he threw a big party at his house. only two peoe didn't show up -- mom and dad. they couldn't come, they were locked in the bedroom -- dead. tonight on "20/20" -- when the party's over. >> his mom took his phone away and he said that he was going to kill her. >> and he did. then threw a blowout party with his parents still in the house. this is real. >> now his best friend takes you inside the crime. >> dad wakes up from his nap. >> he has a process that his son is holding a hammer, the woman he loves is laying on the floor. >> a tug of war over who's in char and his parents' plan to stop him before he stopped them first.

"can i reca "killer party." remember the headline -- a hazy night of passed-out party. >> everything after that was just black. >> no one has heard his part of the story, until tonight. the interrogation tapes, you'll hear them tonight on "20/20." teens trying the "good kid" high, but some don't survive. tonight, when the party's over. here now, elizabeth vargas. good evening. david is away on assignment. tonight, what so many teenagers are doing right now, across the country, having parties, some of them with alcohol, drugs and in our first story, something else, revenge against controlling parents, for teenager tyler hadley, the party to end all parties began with these ominous

words, when someone asked, when will your parents come home? he said, they won't, trust me. here's ryan smith. >> reporter: nestled on florida's treasure coast, 40 miles north of west palm beach, sits port st. lucie -- a city once designed for retirees, now teeming with working families. >> it's a maze of streets that all kind of wind together. >> reporter: there's the sense on these empty streets that something's amiss -- even the street signs aren't quite right. >> they didn't have time to spell the street names correctly. >> reporter: growing up here is a modest sort of happiness for any kid. but as novelist, nathaniel rich learned, that gets old. >> every teenager complained about how boring it was in port st. lucie. "the only thing to do is drink and get high. have parties." >> reporter: and it's a party that happened here that no one will ever forget. >> you're looking live at the port st. lucie home where police

say a 17-year-old boy killed his parents. >> a drug-addicted teenager who just wanted to party. >> he threw a big party at his house only two people didn't show up -- mom and dad. they couldn't come. they were locked in the bedroom -- dead. >> the million-dollar question is, why? >> reporter: a 17-year-old killing his parents -- an event that left a confused community looking to its teenagers for answers about high school senior tyler hadley. >> his parents were getting, you know, tired of him going out late, and getting drunk. >> they got more strict. >> his mom took his phone away. >> he was upset and he said he hated them. >> just something like teenagers say. >> definitely something that really upset him. >> everybody has, like, sick jokes. so we just thought it was like a sick joke. >> reporter: but what turns a teenager's sick joke into a sickening reality? tonight, we go inside the investigation into what made a boy scout turn into a teenager who did the unthinkable. mike mandell has known tyler since they were both 8 years old. he lived just a block away. so, you know, his parents.

>> absolutely. >> reporter: what were they like? >> they seemed like great parents to me. >> reporter: and how did tyler feel about his parents? blake and mary jo hadley thought sunny port st. lucie was the perfect place to raise their two boys, ryan and tyler. >> mary jo was a schoolteacher. and she loved kids so much. she dedicated her life to her two -- two boys. >> reporter: their father blake loved his job at a local power plant, but his passion was his sons. the baby, tyler, and ryan, six years older. what was blake like with the boys? >> he had a ball with 'em. he loved 'em. >> reporter: and in the beginning tyler seemed to be a happy little boy, celebrating birthdays and holidays with his family. >> he was constantly hugging his mom -- i mean, constantly. he would stand behind her and hug her and, you know, he was -- he was an affectionate kid. >> i remember him being a funny kid. he had a quick sense of humor. you never knew what was going to come out of his mouth. >> reporter: in a good way? >> sometimes. >> reporter: it was a quality that drew mike to tyler.

