two winters passed here in the colorado rockies between the untimely demise of stephanie roller bruiner and the district attorney's attempt to pin it on dale bruiner. he steamed in silence about the lies against him. >> the lies are really tough to take. you're just like, really? >> during the trial, he continued to live here all alone in the family house by the blue river, working with his attorney in the effort to clear his name. robert bernhardt was his attorney, a man not at all impressed with the police investigation. >> their position was, i think dale is the easy guy, the worst pieces of investigating i've ever seen in my career. >> dale and his attorney told us

that despite a show of interviewing other suspects, the police quite clearly had made up their minds the very day she disappead. >> the police came to my house. i don't know what the exact first thing he said but he goes, did you kill your wife? and i was just stunned. >> the police didn't seem to want to believe what he told them about how happy he was that last evening, discussing new possibilities, a fresh start. when around 9:00 p.m. their daughter came into the bedroom to ask for help with her homework. >> when she came into the room, we were laying on top of our bed, cuddling. >> nor he said did the cops seem to want to believe his explanation for not reporting stephanie missing until morning. more than nine hours after she walked out into that frigid night. >> why would he? if he was aware of the fact that she was having an affair, he probably assumed that she went to her boyfriend. >> the last thing i was going to do was make waves. just do what you got to do. >> they made such a big deal of the fact that dale didn't join

the search for stephanie, even though -- >> i called the police. and they told me stay home in case she comes home. >> so by the time dale's trial began in the summer of 2012, he and his attorney were ready for evidence that they knew was only circumstantial. questions like this. >> even the way she was beaten on her head and strangled the way she was strangled, it's a very intimate crime. it's the sort of crime that husbands commit when their wives are about to leave them. >> or should i say their boyfriend? >> or boyfriends. yeah, well, there you go. >> that was point his lawyers wanted to make in court, that police and prosecutors had unfairly brushed off the possibility that stephanie's new soulmate or his wife had anything to do with it. that would be ron holthouse. >> when everybody found out that stephanie was missing, did any police officers come and visit you at work or at your home that day? >> no, they did not. >> and didn't ron's wife cindy have a motive?

>> and i said something like, i don't know where she is, but i hope she rots in hell. and i'm very sorry i said that. >> of course, dale and his attorney knew the prosecution would make a big deal of that restraining order stephanie took out after dale spanked their son, but her decision to ask for that order, said dale, sprang from her own confusion, the affair, the chaos in her life. >> i believe she built a fake little world where i was the bad guy. >> but was stephanie ever worried that dale might get violent? hardly, said the defense. why else would she ask the judge to delay the order until after their little family holiday? >> the judge said he had never seen someone have a restraining order but then have them say, well, don't enact it yet. not until next week. >> and why would she go away on a yoga retreat and decline this friend's offer to babysit? >> can i take care of the kids? she said, no, they're fine with

>> and that's because she knew dale wasn't a threat to her. he wasn't a threat to those children. >> remember how the detective found the house unusually spotless two weeks after the murder? it was, it turned out, family and friends who cleaned up, apparently because dale was paralyzed by grief. >> dale walked into his walk-in closet and half the stuff is stephanie's. and he comes out and he's just crying and he's like, i got to get this stuff out of here. >> so it's clearly a rush to judgment, a sloppy investigation, said the defense, by the detectives who bought the holthouses' alibi too easily, and forgot about the guy who robbed a bank a few hours before stephanie disappeared. >> you had no direct evidence of mr. bruner assaulting his wife? >> correct. no direct evidence of mr. bruner murdering her. >> of course, had dale taken the stand, he would have ho

answer some stubbornly uncomfortable facts. and this question that hung over the defense table like a cloud. >> you loved your wife. you loved her a lot. but in that moment of extreme rage when she was leaving you, you killed her, you strangled her and then threw her body in the river. >> it's so not true. >> the theme of the prosecution was that you were an abuser and that it was -- >> it's beyond so not true. it's just not true. they painted quite a picture, though. >> oh, yes. they certainly did. with the help of a woman whose message in a way came back from the grave. coming up, stephanie speaks. >> i'm here. asking for help. >> and so does another voice from the past. >> he had a look on his face that i had never seen or recognized before.

