lost, lives that have been forever changed. >> that's all for now. i'm lester holt. for all of us at nbc news, thanks for joining us. i can't believe that your baby's lying there lifeless. >> she was everything to me. she was so sweet to everybody. >> state troopers said bonnie had died in a hiking accident. >> they said she fell off a cliff. her mother said they were wrong. >> i was screaming to them, these are defensive wounds. >> no witnesses, no weapon, nothing left behind but a

stranger's dna. >> we no longer have some accidental death. this was a homicide. >> they had no suspect, but for years her mother kept fighting to find bonnie's killer. >> bonnie's mother continues her own crusade. >> then after more than a decade of searching, a phone call. >> they got information there was a match. >> can we get a conviction on just the dna? >> and there was something else, something about bonnie herself. >> it was almost like she knew something. >> good evening and welcome to "dateline." we often see headlines about dna evidence exonerating the innocent. it seems we hear less about how dna is used to track down the guilty. in a story you're about to see, a sample found on a murdered young woman was sent to the national database. 12 years after she was killed, it turned up a match. one profile out of 5 million

matching a man thousands of miles away, but in this case, prosecutors would need more than dna to convict a killer. reporter: many years ago late on a september night, a family in anchorage, alaska, got a knock on the door. >> one of those eerie feelings instantly when someone knocks on the door at 10:00 at night and asked to speak to my dad. >> reporter: 1994, samantha was 12, her brother adam 13, they huddled on the staircase overlooking the front door. >> we heard my dad collapse and scream "no, not bonnie." and i remember thinking, please let her be in the hospital and let her be okay. >> reporter: bonner was elder sister, bonnie craig, 18 years old. >> i remember my dad dropping to his knees crying on the front deck. and that was about the first time i've ever seen that happen. >> reporter: their mother karen was on vacation, was on a sailboat off the coast of florida, four time zones away. it was 2:00 a.m. when she docked, got the news, bonnie

would not be okay. >> alaska state troopers had called and said that bonnie had died in a hiking accident. and you're thinking they're nuts. what's going on? why? why would you say something like that? >> reporter: but it was true, at least that bonnie was dead. it was a hiker who found her body floating in mchugh creek a few miles from anchorage. at first they didn't know who it was, no i.d. on the body. alaska state troopers finally figured it out from the class ring she was wearing. but karen could not take it in. not bonnie, her model child, her conscientious college freshman who she knew was going to school that day, not hiking, miles and miles from home and the university. >> none of it made sense. she didn't drive, so how did she get out there? somebody would have had to be with her. and she would not have missed school.

she absolutely did not go out there on her own. >> reporter: in fact, bonnie's sister heard her get up that morning at 5:00 a.m. and set out on her 45-minute walk through the predawn dark to catch the bus that would take her to her 7:00 a.m. class at that time university. she usually didn't return home until about 10:00 p.m. packing most of her classes into a few days because she had a job at sam's club. >> she was incredibly responsible. >> reporter: responsible and nurturing toward her younger siblings. >> reporter: in part because their parents, mother karen and stepfather gary, had divorced a couple of years earlier. >> she just liked to help us make all the right decisions, and i looked up to her. >> reporter: another brother jason, was two years older than bonnie. >> i tell my kids this all the time, you can decide in the morning when you get up, you can have a good day or a bad day. and she would always choose to have a good day. >> she was incredible. one of those people that as soon

as you start talking to her, you're instantly attracted to her personality. in high school they used to call her tigger because she was bouncy and fun, and so sweet to everybody. >> she was involved in sports. she was coaching the kids in swimming. she started students against drunk driving. she was the very first girl to be on the wrestling team at the high school. >> reporter: bonnie had a serious boyfriend, cameron, who had left that summer to start college at the university of california. >> she used to record herself singing and talking to him and sent him cassette tapes. she was crazy about him, yes. they were madly in love. >> reporter: but now suddenly bonnie craig was dead. at least that's what her mother karen had been told, but as she flew home to alaska, she struggled with denial.