>> i was just walking around, trying to find a friend and stumbled upon tyler. he slowly became my best friend. >> reporter: over time tyler began opening up -- sharing with mike his secrets and his insecurities. >> he a lot of times bashed himself, and said he wasn't good enough. he just always thought someone was better than him. >> reporter: but what started as a kid's self-doubt turned into a teenager's anger. >> he started skipping school, hanging out with the wrong crowd, getting on drugs. you know, that's just things he was starting to do, was getting in trouble. >> he was starting to steal. and they said, "just hide your purse." i just thought it was one of those teenage things. >> reporter: tyler's parents started cracking down. how did they discipline him? >> they really did everything possible. as far as taking away the cell phone. bits and pieces of freedom that children really, you know, cherish at that age. >> reporter: but tyler pushed back, continuing to defy his parents. >> he didn't like following any rules.

he liked going out, doing drugs. then his parents caught on, he was already comfortable living that way, and he didn't want anyone to change it. >> reporter: nancy grace has followed the case. >> they were beginning to discipline him more and more and by that i don't mean take him out to the woodshed and give him a spanking. they would take away privileges. well, hadley would have none of that. his frustration and anger mounted. >> reporter: by the time tyler was 17, his parents were at their wits' end. they put him into an outpatient substance abuse program, but nothing changed. >> he came home drunk one night, and he crawled through his window, and his parents woke up. and they took away his phone and his car. he felt that she was over disciplining him. and, he said he wanted to kill her. >> reporter: did it sound like he might actually do it? >> absolutely not. >> reporter: and tyler's parents were keeping a closer eye on

him, taking him to a family reunion in georgia -- just one week before life would change forever. >> we really enjoyed having him. he was very polite, i mean he was -- i never saw tyler lose his temper, ever. that's what is so bizarre about everything. >> reporter: posing for family pictures one minute, but plotting with friends back home the next. >> he was texting his friends and telling them, "we're gonna have a party when i get home." so he was planning it while he was up there. >> reporter: and three days, this first ominous facebook post -- "party at my crib tonight -- maybe." >> tyler said he was gonna have a party tonight. >> a friend facebooked him "what about your parents? are they gonna come home in the middle of the party?" and hadley writes back "they won't, trust me." >> reporter: a party at tyler's house seemed odd with his parents now tightening the reins -- but it was something else he said that really got mike's attention. he tells you something about what he did the night before. >> yeah, he said he was contemplating murdering them that night, while they were sleeping in their bed. and he just didn't -- he said he

couldn't do it. he didn't have it in him. >> reporter: and what did you think when he told you that? >> i got a weird feeling in my stomach, but -- it's tyler. there's no way he would do this. >> reporter: then -- a few hours later. a second facebook post -- "party at my house, hit me up." this time there was no "maybe." tyler hadley's house party was set. >> he was bragging about it for days, he was going to have the party come hell or high water and nothing and nobody was going to get in his way. >> one of my friends had gone on facebook and seen the post about the party. >> there was so little to do in port st. lucie to do that night. any teenager who heard about the party was, was going to check it out. >> reporter: around 9:30 p.m., tyler picks up mike and some other friends and they head back to his house. jesse duryea is in the car. >> when we were pullin' up to >> and then he said, "something real crazy's gonna come out in the next week." said, "what do you mean?"

and he said, "you'll find out." >> asked him where his parents were, told me they were in georgia. >> there were no parents there. it was a free-for-all. kids could smoke inside the house. they were drinking. kids were bringing beer and, and pot and pills. >> reporter: what's it's like inside? >> young people drinking and sitting around talking. but, the weird thing was, most people in there, tyler didn't even know. i didn't know 'em. i don't know them. they were strangers. >> reporter: you think he wanted to be known as having this huge party? >> maybe. that's the only thing that makes sense. >> reporter: as the rowdy party rages on, a neighbor across the street makes a noise complaint. >> i woke up to, you know, squealing tires and kids hanging out of the car yelling. so, i did call 911. >> reporter: officers respond, but with no immediate cause for alarm, they leave the teens with a warning. when we come back, kids at the party are noticing there's something strange about this place. but only best friend mike mandell will discover how strange -- behind this door. >> my eyes popped up, this is real.