i'm sitting across from a man who may be telling me a true story, who may also be living with the knowledge that he hit his wife on the head and strangled her and put her in the river and that's where she died, and you have to live with that secret for the rest of your life. >> fortunately, i don't have to live with that. that i don't have to live with. >> what dale bruner would have to live with would depend on the

and whether or not then prosecutor mark hurlberg can persuade the jury without physical evidence that dale killed his lovely wife in a fit of blind rage. >> i think dale bruiner strangled her, i believe she was dead, and he takes her and dumps her into the river. >> so what did happen on the night of the murder? the prosecutor called a child to start the story. dale and stephanie's eldest daughter, the girl who walked into their bedroom at 10:00 p.m. >> at 10 years old, she could say what happened with specifics. >> out of the gaze of the jury, she told the court she heard her parents arguing, not cuddling, as dale claimed. after which, remember, dale claimed stephanie went for a walk to clear her head. but at temperatures well below freezing? you've got to be kidding, said the prosecutor. >> his wife goes for a walk and he wouldn't call anybody until eight or nine hours later, ten hours later?

>> which by itself didn't mean dale was guilty. but this is where some of those secrets began to spill out. the terrifying secrets of a fatally troubled marriage. like the one stephanie told this friend after that spanking incident when she applied for a restraining order. >> did she express fear to you at the time? >> yes, she did. she looked at me and she said, he just sees red. he gets so mad that he goes into a red zone, and he doesn't even know what he does. >> and so, said this friend -- >> she was afraid to get a restraining order against dale because he had already threatened to harm or kill her. >> that threat from dale was years earlier, but stephanie had never forgotten how terrified she was. she told the story to her friend jennifer just before the murder. >> he strong-armed her into a corner, choking her, threatening to hit her.

he stopped short of hitting her, but he did. and there was another time he threw her on the bed and put his knee on her pregnant belly. >> how often would this happen? >> you know, there may be three of those -- two or three, i don't know, about those incident that is she talked about. >> then there was leah aiken, long-time friend of dale's, who told the court about his reaction when stephanie told him she was in love with another man. >> he just wanted her dead. you know? maybe she would have a heart attack or get hit by a car. i kept telling him to stop talking like that. >> but did dale really mean that? could he be truly violent? consider this woman, said the prosecutor, an ex-girlfriend from dale's past, a woman named jodi, who told the jury and us a strange tale of what happened one night when she lived with dale 20 years ago. >> he hadn't come home for dinner one night and had said he would be home. >> you called him on it. >> he came home, we argued about

yelling at me. he pushed me down onto the floor and put his hands around my neck and said, if you ever say or do that again, i'll kill you. he had a look on his face that i had never seen or recognized before. that was the most scared i have ever been in my life. >> and even though that was a long time ago, said the prosecutor, it told a terrible tale which, sadly, is as old as time. dale, he said, was a man sometimes overcome by rage, and his m.o. was to go for the throat. >> she was strangled so hard with such force that it broke a bone in her neck. >> and then the prosecutor introduced his bombshell. stephanie herself on tape. six weeks before her murder, stephanie begged a judge for that restraining order. and now in court, her recorded plea was a voice from the grave.

years ago, but, you know, with a hand on my throat. didn't squeeze it, screaming in my face, i will kill you if you leave. that i've never forgotten. >> her sister was sitting in the courtroom, listening, and was overcome. >> and that was when we lost it. because it was feelings of, oh, my god, and she's crying. >> it was as if stephanie was testifying in her own murder trial. >> i would so love to talk to him about it and say can he leave or can he get help. and i just think that would go really bad. so i'm here asking for help. and i'm going to end up getting a divorce because there's no way i can go back. >> only she did. finally, this domestic violence expert weighed in. >> when a victim is attempting