>> i believed flying back that if i got there she might even be at the airport saying, mom, i'm sorry. it wasn't me. it's all just been a terrible mistake. >> reporter: but no, bonnie was not at the airport to meet karen. her body was at the funeral home. >> i only got to see her face. it's just incredibly sad. and you think, my god, it is her. and you can't believe that your baby's lying there cold and lifeless. >> reporter: the next day karen saw her baby again, saw more than her face, and noticed something that seemed to confirm what she already believed -- it wasn't a hiking accident. she called the alaska state troopers. >> her knuckles were broken. so i'm on the phone screaming to them saying, no, you've got to get back. you've got to take more pictures. these are defensive wounds. >> reporter: look again at

bonnie's body, she demanded, look harder. what happened to bonnie craig that september day, screamed karen, was murder. >> when we come back, bonnie's >> i think my mom felt very responsible. >> like i caused this. >> i caused this, you know? they killed bonnie because of something i did. >> was her child's death revenge? ♪ happiness is powerful flea and tick protection from nexgard. nexgard kills fleas and ticks all month long. and it comes in an easy-to-give tasty chew. and that makes dogs and owners happy. no wonder vets love it too. reported side effects include vomiting, itching, diarrhea, lethargy and lack of appetite. see your vet for more information on flea and tick protection you and your dog will love. nexgard. the vet's #1 choice. let's talk about haribo goaloha.s. i can't stop eating this orange one.

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in the autumn of 1994 a suffocating grief descended in anchorage, alaska, and settled on the home of 18-year-old bonnie craig. it was a very bad night. >> it was tough. it was really tough. >> i guess you just don't know what to do after that. how to channel your emotions. >> we were all devastated. >> reporter: once she arrived home, bonnie's mother karen jumped into action, had to find the truth about bonnie's death. and seemed equipped to do so. she was an anchorage reserve police officer, and before that, a local tv reporter. >> karen campbell, anchorage. >> reporter: she told her media friends it was murder, the troopers didn't know what they were doing. >> you're not going to get away >> reporter: she gave a slew of interviews, included samantha in this one. >> she wouldn't have taken a ride, not from a stranger for sure. >> there was nothing accidental about it. >> reporter: but initially it did look like an accidental fall to one of the troopers, the one who happened to be the first to talk to karen. but the others saw the evidence and thought, murder. one trooper at the crime scene

was tim hunier, now retired. >> one thing strange to us, we did find one drop of blood on a leaf at the top of the cliff. >> reporter: one drop of blood. >> one drop of blood. >> reporter: which was found by this man, trooper robert beatty, also now retired. >> i was on my hands and knees and was looking and came across that drop of blood. >> reporter: how big was this drop? >> about the size of an eraser head really. the interesting part about that was that it was a drop that had fallen straight down. >> reporter: indicating to the troopers that she'd been hurt somehow before she got anywhere near the edge of the cliff. >> with it being, you know, five, six feet away from the cliff's edge, it was real apparent to me that, you know, we no longer have some accidental death. this was a homicide. >> reporter: but because there was no sign of a struggle at the crime scene, no weapon, nothing more left behind, it was obvious

this would be hard to solve. so though eventually they told karen they agreed with her, bonnie had been murdered, they wanted her to keep that information secret. fat chance. by then, karen was telling anyone who would listen what she thought, and she was not about to stop. so you spoiled it for them. >> yeah. i did. i got in trouble constantly for me getting involved in the investigation and also -- >> reporter: opening your big mouth to the media. >> yeah. >> reporter: she was troubled by something else, too, her reserve work with the anchorage police department. was bonnie the victim of a revenge killing? >> i was doing undercover work, doing drug buys, and we had done this major bust just beforehand. >> reporter: so in a position to make some people pretty mad at you. >> right.

>> i think my mom felt very responsible. >> rorr: like i caused this. >> i caused u this, ow. they killed bonnie because of something i did. she took that as it was her fault. >> reporter: and so therefore, she had to -- >> figure it out. had to solve the crime. >> reporter: because of guilt of her own possible role and a growing anger of what she perceived as an inept investigation by the troopers, karen began a campaign to keep bonnie's case in the public eye. >> we started handing out flyers, we got bumper stickers made. we started building up a reward. we had bus signs driving all around town. the first one said "who killed bonnie?" >> reporter: and continued doing interviews. >> somebody out there knows what's happened.