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continues. once again, ryan smith. >> reporter: in port st. lucie, florida, tyler hadley's house party is in full swing. 60 teenagers drinking and drugging with no parents in sight, tyler's older brother ryan away at college. >> one kid was walking around saying, "i smell dead people." other kids had seen some signs of blood, or what could have been blood. the house was a mess. it looked like it had been ransacked. >> reporter: as the night wears down, tyler is growing agitated. >> do you recall him yelling at somebody trying to go back towards the back part of the house? >> yes, i heard him just saying, "get out of the hallway. i don't want anyone in the hallway." >> reporter: how does he seem? >> he seems eager to tell me something, and he's -- wants to take me down the street and talk. >> reporter: so, you guys walk out the house. tell me what happens then. >> he says, "mike, i killed my parents." and i said, "no, you didn't, tyler. shut up." and, he said, "mike, look at the driveway, all the cars are

there. my parents are dead. i killed 'em." >> reporter: and then with partying teens still inside the house, tyler tells mike to look for the telltale signs -- blood by a computer desk where mary jo had been working. and by the master bedroom door -- but still mike doesn't believe it. >> i actually thought he went that far out to play a prank on me, that he actually put fake blood on the ground. >> reporter: really? you think he's playing a prank, at this point. >> anything but what it is, you know. >> reporter: the idea that teenagers are playing beer pong right here, while just steps away behind this door, his best friend's parents lay lifeless is too much for mike to fathom. >> i took tyler into the garage, and i said, "i want to see them dead, if you really did it. i don't believe you." >> reporter: tyler says he'll prove it after everyone leaves, but mike doesn't wait. >> i walk around back, and i go check for myself. i come up to the door. the party's going on over here, and i turn the doorknob.

pushed it, it opened. i looked down, and i seen his father's leg against the door. >> reporter: what was going through your mind when you saw his leg? >> my eyes popped up, and i said, "he's telling the truth, he did it. this is real." i'm in shock. i feel like there's no way i'm seeing this. wake up. >> reporter: then, mike mandell does something as shocking as the party -- he doesn't leave. >> now you'd think mandell would call his parents or take his cell phone and surreptitiously call 911, no. mandell continued to party hardy for several hours. >> reporter: why do you stay? >> it's -- it's a hard feeling to explain, you know. i knew this guy for so long. something wants you to stay here right now. "you know, you need to talk to tyler, and figure out as much stuff as you can." >> reporter: how long do you stay? >> couple hours. >> reporter: how do you do that? how do you -- isn't it eating you up inside? >> it is eating me up inside. even though you know he just

killed two people, you don't see him as a killer. >> reporter: you still see him as a friend, at that point? >> yes. >> reporter: why not try to get tyler out of the house immediately or call the cops? because he could be a danger to everybody in that house, including you. >> i was still in shock. >> reporter: then, a bizarre moment between best friends. they take this selfie. i have to show you something here. why did you take this picture? >> because i knew it was going to be the last time i ever seen him. >> reporter: so this was to remember him. >> yeah. >> reporter: lot of people look at this picture and they say -- "mike's callous. he doesn't care." what do you say to those people? >> look at the picture. am i smiling? is tyler smiling? when i look at that picture, he looks very worried to me. >> reporter: and how do you look in this picture? >> i look like that this is the worst day in my life. i knew i was going to call the cops on him when i took that picture. >> reporter: in shock and unable to keep it to himself, mike tells another friend. >> he showed me the blood splatter on the baseboard. >> okay, on the baseboard? >> near his parents' bedroom. >> what did you do?