left a relationship, it is by far the most dangerous time for a victim. >> but what was the trigger that, according to the prosecution, set dale off? the answer, he said, may lie in an unfinished e-mail stephanie was writing to the other man, ron, just before she was murdered. though dale denied he knew what she was doing -- >> i honestly didn't know. i had no idea. >> -- the prosecutor said dale must have seen her writing it, an e-mail begging ron for another meeting because she couldn't accept the idea that her new love was leaving her. >> i think dale bruner got angry at that and hit her with something. then he strangles her, believes that she is dead, she's probably unconscious at that point but she is not dead. takes her to the river and dumps her in the river. >> the jury stayed out four hours. >> the court has reviewed the verdicts. >> it was kind of early, which is always worrying. >> dale er

>> you're just trying to maintain and not just melt. so you prepare yourself to just breathe. just breathe. >> and then there it was. >> we, the jury, find the defendant dale bruner guilty of murder in the second degree. >> dale bruner was taken away in handcuffs. >> it is a perfect storm. i'm going down with the ship. >> stephanie's friend jennifer was driving when the verdict came in. >> i was in my car parked on the side of the road, crying like a baby. >> and like others who knew stephanie, she wishes now she had taken her friend's secrets more seriously. >> i beat myself up over it every day about how i should have done this or should have done that.

one deadly flaw. >> a lot of stephanie's close friends and family didn't even know what was going on, and i knew of a couple events over the years, and let's say it was only two, it only took three and she's dead. >> and so, say her friends, take some advice. heed the warning. don't hide the secret. >> that's why i'm talking about it now, and hopefully just one woman would have the courage to stand up and say, i'm being abused, i'm living in fear, i'm living with secrets, and i need to stand up and be bold. >> that's all for now. i'm lester holt. thanks for joining us. breakthroughs in dna technology. and that finally gave police a suspect.

who it was shocked everyone. >> reporter: coming up -- it's always the husband or the boyfriend, right? but that didn't seem to be where this investigation was going. >> the headline here is stephen cooke is not the guy. >> right. >> when "dateline" continues. i love you, couch. you give us comfort. and we give you bare feet... ...backsweat and gordo's everything. i love you, but sometimes you stink. ♪ new febreze fabric refresher with odorclear technology... ...cleans away odors like never before. because the things you love the most can stink. and plug in febreze to keep your whole room fresh for up... ...to 45 days. breathe happy with new febreze. with tampax pearl. you get ultimate protection on your heaviest days and smooth removal for your lightest.

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>> reporter: as the years rolled by, the heidi bernadzikowski murder case got colder and colder. detective al meyer was frustrated. he was promoted out of homicide but he never forgot the case. >> even when he was in another unit, he would come back up to the homicide unit and go through the file. >> never got squirreled away, huh? >> no, no. never. >> yeah, he never -- he never let it go. >> reporter: heidi's grieving family was trying to get on with their lives, remembering o

her birthday by eating her favorite shrimp alfredo, but family events were hardly the same. >> you couldn't fully enjoy these special occasions because you're always painfully aware that -- >> you had an empty chair. >> you got an empty chair, that she should be there and she's not there. >> reporter: heidi's boyfriend stephen cooke was trying to move on with his life as well. he married, had a child, and landed a steady job with veterans affairs. >> he's got a normal life for the first time in a long while, huh? >> he does. things are looking pretty good for him. >> reporter: then, in 2011, 11 years after heidi's murder, meyer rejoined the homicide unit and once again cracked the file. this time, he and veteran baltimore county detective gary childs got an idea. >> dna technology had progressed and we knew now that there's a possibility that heidi's fingernails may contain some physical evidence. >> so what's the thought, let's run it again, see what happens