and we desperately need to hear from them. >> reporter: and there were lots of tips, which went nowhere, and only ate up the troopers' precious time. they resisted karen's efforts to insert herself into the case and told her as little as possible. didn't tell her about that drop of bonnie's blood at the top of the cliff. >> she was very demanding. i think she felt with her police background, she should be privy to all the information we had. >> the troopers hated me because i just kept pushing and pushing. i wasn't about to give up. i was so fearful that things were being missed. >> reporter: tension grew. troopers rarely returned karen's calls, which compounded her belief the investigators didn't know what they were doing, unwilling to believe and unaware that they were doing a lot. >> we were talking to bonnie's friends and people she went to school with, people she worked with. anybody that had any connection at all with bonnie. we walked the same route that bonnie walked that day to see if anybody was around. talked to the paper girl. talked to people we saw jogging

on the street. we would ride the bus, you know, for a week straight just to talk to all the people on the bus. >> reporter: for a week? >> yeah. to see if they saw anything, see if they heard anything. >> reporter: nobody heard anything. >> no, no one could remember seeing bonnie that day. >> reporter: winter came. karen, consumed by grief, rage, guilt about her undercover drug work, was now a single-minded crusader for bonnie. nothing else mattered. nothing at all. >> it's unbelievable, you know, as the mother, i abandoned my kids and started looking for a killer. >> reporter: it was months before the troopers gave karen the rest of the news about what happened to bonnie. in the last minutes of her life. coming up -- as investigators began looking for possible suspects, they looked first close to home. >> i remember just straight up

asking him, dad, did you kill bonnie? mom you called?

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not the other way around. it was a standoff, tense and unpleasant. karen, the grieving mother, furious at a team of state troopers she did not trust, determined to find out herself who murdered her bright, beautiful bonnie versus detectives who, in turn, did not trust her. and so told her little about

what they knew and what they were learning. but they eventually let her see the autopsy report. that's when karen saw a dozen or so brutal head wound. that's also when the medical examiner told her about one extremely important piece of news, horrifying, but potentially useful. bonnie had been raped as well. and as awful as that was, it left one sliver of hope. the killer left behind his dna. match it and they'd solve the case. so who was it? it couldn't have been the boyfriend, cameron. >> he was down in california going to college. >> reporter: troopers said they looked at karen's work as a undercover police officer and determined that the men in the drug buys were not involved either. but there was one man very close with opportunity who returned home to anchorage from an out of town trip just the night before the murder, bonnie's step-father, karen's ex-husband, samantha's dad.

>> and i remember that being a really unsure, scary feeling. in my mind it didn't make sense. my dad is not and never has been a violent man. so i remember just straight up asking him, dad, did you kill bonnie? >> reporter: do you remember the look on his face when you asked him? >> he was devastated. he was completely devastated. but i just needed to hear it from him because there was so much uncertainty in my life at that point. there was so much confusion that to be able to have him tell me when he was tucking me in bed was all i needed. >> reporter: the dna spoke, too. he was eliminated. but someone did it. troopers set about collecting dna from every man who might have crossed bonnie's path the day she was murdered including some men who worked with her at sam's club. >> we had information that there was one employee there who bonnie complained to her supervisor about. bonnie's phone number off the

sam's club computer and would call her. >> reporter: he was doing a little stalking. >> that put a red flag up right away. >> reporter: dna cleared him. they moved on to a second young man at sam's club whose behavior seemed suspicious. >> they had a meeting at sam's club that morning that she was murdered, and this individual, he did not sign in to the meeting. >> reporter: you went and checked him out. >> we come to find out he was at the meeting, he didn't sign in. others saw him there. we still got his dna and he was cleared. >> reporter: then there was a student, attended an english class with bonnie threw up all kinds of red flags, that is once the teacher read his class journal. >> i met with her, and she showed me his journal that was filled with anger. there was a reference that september 28th was going to be a rough day. and that he was going to be put to the test. >> reporter: that was the day she was killed.

>> yes. and there was a reference to you could see that he was very angry and troubled. he wasn't in class that day. and he came to her later on the afternoon soaking wet and wreaking of aftershave. and he handed in his paper. and she felt like he was nervous at the time. >> reporter: all the signs pointing toward guilt. >> and then he was also at the scene when they were recovering her body. >> reporter: that very day? >> yes. >> reporter: one of the lookie lous, as they say. >> yes. >> reporter: which is often the case with somebody when they've killed somebody, they'll go back and look at the investigation. >> right. >> reporter: what did you think when you heard that? >> i thought this is it. you know? >> i remember instantly thinking bonnie had pepper spray. i wonder if she pepper sprayed him and that's why he had to mask it with cologne.