>> i basically told him that i was getting the hell out of there. i was like, "i'm leaving. you can come with me." >> reporter: mike is still reluctant to leave his best friend, but when he finally does, tyler is quick to notice. >> tyler calls me on my cell phone. and he said, "mike, where'd you go?" you know? "party's still happening." and i said, "tyler, i'm tired. it's 4:00 in the morning. i'm going to sleep." and he said, "okay, man. well, i'm having a party tomorrow. are you going to come?" and i said, "yeah. i'll be there." >> reporter: this is a party tyler never wants to end -- and at 4:40 a.m., he posts on facebook -- "party at my house again, hit me up" but mike mandel; won't be there. >> immediately after i hang up the call, i call crime stoppers. >> we got a call from our call center. he's claiming he killed his parents -- >> reporter: what were you thinking as you're making that call? >> it wasn't a good feeling.

you know, i still knew that i had to do the right thing. >> reporter: and the friend mike told also calls police. >> the kids i spoke to who were at the party were shocked that they had been at a murder scene. but they also thought it was pretty cool that they'd been at this famous party. >> there had been a homicide. a 17-year-old young man had killed his parents with a hammer. >> reporter: what was your first thought? >> first thought is, "no, 17-year-olds don't kill their parents with a hammer." >> reporter: when detective kristin meyer arrived on the scene in the wee hours of the morning, remnants of the party are still apparent. >> we find beer bottles everywhere. they're all over the front yard. >> reporter: knock on the door. >> lights go out. one officer gets cover and starts calling for backup. this officer hear the door opens. and there stands tyler. >> reporter: when we come back -- it's the question

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"20/20" continues. once more, ryan smith. >> reporter: at dawn, when police arrive at tyler hadley's house, the party is over. officers see tyler alone inside, pacing back and forth. >> and they creep up to this window because they can peek in. >> reporter: what kind of state was he in at that point? >> they talked about the look on his face, one officer describes it as deranged. >> reporter: officers ask where his parents are -- >> he said, "they're out of to. they're in west palm beach." he's placed in handcuffs, and the officers go in and search. >> reporter: and inside the

master bedroom they find what looks more like a garbage pit than a place where tyler's parents slept just 24 hours before. the room is packed with items from all over the house -- furniture, magazines, pictures, food, mom's "good housekeeping" magazine, homework from her students, a family calendar. underneath, investigators find the bodies of blake and mary jo hadley. it's the darkest turn possible for a saturday that began with ordinary errands for the hadleys. a trip to the local farmers market, a visit to a dress shop. they were back home early afternoon, his father taking a nap, his mother at the computer. tyler told his best friend michael mandell that to psych himself up he listened to the lil boosie song "feel lucky." then he grabbed a hammer. >> he said that he stood behind his mother for five minutes, while she was on the computer, trying to figure out whether or not he should hit her or not. and at some point, he hit her. >> reporter: mary jo's screams

woke his father. he rushed to the doorway and was stunned by what he saw. >> and he couldn't even move. and, tyler said he ran up to his father, hit him, and his father asked him why he's doing this, and he said, "why the [bleep] not." >> reporter: tyler told him that he then dragged his parents' bodies to their bedroom, then spent hours cleaning up the blood. stripping the walls, leaving empty hooks where family photos once hung, adding them to the pile. at some point, during all of this, tyler makes that post on facebook that the party is on. he uses his parents atm card to withdraw $400 in cash and buys beer for the party. >> at the party he's having a great time. he's playing round after round after round of beer pong. he's laughing, he's joking, he's planning a party for the next night. >> reporter: tom bakkedahl, the prosecutor assigned to the case, tries to make sense of the grisly murders. >> this is not your kid from the wrong side of the tracks. this is not your kid who was

raised in an abusive, violent family. and these parents gave him everything. >> reporter: investigators find evidence that points to premeditation. for months, tyler repeatedly talked about killing his parents to his friends. >> his mom took his phone away. and he said he was going to kill her. >> he said something about, "oh, i'm just -- i'm going to kill my parents." >> i just specifically remember him saying i am going to kill my parents. >> he just said it with a smile, so that's why no one took it too serious. >> reporter: but no one knew just how calculating their friend was. he hid his parents' cell phones before killing them, and with no land line, he knew they couldn't call for help. less than a month before he was to face trial, tyler pleaded no contest, leaving a controversial question, his punishment. he could be protected by a recent supreme court decision, which ruled that for juveniles life in prison without parole is unconstitutional. but prosecutors argue that with a crime so heinous, tyler should never see the light of day.