>> reporter: to their surprise, the criminal database spit out a match. >> we got a dna hit. i couldn't believe it. >> reporter: but the hit wasn't for anyone in heidi's known circle, even in her geography. it was a name completely off the radar from a state over 1500 miles away. >> they tell me it's this guy, alexander bennett, from colorado. >> colorado? >> and i'm, like, wow, that's not good. i'm hoping it's going to be somebody from baltimore, somebody that would be local. >> did that name mean anything in heidi's circle, alexander bennett from colorado? >> never heard of him before. >> absolutely not. >> no. >> reporter: baffled detectives started to dig. they called the colorado authorities and learned bennett was an unlikely suspected killer. in his early years, he showed promise as an opera singer. performing recitals and winning a scholarship to the prestigious

after moving back to colorado though, he'd gotten into some small-time trouble. but then he did something just plain crazy. >> he's a pretty talented guy, but he had some issues with the people he hung with and one of these issues was with a friend of his named grant lewis. >> reporter: in 2003, bennett and grant lewis had been arrested in a doozy of a scheme. they'd called 911 and said that a friend of bennett's wanted to bomb the courthouse. but they went further, building a real bomb and planting it in his house. the bomb squad was dispatched and that friend hauled down to the station for an interview. >> they're grilling him pretty hard because that's kind of a serious crime. one of the detectives ultimately lets him listen to the 911 call and he recognizes grant lewis' voice. >> so it's not all muffled or disguised or -- >> no. no, it's just -- >> he said, that's -- >> -- that's grant lewis, i know him. >> yes. >> reporter: within days, lewis and bennett confessed to the whole thing. building the bomb, breaking into

the house, even uploading bomb-related materials to the buddy's computer to ensure he'd be arrested. also that friend who bennett said beat him up wouldn't notice that they'd made off with his jeep. >> so it's all a hoax, this elaborate caper to plant an explosive device in order to get him out of the house so they can steal the car? >> yes. >> my word is harebrained. what's yours? >> yeah. double harebrained. >> reporter: alexander bennett was sent to prison and required to give dna. now, years later, that dna was tying him to heidi's murder back east in maryland. for baltimore prosecutors garrett glennon and matt breault, the dna was an enticing lead but far from definitive proof. >> it was enough to say it looks like it came from him, you know? but we can't say it's definitively his. so there was more investigation to do. >> reporter: so, the detectives went to work, looking for another connection between colorado native alexander bennett and the maryland murder.

all the usual computer searches failed, but when sergeant meyer had the maryland state police mine an offline database -- >> i get this phone call from the trooper and he tells me, i've got alexander bennett, somebody running a wanted check on him march 30th of 2000. >> a maryland officer. >> in maryland. i'm thinking, holy cow. >> reporter: three weeks before heidi's murder, an officer had spotted alexander bennett walking down a baltimore highway. >> when a wanted check is run by a patrolman or an officer that check remains in the computer forever. >> how important was that? >> incredibly important. >> reporter: detectives meyer and childs hopped a flight to denver. it was time to meet this alexander bennett. >> coming up -- >> a suspect's story, a surprise to even these experienced detectives. >> that's why -- it is strange.

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>> reporter: in january 2012, two baltimore county detectives flew to denver, colorado. their mission -- to track down alexander bennett, the man whose dna had been tied to heidi bernadzikowski's murder 11 years after the fact. >> dna is a good piece of evidence,er ebut we want to fi out if alexander bennett is really a part of this. >> reporter: a day after their plane was wheels down, detective childs was face-to-face with their target. >> alexander, right? >> uh-huh. >> i'm gary childs. how you doing? >> reporter: at first, the detective kept it vague, trying to confirm that bennett had indeed been in baltimore at the time of the murder. the year 2000. bennett said he was. he'd spent about a month on the streets there after being ditched by some friends on their way to a concert. >> i gotta tell you that's strange.