>> it sounded very suspicious to us. right away, we're just talking about that and jumping on that. find the guy. >> reporter: but the dna eliminated him, too. or so the troopers told karen. >> they said, no, the dna didn't match, and he has an alibi. his step-mom said he slept in that day. >> reporter: did you buy that? >> absolutely not. i said what if there was two people? it didn't have to be his dna. >> reporter: yes. >> he could have been involved and it was somebody else's dna. >> reporter: did you make some noise about that? >> absolutely. >> reporter: but then months went by and years, no match, no justice for bonnie. no peace for karen. for the troopers. then it was 1998, four years since bonnie's murder, the troopers still working the case, when one of them zeroed the on a former city bus driver. >> and he would fill in for the

regular driver on bonnie's bus route. and we just found out from strange things about this guy. he had several reports about him trying to pick up young girls. one of them was the daughter of another bus driver. i'm talking 14-year-old girls. >> reporter: oh, boy. >> he was a substitute teacher but got fired for some of the things he was saying in his classes. >> reporter: apropos of young girls. >> yes. and he left the area and moved down to california. >> reporter: the troopers went looking and found him in davis, california. >> we flew down there to try to talk to him. >> reporter: could this be him, the man who raped and murdered bonnie? could the hunt finally be over? they got his dna. >> it came back that he was the individual involved in bonnie's death or that he had sex with her. everybody was happy, everybody was ecstatic. >> reporter: you got your guy. >> we got our guy. >> reporter: finally they had their man. but what it is they say? don't count your chickens.

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that one. >> reporter: all that was left in the family now in the years after bonnie's murder was the collecting of memories of bits of things that reminded them of how good she was, how thoughtful. like a school paper she was to have turned in the day she died. she read it to her sister the night before, an english exercise in which bonnie wrote about saying good-bye. >> saying good-bye to her friend katie who had died in a vehicle accident. saying good-bye to her dad. her biological father who was never really a part of her life. saying good-bye to cameron as he went away to college.

it was almost like she knew something. >> reporter: something was broken in the family, could never be fixed, of course. but then there was this news, huge news that the dna matched a one-time bus driver who had moved on to davis, california pap the troopers called karen as soon as the results came in. >> you get excited. you think, wow. >> reporter: this is the guy. >> yeah. >> then the bomb hit. >> reporter: the bomb. >> the bomb. they had some new dna system out. they retested it. and turned out it wasn't him. >> reporter: ouch. >> no one could believe it. >> reporter: back at square one. >> back at square one. then dealing with karen again. >> reporter: karen ramped up her campaign to keep bonnie's case in the public eye. >> bonnie's mother karen campbell continues her own crusade to find her daughter's killer. she remains unsatisfied with the investigation. >> reporter: the attention brought in tips. troopers tested more than 100 dna samples. and nothing came of it but frustration.

the case grew cold, as cold as some of the winter nights up here. and four years became six, eight, ten. the case faded from the public spotlight. and so around thanksgiving, 2006, 12 years after the murder when trooper hunyor answered the phone one day -- >> couldn't believe it. the director of the state crime lab contacted me and said that they just got information that there was a match through the codis system for the sample on bonnie craig. >> reporter: they got him. or the system did. codis is short for combined dna index system. a system provided by federal, state and local crime labs. and codis got a hit. >> everybody was happy. >> reporter: the match was in new hampshire of all places. a man in prison for armed robbery back in early 2003. but nobody got around to

entering his dna into codis until late 2006. >> they got a hit the first time. >> reporter: so trooper hunyor flew to new hampshire to meet the man behind the match. his name was kenneth dion. hunyor had never heard of him. their q&a session was taped. >> when did you get into alaska? >> in the '90 some time. >> i started talking to him about his life, where he grew up, where he went to school. how he got up into alaska. >> reporter: so you didn't jump right in and say, we know you killed this girl. >> no, just try to get some rapport with him. basically smoked and joked for a while. you get to travel the state quite a bit? >> a little bit. i went up to denali a couple of times with friends from the military. i made it up there sometimes. >> found out he's fifth degree black belt martial arts, ranked number ten in a fighting competition.