>> he sentenced the whole family to life. >> reporter: but tyler's defense team argues that tyler was mentally ill. >> he had major depressive disorder. >> he was suicidal. >> reporter: he was drinking heavily and abusing drugs, but the counter to this would be -- a lot of people have disorders, take drugs. some even take illegal drugs, yet they don't kill their parents. >> what i think is one of the most important -- factors, is the juvenile brain. the juvenile brain doesn't fully develop until the age of 25. >> reporter: but the prosecutor says tyler, just 153 days shy of his 18th birthday, should be treated as an adult.

as for the motive, could it really just be the party? the prosecutor pored through messages tyler exchanged with his friends for clues. in that, tyler complains about the outpatient rehab program he's in writing: "i seriously hate that [bleep] for real." >> he wanted to have a party. there's no question about that. the decision over tyler's fate has ripped the family in two. his mother's side mary jo's mother -- tyler's grandmother, hoping for parole. >> i just want tyler not to spend the rest of his life in jail, because i know, i know, i know he's a life worth saving. >> reporter: but for his father's family, like mike and cindy hadley, forgiving their nephew is out of the question. >> this is a cold-blooded murderer that we're talking about here.

yeah, he's my -- he's my nephew and i love him. all right? but there's only one sentence. is life in prison. >> reporter: you don't think there's any way he could rehabilitate himself and be a productive member of society? >> would you want him living with you? if he got out? >> reporter: mike's concern, now entirely for tyler's brother ryan. >> that's the person that we need to feel sorry for, he lost his entire family. you know, he lost three people -- his mom and dad and his brother. >> state your name, please. >> ryan hadley. >> do you love your brother still? >> i do love my brother. >> are you hurt for your brother still? >> yeah, i hurt for my brother. >> reporter: but that love for his baby brother has its bounds. >> under what circumstances would you like to maintain this relationship with your brother? >> well, what i want is for him to get the maximum penalty possible. >> reporter: finally, tyler speaks publicly about the crime,

but offers little insight as to -- >> i'd like to direct this to my entire family, everyone, all of them. i know it's hard to understand and you can't begin to explain what happened i just want everyone to know that i am -- i am truly sorry for, you know, the acts i committed. >> reporter: the judge was unmoved. two weeks ago, he made his decision. >> it is hereby the judgment and sentence of the court, the defendant be sentenced to life without the possibility of parole. >> no one wants to see a youth behind bars, but he murdered his parents, a colder heart i've never seen. >> reporter: if he were here today, if you could speak to him directly right now, what would you say to him? >> well, of course, i'd ask the

question, why? i might ask him, "do you miss your mom and dad? didn't they mean anything to you? was it worth it? are you happy now? hope that party was worth it." you just seen tyler hadley's grandmother on the stands saying he has a life worth saving, do you agree? should he have a chance at parole? tell us on twitter. we'll be right back. next -- a 14-year-old. a high school senior. and what really happened during that drunken party. >> they kind of egged me on to drink from really shot glass. >> now his take. the interrogation tapes just released to "20/20." when we return. ...exclamation point... happy smiley face? yes, i did! did you know that more people

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tillamook pepper jack, tastes better because it's made better. it's the high school he said/she said that rocked a small town about a night of partying, drinking and sex that made national headlines. we have heard her version of what went on. but tonight, for the very first time, his version. that senior high school football player on interrogation tapes, just obtained by "20/20." will hearing his words change what you think about the story? or outrage you even more?