>> that's why -- it is strange. >> real strange. and then not to remember anybody you stayed with or hooked up with. >> reporter: then, the detective played his hand. laid out the reason for his visit. >> this girl's fingernails were taken at the time of her death. and under her fingernails is your dna. now there's no denying it. >> reporter: but bennett did have an explanation. and it had nothing to do with committing murder in a house. >> he remembers a confrontation that he had in a bus stop with a female in maryland, in baltimore, right around the time of the murder. >> i got kinda scared because, um, you know i was trying to fight back and i think i hurt her. i'm not sure. >> reporter: the detective didn't buy it. and thought he'd use bennett's story to his advantage. he presented bennett with several photographs, a technique police typically use to help identify criminals. except this time, he was asking a potential killer to identify his victim.

could bennett pick out the girl from his supposed fight? heidi's picture was included. >> he knows that he can't give this explanation about having this fight in the bus stop and pick some other girl. so our belief is that if we show him these pictures, that he will pick her. and he does. >> it also, too, kind of looks like her. >> reporter: there was one more crucial detail. remember the neighborhood block watch guy who frightened heidi? the one with the distinctive tattoo? >> do you have any tattoos on your left arm? >> yeah. >> can i see it? >> when i saw the tattoo on his arm and he picked heidi's picture out, i knew it was him. >> reporter: he was the block watch guy? >> he was the block watch guy. >> reporter: but they didn't have enough evidence to book him. so they decided to call in bennett's buddy from that crazy bomb plot, grant lewis, to see what he knew. and lewis was nervous. >> sorry if i'm shaking. i was kind of shaken up. >> reporter: he was evasive about his friend's time in baltimore, but the detective didn't buy his story.

outstanding warrant, the colorado authorities arrested him. the next day, detective childs kept pressing. >> i think you don't want to tell me certain things because you don't want to hurt a friend of yours. but what i'm trying to explain to you is nothing you say hurts him because what's done is done. >> reporter: at last, grant lewis cracked. he divulged a drunken conversation the two had down by a river after bennett got back. >> he said, i hurt someone bad. and i looked over at him and i said, i don't want to know. and he said, i think someone's dead. i think that's how he said it. i think someone's dead. and then he said, i knifed someone. >> reporter: that was it. corroboration. 12 years after heidi's murder, alexander bennett was charged. he was extradited to maryland to stand trial. heidi's brother frank got the news from their dad. >> it was another one of those things that just brings you to tears just because all that comes flooding back in. it's sa

feel like finally something's happened. >> reporter: stephen cooke's family was relieved as well. there'd been such a cloud of suspicion around him for so long that news that someone else had been arrested for his girlfriend's murder felt like vindication. >> i was just gosh, i was ecstatic. i was, wow, this is great. >> reporter: this is relief. >> yes. >> reporter: this is what we've been -- >> finally. >> reporter: -- saying for years. it's not stephen cooke. >> i was so excited for my brother. i was just so happy. he can finally put this behind him. >> reporter: two years later, in march 2014, both stephen and heidi's families converged on the baltimore county courthouse for the start of alexander bennett's trial. grant lewis was headed there, too. he'd been flown in to testify. he's going to be your star witness. >> absolutely. >> reporter: but for detectives, the idea that bennett killed heidi all on his own had never made sense. they held out hope that bennett would come clean, but he maintained his innocence. then came the morning of jury selection.

breakfast. and gary's phone goes off. and he looks down at it. he looks up at me. and he's like, alex wants to talk. and i'm, like, wow. here we go. >> reporter: a heart-to-heart with his mother had convinced bennett to spill everything. prosecutor garret glennon. >> she basically told alexander if he did this, it was time to come clean. that jesus would forgive him. >> reporter: what they call a come to jesus moment was what -- >> it appeared that way. >> reporter: you were beneficiaries of, huh? >> it appeared that way. >> reporter: bennett confessed that he killed heidi. but he hadn't acted alone, he said. he had an accomplice. and that person was who else, but the state's star witness. >> he and grant lewis, as in the bomb scheme, had developed an idea of being contract murderers. >> reporter: grant lewis is the brains of this operation? >> yeah, it was a lack of brains. >> reporter: grant lewis had been sitting in a hotel room preparing to testify. now detectives brought him in and turned the tables on him. >> grant, you're i