>> reporter: wow. he liked to brawl in bars he said. carried weapons in his car, nun chucks. >> he loved the adventure. >> reporter: he was married at the time of bonnie's murder but later got divorced. >> that's the worse thing i ever screwed up in my life, that marriage there. >> reporter: told you all this? he had to wonder why an alaska state trooper would fly all those miles just to talk to him. he didn't show it. he was civil. answered all the questions. >> just like we're good friends. >> for some reason, i got a bad memory, i forgot things. faces -- i'll forget your name. i've already forgotten your name. >> it's tim. >> tim? i'm sorry. >> no problem at all. >> he told me that he got into cocaine, started using drugs, then everything went downhill. he was basically kicked out of the army and the cocaine became

really a big part of his life and he did some armed robberies to support the cocaine habit. >> reporter: he was in and out of prison in alaska, then in 1996, two years after bonnie's murder, he moved back to new hampshire, where he got in trouble again. and now here he was answering trooper hunyor's next question. did he follow the news when he was up in alaska. >> all the time. >> did you ever meet someone called bonnie or someone like that? >> a pretty high profile case. >> i can't recall. i can't remember. >> reporter: hunyor tried to jog dion's memory. >> i took out bonnie's picture and showed it to him. >> reporter: the man who said he remembered faces insisted he didn't recognize bonnie. but trooper hunyor was watching his body language. >> his leg kept twitching. >> reporter: might he have met her even once, the trooper asked. >> 18 years old? no.

my wife would have killed me. >> reporter: then he got right to the point. >> the sad thing about it, later on that day her body was found at mchugh creek. >> whoa, whoa, whoa. what are you trying to say? >> well, like i said, i'm just down and your name has come up, like hundreds of names. >> why would my name come up? >> that's what i'm trying to figure out. >> reporter: what did you think? >> i thought we had our man. >> reporter: troopers looked up his new hampshire girlfriends. one said he casually mentioned that he could kill someone and get away with it. >> she thought he was blowing smoke. then he also told her i can't go back to alaska because of something i've done. >> reporter: she never asked him about that, but she told the troopers they might want to talk to her sister. >> and the sister told us, yeah, you know, he told me that he can't go back to alaska because he killed somebody. coming up -- bonnie's family learns investigators have made an arrest. >> i am immediately so fearful.

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strange how big events in life can arrive when you least expect them. karen was on vacation again a remote island in the philippines. an e-mail arrived from trooper hunyor, call me, it said.

>> i tried calling him and i kept getting disconnected. >> reporter: but finally they had a conversation long enough for karen to learn one thing, one amazing fact. a dna match. after 12 years they had the man they believed murdered her daughter bonnie. and there on that island, karen felt afraid. >> you would expect that i would be thrilled. no. i'm immediately so fearful that, oh, my gosh, now we know who's done it. are we going to get him convicted? >> reporter: a few months later in 2007 kenneth dion was indicted and extradited to alaska. karen's anxiety only grew. >> i didn't trust the investigation. is the evidence still there? the investigators, the witnesses. can we get a conviction on just the dna? >> reporter: and to make it worse, dozens of pretrial hearings dragged on four more years. >> unbelievably long and

painful. everything's like the day that she was murdered. it's like having everything ripped open again. >> reporter: the trial finally started in may 2011. >> she has 11 lacerations on the back of the skull. >> reporter: it was paul miovas' first trial as district attorney in cold case homicide, and he was worried. >> i went into it with a heavy heart. i knew it would be a task. >> reporter: because the dna from kenneth dion did not prove he raped and killed bonnie, only that sex took place between them. and beyond the dna, the prosecutor had little to connect dion to the murder. there was no weapon, no motive, no witness to the crime. >> we not only had to establish that kenneth dion was the killer, but we also had to disprove that it was an accident and prove that, you know, she had been murdered and she didn't fall off the cliff. >> reporter: his co-counsel jenna gruenstein was an

anchorage school girl when bonnie was murdered. >> i remember very vividly how much this impacted the community. everyone's sense of security when you know that somebody was kind of literally snatched off the street. >> reporter: here in anchorage they were under intense pressure. the courtroom was packed, standing-room only. then on the second day of the trial arc new problem. the defense attorney told the jury in his opening statement that the initial investigation at mchugh creek was inadequate and, in fact, the crime scene video was missing and had been for years. confirming karen's worst fears about the troopers. >> it just made us sick. >> reporter: which made the news that came the next day all the more shock. out of the blue, somebody at the alaska state trooper's office found the crime scene tape. good news? well, you think. but -- >> my concern was that it threatened the trial itself. we immediately took a recess.