here's matt gutman. >> you have the right to remain silent. >> reporter: this is 17-year-old matt barnett sitting in a police interrogation room. >> did you understand these rights as i've explained them to you? >> yes, sir. >> reporter: and this is daisy coleman, whose life changed forever because of what happened between them. two teens facing tough repercussions for a night of mistakes. >> you had a lot of young people that made a lot of bad decisions, and they ended up getting caught. >> reporter: 14-year-old daisy coleman. >> sexual assault charges. >> a high-school sexual assault case is making headlines once again. >> reporter: the pair were at the center of an alcohol-fueled teenage sex scandal that gripped the nation and divided a community. >> bad judgment calls. for everyone. >> reporter: daisy is the face you almost never see, the teenage victim shedding anonymity to speak out. >> i really wish more girls would tell their story. >> reporter: it all began in maryville, missouri, an all-american town full of cows and cornfields, where football

is king and it's players royalty. and perhaps none more popular than matt barnett, a tall broad-shouldered defensive end for the maryville spoofhounds. cheering him on, a beaming and bubbly 14-year-old daisy. the two began exchanging texts. she's a freshman, matt a senior in the cool crowd of athletes, along with daisy's oldest brother charlie. here they are together at prom. but charlie was concerned with all that flirty texting. >> i told him, i was like, "quit texting my sister." >> reporter: he didn't stop texting your sister? >> no. and i told her stop. and i was like, "listen, he's a senior. you're a freshman. you're my little sister. you can't be talkin' to him." well she didn't listen. >> reporter: no daisy didn't. something she would later regret. one frigid january evening daisy was having a sleepover with her friend, a 13-year-old girl named paige.

>> she just came over, we started watching scary movies. >> reporter: they say they also started drinking, sneaking alcohol from daisy's mother's closet. >> i was in high school and everyone was already doing it. so i was like, "oh, i might as well try this." >> reporter: that night daisy was also texting matt. here for the first time are some of those messages the pair arranging to meet. >> lol. u wanna come drink wit me and chill. >> omg. >> he asked to hang out. so we snuck out of my house around one, and he drove us to his house, and he had to sneak us through his basement window. >> reporter: and into matt's bedroom seen here. also at the house were four other popular boys. among them, some of charlie's best friends. >> those were the guys i was with every single day. >> reporter: you could've trusted them like a brother and you'd hope that you could've trusted them with your sister. >> yeah, i hoped. >> they kind of egged me on to drink from this really tall shot glass.

>> reporter: these are photos of the aftermath of the party obtained by abc news. trash, empty plastic cups, and a bottle of bacardi. the boys at the party at night estimate that daisy drank 5 to 10 shots in a 15-minute span. >> everything after that was just black. and that's all i remember. >> reporter: she might not remember, but matt does. this video, matt's police interrogation, is the first time ever we get to hear from matt barnett himself. >> did she ever say she didn't want to have sex with you? >> no. >> reporter: his words providing new key clues in what could have happened that night between him and daisy. >> so you and daisy had sex in your room? >> yes. this is before she started drinking at my house. >> reporter: central to case, the timing of when exactly daisy downed all those drinks. >> was she drunk out of her mind? >> when i was with her, when we were having sex, no. >> reporter: matt barnett tells police their sex was consensual and that daisy only drank to excess afterwards. >> when you picked her up at her house, was she drunk?

>> i wouldn't say drunk, i'd say she was -- >> buzzed? >> yeah, buzzed. >> then you took her home, you and her talked, you had sex. then she came out after having sex, wanted to have another shot. >> yeah. >> reporter: critical point in the investigation that followed because in missouri, a 14-year-old girl can't consent to sex if she's incaps tated. and tonight, never before heard accounts from the other boys present that night. like jordan zech. >> and then they went back into the bedroom and had sex again? >> no, matt said he didn't have sex with her the 2nd time because he couldn't get a [ bleep ]. >> reporter: paige, who was waiting in another room, describes her friend daisy as completely wasted and couldn't even walk. >> and they just started panicking a lot, saying "how are we going to get her dropped off, without her brothers waking up, without them hearing us." so they brought us back to the house and dropped her off. and then just put her in the yard, and they told me to go back inside and that she'd be