>> i am not in the middle of this thing. >> reporter: at first, lewis denied involvement, but as the detective revealed details from alexander's confession, he started to open up. >> did you send him to baltimore? >> i didn't send him to baltimore, but i know more about this than i've said. >> reporter: lewis ultimately admitted to being involved in a murder for hire scam but said bennett was never supposed to kill anyone. only to get the upfront money before turning the person who hired them over to the fbi. did you believe that story? >> not in the least. >> reporter: so now do you read grant lewis his rights? >> yes. and the cuffs went on. >> reporter: but there was still one major detail left. who hired them to kill heidi? coming up -- >> reporter: what really happened the day heidi died? a first-person account from the killers. >> i was making sure that she was alive. i didn't know. that's when i hath

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>> reporter: for more than a decade, detectives tried to untangle the mystery of 24-year-old heidi bernadzikowski's brutal murder. on the morning of his own murder trial, alexander bennett unexpectedly confessed to an opportunistic plot.

hit man. >> all right, alex, you all right? >> reporter: bennett agreed to a deal. tell the truth to investigators and avoid the possibility of getting sentenced to life in prison. interviewed by detective childs, bennett laid out the bone-chilling details of heidi's murder. >> grant was discussing about receiving money to kill somebody. >> reporter: according to bennett, he and lewis had been brainstorming ways to raise seed money for a nightclub. so lewis placed a coded message online, advertising discreet housecleaning services. >> by, discreet housecleaning, grant lewis apparently meant and hoped that someone out there on the internet would understand that to mean that they were hit men. >> reporter: bennett says a client did respond to the ad and offered $60,000 to kill heidi. >> i know from theli

the person, you know, emphasized to grant and grant emphasized to myself that it needs to look like an accident. >> reporter: bennett's role was the muscle to do the actual hit. lewis, the middle man, communicated with the client and organized everything. in late march 2000, bennett arrived in baltimore from denver. he says he waited for the signal to act. in the meantime, he scoped out his victim, breaking into heidi's home by tampering with the locks, then posing as that neighborhood watch volunteer who so scared heidi. >> i do remember her answering the door. >> reporter: did you go to the door to talk to her more than once? >> it was just that one time. >> just the one time? >> reporter: on april 20th, bennett says he heard through lewis that the plan was a go. after getting into heidi's house he hid behind the front door. >> now my plan was to just try to get her, and like, still make

maybe snap her neck or something to look like she fell down the stairs or something. >> reporter: heidi walked in through the door, and bennett says he pounced. >> when she came in, she saw me, panicked, i panicked and rushed at her at the front and, you know, tried to muffle her scream. i was making sure if she was alive. i didn't know. that's when i had the knife. and to make sure, had cut her throat. >> reporter: then, bennett said, he wiped the place down. and to throw forensics off he ransacked the bedroom and used heidi's lipstick to make that number one on the living room wall. after that, bennett says, he fled. that's it? >> that's it. >> reporter: heidi's dead. >> heidi's dead.

>> reporter: detective childs pressed, who was the client? he showed bennett a photo array of six suspects. assistant state attorney matt breault. >> he immediately separates four photographs and says, it's definitely not these four. and he's left with two. and he takes a couple of moments and stares at them. and eventually, he says, yes, this is him. i remember him. >> this one. i recognize him as the boyfriend. >> reporter: bennett picked out stephen cooke. heidi's boyfriend was arrested for first degree murder. >> deep in our hearts, we all had a feeling that he had something to do with it. >> reporter: stephen's trial began in june 2015. he pleaded not guilty. glennon and breault had the task of convincing a jury that stephen was capable of orchestrating a cold murder for hire. r

the word of one man, the killer himself, alexander bennett. you really had to believe this guy bennett? >> absolutely. >> reporter: your case was going to rise and fall on that? >> he was going to be the star witness against stephen cooke. >> reporter: bennett told jurors the same story he told investigators, how he killed heidi. video cameras weren't permitted, but bennett's testimony was audiotaped. he decided to confess, he says, because of his faith and for heidi's family. >> i wanted to be a human being. i wanted to give a family some type of peace. i wanted to have faith enough and to grow up into a man and to accept and take responsibility for what i did. >> reporter: but the question still remained. if stephen cooke had planned heidi's murder, why had he done it? according to stephen, they were in love and planning to marry. but some of heidi's friends testified that she was so miserable in the relationship, she was preparing to leave.