a five-day break in trial. >> reporter: the amazing discovery of the long lost videotape could very well be grounds for a mistrial because the defense got it after the start of the trial. for five days the prosecutors researched case law, marshaled their arguments and worried about yet more relays in the trial. but then, good news. the defense attorney decided he would not request a mistrial. back in court prosecutors played the crime scene tape. the public's first chance to see what investigators did the day of the murder. >> i recalled prior to playing the tape my dread on, boy, what's the family going to feel? >> reporter: it was trooper beatty who took the stand when the video rolled. >> this was the first time they've seen their daughter in this horrible position. dead floating in the water. >> unbelievable. unbelievable. i couldn't stop crying, but i made myself watch everything. >> reporter: and as she did, the

most amazing thing happened. >> you would think that for a mother to watch something like that would just be horrifying. >> reporter: you would. >> it was healing. >> reporter: healing? >> healing to me. because i knew then that for 17 years that i hadn't known that they did do the investigation. they did take care and were very confident at the scene. >> reporter: for all those years she accused the troopers of being incompetent at the crime scene, and she was wrong. >> and they were down there on their knees looking for evidence. they're in the water looking for a weapon. >> reporter: that must have changed everything for you. >> it did. >> reporter: a big revelation for her. >> it was, it was. >> i went out and he walked out of the courtroom.

i gave him a hug and told him, thank you. >> reporter: 17 years of anger and tension just popped like that. >> pretty much. within a few minutes. >> reporter: but the prosecution's problem remained. could bonnie have picked up dion's dna from consensual sex? the only solution, let bonnie's own character speak for her. >> i haven't come across anybody else that's been her age and had the level of maturity she had. >> reporter: party girl he was not. >> clearly she was not a party girl. >> reporter: what's more shes was seriously in love with her boyfriend cameron. >> it was clear from every aspect that they were in love with each other. >> reporter: all these 17 years later, even here in court, cameron was grieving still. >> i loved her. >> reporter: so deep in love. but also far too busy, said the prosecutors, to sneak off for

some secret tryst. >> she was working, she was in school, she didn't have time. >> reporter: and why kenneth dion? he was a married man with a newborn, a cocaine problem and a vastly different life. >> they came from two completely different worlds, and there was no reason for the two of them to have mixed together. >> reporter: anyway, said the prosecutors, there was physical evidence of rape. her pants were smeared with grass stains. one of the buttons was undone. she didn't drive. and the place she was killed was miles away. someone must have taken her there. there, where investigators found that one telling drop of blood on the leaf near the top of the cliff. >> is what really showed that she was injured before she went off the cliff, which establishes that she had been beaten. >> reporter: in fact, the state's forensic pathologist testified bonnie's wounds were not consistent with an accidental fall. she had 11 blunt force wounds on her skull but no injuries on her face. and few on her torso.

no blood indicating an accident fall was ever found on any rocks. >> this is a no-brainer. we have this sperm in bonnie craig. there's no dispute about this. >> reporter: this was no accident, said the prosecution. it was rape and murder. this man was about to suggest, maybe bonnie craig had a few secrets of her own. >> it was consensual sex. how many people had a different side to them that was different than what family and friends knew? coming up -- the case for the defense. >> you're saying this young woman -- >> i'm saying that's a definite possibility. >> would the jury buy it? >> we the jury find the ♪ protect your pets from fleas and ticks with frontline plus for dogs

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when bonnie craig's raped and beaten body was found face down in a creek outside of anchorage, alaska, it was september 1994, and kenneth dion was a 25-year-old cocaine addict on the way down a long criminal spiral.