fine, she just had to sober up. >> reporter: all the while, melinda coleman thought her daughter was safely asleep in bed all night long. it was 5:00 a.m. when daisy was discovered. >> the dogs started barking which woke mom up and my youngest brother. >> and she had just sweat pants and a t-shirt on. her hair was wet and frozen. >> and then i was woken up to, "charlie, wake up. wake up, charlie. there's something wrong." >> reporter: daisy had been abandoned on the lawn for almost three hours wearing no shoes or socks. >> it was terrifying. i couldn't understand why she was outside. >> reporter: melinda says she thought maybe daisy had been sleep walking. but when she put daisy in the bathtub to warm her up, she noticed marks on her body. >> i asked her if she was hurting and she kind of said yes, and started crying. >> so my brother and i went in the yard and found a phone, started reading these messages from matty. >> reporter: did you instantly know what happened?

>> i instantly knew there was something going on. the last message on there was, "i'll be there in a minute." and i was -- i was so mad. >> and then i took her in to the emergency room. the doctor said that she had been raped. and it was definitely my worst fears. i, as a mom i just -- it just hurt so much and you want to take the pain away. and i think i knew what she was going to go through. >> reporter: barnett was arrested for sexual assault. and to melinda's dismay the charges were quickly dropped. and daisy's life began to completely unravel. she was suspended from cheerleading after admitting to drinking and was bullied at school. >> people would generally just yell stuff. like, they would yell "liar" or the "s" word, or they would call me the "w" word. >> reporter: things got so bad, the colemans say they were forced to move. but that didn't stop the digital onslaught. >> the stuff on facebook and twitter was just unbelievable,

so horrible. saying stuff like, "why don't you slit your wrists." >> i began self-harming, and i was very suicidal, and i really started to hate myself. >>eporter: daisy was down, but her mom melinda wouldn't let her be silenced. they embarked on a national media campaign. >> and i think they need to let him pay at least some price and some punishment, so he can learn. >> justice for daisy! >> reporter: and melinda ignited a firestorm back home, trying to get justice for daisy and for other girls afraid to speak out. >> supporters held daisies and lit candles to represent the alleged victim. >> reporter: a special prosecutor was brought in to take a fresh look at the case and those previously sealed interrogation tapes. >> how long do you think you and her were in the bedroom together? >> like 15 minutes to 20 minutes. >> reporter: after a ten-week investigation, this past january, the final word. >> today mr. barnett pleads

guilty to endangering a child in the second degree. >> reporter: that was for leaving daisy on her lawn. t as for rain charges -- >> there was insufficient evidence to go forward on a sexual assault. >> reporter: vindication for matt barnett, cleared by two independent investigations. proof he says that he did not sexual assault daisy. >> did the girl you had sex with ever say she didn't want to? >> no. >> ever say she did? >> yeah, she did. >> reporter: as for daisy, she tells us she's happy. now, a junior at a new high school and looking to put the whole ordeal behind her. >> when something bad happens in life, no one stops. life keeps going. and i think that's something i just had to learn. >> new tapes you just heard about were all about the timing of the drinking. are you persuaded by the tapes? do you think that that football player is telling the truth? let us know on twitter.

we'll be right back. coming up next -- getting high without drugs. the so-called "good kid" high. >> it seems insane to me that kids would choke themselves for fun. >> next, on "when the party's over." 0 dollars a month. sounds great. sounds like a slam dunk. oh you a basketball fan? yeah, i played a little. hmmm, me too. lily adams. point guard. high school jv. grant hill. small forward. college and professional. oh, good for you. introducing our best-ever family pricing. for instance, a family of four gets 10 gigs of data, with unlimited talk & text, for $160 dollars a month. only from at&t could save you fifteen percent or more on car insurance.s everybody knows that. well, did you know bad news doesn't always travel fast? (clears throat) hi mister tompkins. todd? you're fired.