>> she had asked a friend of hers for a small loan for an easy storage facility in an effort to move out. >> reporter: and the real reason for the murder, the prosecutor told the jury, was pure and simple greed. $700,000. two months before heidi's death, stephen and heidi had taken out hefty life insurance policies on each other. i wonder why an hourly employee at a hardware chain is buying -- >> you should. >> reporter: -- almost a million dollars worth of coverage? >> as we explained to the jury, they had one car between them, which was hers. a red civic. they are not married. they didn't have any children. and they really didn't have many belongings. there really wasn't anything to insure. >> reporter: so once they buy the policy, it's tick tock. >> correct. >> reporter: heidi had no idea time was running out for her. no idea what was going to happen when her boyfriend dropped her home that night. but according to investigators, stephen knew there was a hired killer in the house. >> he set the wheels in motion. >> reporter: driving

>> he knew what was in that house. he knew what he was doing. doesn't get any worse than that. >> reporter: but the defense would have an answer for those insurance policies and everything else. and the person to explain it all to the jury would be stephen cooke himself. coming up -- >> the defense, just how strong was the prosecution's case? >> all you have are a confessed murderer's words. that's all. - "once upon a time a little girl learned how to read." her mighty parents kept the adventure going by reading her books that were beyond her skill level. her mind and her imagination grew happily ever after.

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>> reporter: alexander bennett, the admitted killer on the stand, had spilled out a gruesome account of the plot to murder heidi. stephen cooke, he testified, had hired him via the internet to kill his girlfriend. the motive? the boyfriend wanted her life insurance payout. 700,000 bucks. but stephen's defense attorneys conceded nothing. they thought the prosecution had a weak case overall and one big problem in particular. its star witness, alexander bennett. >> bennett obviously had something to gain by changing his y.

>> our old friend, quid pro quo. >> plea deal. >> reporter: tara lacompte and breon johnson were stephen's defense attorneys. they said before the colorado man's so-called confession, bennett faced life in prison without the chance for parole. but once he cut a deal with the state to testify, he could look forward one day to walking free. >> so he's singing for his supper here? >> i couldn't have said it better myself, exactly. the less time he would spend in jail for his own deeds. >> reporter: the defense argued another glaring hole in the prosecution's case was the lack of any physical evidence tying stephen to the crime. the computer in the house that stephen and heidi shared was never taken in as evidence. it's a digital crime at heart. >> not in this case. >> not in this case. >> what happened? >> heidi and steve did have a fairly new desktop computer, and that was never seized by the police. >> so to this day we have no idea what that hard drive on the home computer would've shown? >> no. >> so your guy is being charged with a contract killing, but nobody candu

>> reporter: not only did investigators not have any computer records. they didn't have a record of bennett's plane ticket, phone records, credit card receipts. eyewitnesses who saw bennett and cooke together. not even the murder weapon. stephen's sister kim. >> all you have is a confessed murderer's words. that's all. there's not one piece of evidence in this whole entire trial that points to stephen, other than the confessed murderer and these detectives with, oh, their belief. >> reporter: and when it came to motive, they turned the case on its head. the defense version -- this isn't about stephen searching for a contract killer online, but rather heidi look for love on a dating website and finding alexander bennett, who surprised her by showing up in baltimore. >> we thought that he met her online, came here to be with her and she rejected him and he killed her. it made sense to us. it made sense with the forensics. it made sense with the physical ev