now at 41, he was entering middle age and facing 124 years in prison for rape and murder. >> was bonnie murdered? no. she died accidentally. >> reporter: but not if defense attorney andrew lambert could help it. >> bonnie accidentally fell off the cliff and died. >> reporter: after having consensual sex with your client. >> not necessarily that day. >> reporter: it could have been a couple of days before. >> it could have been. >> reporter: and that was the essence of it, the defense of kenneth dion, that he and bonnie had consensual sex and a few days later she just happened to die in a hiking accident, no provable connection between the two events said the defense. dion told trooper hunyor a few years later that he had never met bonnie, his attorney was now saying the opposite with no evidence of how or when they met. but after all it was the prosecutor's job to prove rape, not his to prove otherwise. attorney lambert scoffed at the

statement that bonnie was too busy or in love with her boyfriend to have a sexual fling on the side. >> you've interviewed thousands and thousands of people, how many of them were really good people that found out had cheated on their spouse, had cheated on their boyfriend and nobody knew? how many people had a different side to them that was different than what family and friends knew? >> reporter: and you're saying this young woman -- >> i'm saying that's a definite possibility. >> reporte but it wod probably be a lot harder to young woman than most other people. >> but you never know. maybe if she met him, got to know him, initially she found him somewhat charming and was maybe enthralled with him and then she never gets to know the history of who he is. >> reporter: is that what he said happened? >> you know i can't answer that because that's attorney/client privilege. >> reporter: in any case, bonnie's death was consistent with an accidental fall, his defense expert testified.

>> when the body tumbles, we don't know how it tumbles. injuries can occur in micro seconds and not leave blood on the rocks. >> reporter: what's more, not one person could place kenneth dion with bonnie or at the creek that day. >> there's no witnesses to say that they saw ken and bonnie together that day. >> reporter: yeah. >> there were no witnesses placing him near her, along her route. >> reporter: the case went to the jury in mid-june. it was not for long. karen and the family were on their way to do a tv interview and -- >> as i'm pulling up to the interview, i sigh the cameraman and the reporter taking off. and they circle around. they said, the jury's back! >> reporter: the jury deliberated so fast, just several hours, they thought it had to be guilty. >> it was incredibly exciting because we knew that it was going to happen. we just were dying to hear the words. >> reporter: and when you did. >> we the jury find the defendant, kenneth dion, guilty

of murder in the first degree as charged in count one of the indictment. >> praise god. >> it was like the weight of the world was lifted off our shoulders. he's guilty. amazing, amazing. >> ken dion did not kill bonnie craig and did not rape her. >> reporter: are you telling me that you believe your client is innocent? >> i am. >> reporter: you don't think he committed this crime? >> i don't. >> we're asking for the maximum sentence. >> reporter: at the sentencing this past october, as the prosecutor argued for 124 years, the maximum sentence and no chance at parole because dion hadn't shown any sign of remorse -- >> mr. dion, as the family has pointed out, has never taken responsibility for what he's done. >> and i never will because i didn't do it! >> and that answers your question, judge. nothing further. >> reporter: kenneth dion, as if on cue, denied it all. the judge gave him the maximum but also the chance at parole when he's about 80.

for now, dion's appealing the is it possible he actually didn't remember doing it? >> i struggle with that. is it possible that his protestations are sincere in that he had an episode in his life that he's either blocked out or for some reason can't recall based on what was happening in his life at that time. >> reporter: cocaine puts holes in your brain, they say. >> it does. >> reporter: amazing, this is a man who got away with murder for a long time and would have completely, scot free if it hadn't been somebody put the dna into codis. >> that's really remarkable. >> reporter: which is, it turns out, the subject of karen's new campaign. she is now on the side of the alaska state troopers and other law enforcement agencies trying to persuade every state to enter dna into codis, the national databank, upon arrest. after her push for a change in alaska, the state now enters the suspect's dna once arrested for a felony just as it records mug shots and fingerprints. >> right now there's only 26

we need all of them to collect it. dna doesn't lie. you get to the truth so much sooner. it saves money. it saves lives. >> reporter: samantha channeled her grief. she's a 911 operator now. >> 911. what's the location of your emergency? >> so when you have somebody on the other end of the line who is calling in because they just found out that somebody had died and they need to know what happened, i feel that pain. i know that pain. >> reporter: as for bonnie's older brother jason, father of three sons, his mission is more personal. >> it changes the way i raise my kids. spend more time to make sure that they're understanding why things are done certain ways or what builds character, what really is important in life. >> reporter: sounds like you're trying to grow some more bonnies. >> maybe. >> reporter: you miss her a lot, don't you? does the ache ever go away?

>> no. >> she was kind to everybody. and that's why it was so shocking that anybody would harm her because she would never harm anybody. she was such a sweetheart. >> that's all for this edition of "dateline." >> i wanna know what happened to my mom. i just wanna know why. why they let it go. why was she forgotten about all these years? i'm not gonna stop until someone