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valentine's day seven weeks ago, when a mother should be so excited about her son coming home from middle school, bragging about how many cards he got or who his secret admirers might be. instead she got a 911 call that would plunge into an underground she could not imagine, teenagers looking for what's been called "the good kid" high. this week, i sat down with a moth moth mother. >> three minutes.

what can you do in three minutes? >> listen to your favorite song. >> because that's what happens if you play the choking game. >> reporter: the choking game is all over the internet -- but it's not a game. but even after years of battling the problem and online awareness campaigns - - we're still seeing this. what looks like do it yourself videos on youtube. >> so today, i'm going to choke myself. >> reporter: this boy climbs a makeshift gallows, seconds later, he is coughing and holding his throat. >> how did i miss this? seriously, because apparently it's been around for a really, really long time. it seems insane to me that kids would choke themselves for fun. >> there you do, got it. >> reporter: with a new baby, this should be a happy time for kristina fields. she's an army mom. her husband, dana, is a soldier. stationed at ft. carson, colorado, they're raising five children.

but, next to the majesty of pike's peak in the rockies, a senseless tragedy. six weeks ago, her oldest child, 13-year-old louie, is found on the floor of his middle school bathroom unconscious. his mother gets the call. >> i was like, "is my son okay?" and there was a brief pause, but it was the longest pause. and she was like, "911's been called. we need you here right away." >> reporter: they rush luie to the hospital but there is nothing they can do. >> and i just kept praying that i would just wake up because this is not real. like, i just saw him this morning. i -- i gave him a hug and a kiss, and i sent him to school. you're supposed to come home from school. and i was like, what the hell happened? like, what could happen at school? and they were like, "he hung himself with a belt." it was like -- like, it was just a normal friday thing to do. like, okay. >> reporter: the army says its investigation is still active. but the death certificate says it was suicide.

and kristina believed it, at first. but it was strange. louie didn't seem depressed to her. he was grounded, but here he is in a home video, the night before he died, joking around as usual. >> we cannot move from this spot. >> reporter: he didn't leave a note. and another odd detail from the day he died -- >> from what i was told from the investigators, he asked a friend to go with him to the bathroom. >> reporter: to commit suicide? >> that's my exact question. >> reporter: and then, the day of the funeral, kristina finds a stunning voicemail on her phone. its from louie. >> and when i scrolled down, i saw his name. and i was like, "what?" >> reporter: a month before he died, louie had unknowingly pocket-dialed his mother. it's hard to hear, but kristina says one terrifying telltale

word jumps out - - "choke." >> choke me again. >> reporter: did you have any doubt in your mind after listening to that accidental voice message that that's what louis was doing that day, that he and his friend were playing the choking game? >> not after listening to that. i believe that that makes sense. >> reporter: why would anybody want to choke themselves? what on earth is fun about it? >> it's the thrill of testing limits, of going to the edge. >> it's described as a euphoria. >> reporter: it is sometimes called the "good kid" high. >> it's typically what you see the happy kids do because they don't want to resort to drugs and alcohol. all these kids you hear, when you talk to their parents and their friends, they're happy kids, they're good kids. >> reporter: one foundation estimates the total number of deaths at between 250 and 1000 a year, but no one really knows for sure. it seems like a no-brainer. choking yourself is dangerous. why don't they understand that.

>> right. because they don't think that the really bad thing that might happen from choking -- >> reporter: death? >> death will happen to them. teenagers think they're invincible. >> reporter: back at fort carson, tonight -- >> so this is louie's room. his bed is exactly the way it was when he left for school. >> reporter: an unmade bed, an unfinished sketch book -- reminders of a boy who is never coming home. his family hoping their grief will serve as a warning. >> there are so many kids that are dying from this because they want to get that high, and they don't realize it by themselves how dangerous it is. if you think your kids are playing the choking game and want help, go to our website at abcnews.com for more resources. we want to know what you think about kristina's story, tweet us

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from the makers of frontline® plus. that's our program for tonight. but tune in tomorrow for "20/20" saturday at 9:00 p.m. eastern tonight it was kids behaving badly. tomorrow night, you might argue

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