>> reporter: to back up its theory, the defense pointed to this police photo of heidi's keys and bag. if, as bennett testified, he'd jumped her when she walked in the door, how did her door keys and makeup bag end up tidily on the kitchen table in another room? >> so the bag on the kitchen's table's not a trivial thing for you? >> no. i think she made it to the kitchen. i don't think he attacked her at the front door. >> make sure she was dead. >> reporter: and if prosecutors thought bennett was the foundation of their case, the defense felt it had its own star witness, stephen cooke. he would take the stand. >> the bottom line is by this time, we had come to the conclusion that it's bennett versus cooke. it's who you believe. >> for a second, i just looked at her like what in the world is going on. >> reporter: stephen told of finding heidi, the love of his life slumped on their living room floor that night. >> and then i just held her in my arms and was rocking her and crying, just calling her name and all. >> reportete

future together. and he was surprised when others said that they were finished. >> mr. cooke, you keep saying that you and heidi were going to get married. but we've heard from other individuals that she was thinking about leaving you. >> i've never heard anything like that until now. >> reporter: they were also planning for kids. and that was the reason he wanted a big insurance policy on himself. >> we were going to start a family. we were going to have children. and i wanted to make sure that there was enough money for heidi in case i died. >> reporter: he added it was heidi who wanted insurance for herself. he never pushed her to get it. >> heidi then asked me if it was all right if she could get $700,000 worth of life insurance. and i said, fine. >> reporter: the defense added there was proof heidi was actively nudging along the life insurance policy application. she'd faxed over some final documents just days before her death. it's a fact of the case, even heidi's own brothers harold and frank, can't quite account for. >> there's persuasive stories

and yet, there's also pretty compelling evidence that she was trying to get this insurance policy up and running. i mean, she's active in getting -- >> that's the -- >> -- the insurance going. >> yeah. >> yeah, i -- >> that's the biggest mystery to date. >> that's one of the things we don't fully understand. >> reporter: as for the murder, stephen flatly denied ever meeting alexander bennett and said he had nothing to do with heidi's death. >> now steve, you've heard through testimony that you arranged for heidi's murder via the internet. did you do that? >> not at all. not at all. i didn't -- i didn't have anything at all to do with heidi's murder. >> why are you testifying? >> i'm testifying because i want my family and friends and i want heidi's family and friends to -- to know the truth. and for 15 years, they haven't heard the truth. for 15 years, i've been blamed for something i didn't do. i didn't kill heidi. >> reporter: both sides rested. which argument would jurors believe? which man would they choose? the state and its key witness

or stephen cooke, the man with a good job, middle-class lifestyle and father of a 7-year-old son? the jury was out, but stephen cooke's sister knew the verdict she wanted to hear. >> he's not guilty. they're -- they're going to say, not guilty. they're going to say, not guilty. >> reporter: but after a day and a half of deliberations, that wasn't the jury verdict. >> guilty or not guilty? we find him guilty. >> reporter: stephen cooke was found guilty of first-degree murder, hiring a long-distance killer to murder his girlfriend. >> i felt like i lost my breath. i just was in shock. i just could not believe that's what they've said. i remember screaming, oh, no. >> thank you, lord. prayers are answered. it's relief, joy, and happiness and also sadness because we still don't have heidi. >> reporter: grant lewis, the denver middle man, has already

been sentenced to life in prison. both alexander bennett and stephen cooke was sentenced to life in prison without the option of parole. and remember the butcher terry gilliam? police have totally cleared him of any involvement. and in fact offered him an apology. >> it's not everything, but it does -- it's a start. it does mean something. >> reporter: as for heidi's family, their days are all about the kids and grandchildren. and parents who believe devoutly in a hereafter, always remember, of course, heidi. >> did you talk to heidi? >> oh, yes. i did. >> what did you tell her? >> i just said, sweetie, we finally got the answers we've been praying for. and justice will be served. >> that's all for this edition

"dateline." i'm lester holt. thanks for joining us. attorney d washington, d.c. plan to file a major lawsuit against president donald trump. this as president trump targets james comey using his own words against him. attorney general jeff sessions gets set to testify in the russian probe. chilling new video of a woman chained by her neck after being kidnapped bay serial killer. historic wins on the ice and clay. earliy today starts now. breaking overnight the attorney general of maryland and washington, d.c. plan to sue president trump. they call it a quote major lawsuit and said it