierra walking from the party to a friend's house,

and offered her a ride. he then attempted a sexual advance, which sierra either rejected or she may have asked for money. russell exploded, and sierra found herself fighting for her life. police believe russell used a tire iron from his car as the murder weapon. sierra scratched him during this altercation, creating the microscopic dna evidence that would ultimately produce the virtual image and land russell in jail. bouzigard: i'm proud of her. i knew she was a fighter. i knew she was, and she got that from me. she got something good from me. armentrout: the dna was there at the crime. it's a matter of interrogating the dna intelligently and rendering the output in a fashion that's useful to the police. narrator: in july of 2017, blake russell was charged with second-degree murder. while awaiting trial, he hanged himself in his jail cell,

a development that brought no satisfaction to sierra's family or to investigators. they wanted the case to go to trial. they have no doubt this revolutionary piece of dna technology would have put blake russell behind bars for a long, long time. quaal: the nice thing about this is that it will create a picture of this person, and not based on someone's memory, but actually based on the dna in the case, which doesn't change. mancuso: it was everything. it was her fighting and giving us the evidence. it was the coroner swabbing the dna. it was our analyst monica running the dna and staying on it. i'm just very proud that we have people that are dedicated like monica who are willing to challenge new technology. to challenge new technology it's still sometimes unbelievable how awesome technology and scientists and how we were able to solve