forever seared into the public conscious. evil personified. the man some say helped bring down the curtain on the 60s as an age of innocence. who ultimately, in his own twisted way, achieved the fame that he had been seeking all along. >> that's all for this edition of dateline, i'm andrea canning. thank you for watching. i'm andrea canning, this is [music playing] dateline. >> during the middle of the night, i heard this noise. it sounded like someone was in the house. i opened up her door, and, i'm

hearing things. >> your instincts were right. that something happened in the middle of the night. >> you think your child is safe in your home sleeping. >> she was just 16. emma the honor student cheerleader, volunteer. she can get along with anybody. always so kind hearted and sweet she wanted to be a nurse and she had a plan. >> she went to sleep one sunday night, and never woke up >> i saw a 16 year old female in her bed. there was a bullet hole in the wall. >> she was shot she had been shot from outside of the residents. >> was emma a target that weekend she had seen a mysterious figure dressed in black. >> she's unfair, she isn't panic. >> she was shaking. >> now, to brave friends set out on a mission.

could they help catch her killer? >> you're trying to bring down a murder suspect. >> everybody take their hands out of the vehicle now! it all became a lot more real. ♪ ♪ ♪ ♪ ♪ ♪ >> hello and welcome to dateline! emma walker was a spirited teenager with a knack for storing up fun. pretty and smart, she had a whole life ahead of her, but after her death, detectives faced a tough investigation. whoever had shot her had been brazen, and they had a bold plan to catch the killer. here's andrea canning with noises in the night! >> when the autumn chill seeps into the community just north of knoxville, tennessee, hundreds of high school students are drawn to the blaze of friday nights to cheer on their hometown heroes, the bobcats. she was the friday night light

who probably shone brightest of them all. emma walker, a cheerleader since her freshman here. >> she was a really good cheerleader, some would go through the motions but she would put her own sparkle on it. and what she would do. >> fellow cheerleaders kelsey and lauren said she could be sassy too. >> she said, i am kind of a big deal. >> and i'm taking it she said it with a hint of sarcasm >> yes. >> people who didn't know her, they're like, she is a super pretty cheerleader! but then they would meet her and see that she is the nicest person. >> -- they were longtime school friends. >> once you made her, it's like she was a down to earth person and really sweet. >> she had a smile that would light up the room. a big beautiful smile.

emma's parents say that infectious smile was the hallmark of her playful personality >> she like to play jokes on me. grabbing my iphone. taking selfies of herself. i had no idea. >> emma volunteered at an animal shelter. at school, she was an honorable student with a clear career goal. >> she wanted to be a nurse, and when we would talk about the different professions, and we get to the ones about babies. and she said that's what i want to do. >> it is no surprise that emma got noticed by boys at school. and there was one boy that she definitely noticed back. >> that's really all she talked about at first, it was just that he was super cute. >> he was riley. two years older than emma. popular too. the standout wide receiver on

the bobcats football team. >> did you think he was going to make it to the nfl? >> if there was anyone who was going to do it, it was him. >> heads grade school friend says it wasn't just a high school job. he was also in the church, and love star wars movies. >> -- . >> obviously. >> and then a little later in high school, he got a little bit more into football. but he kept with his nerd roots. >> it was really funny, and i think that's why i am a foul for him in the first place. because they were both super goofy. >> she had a big crush on him! >> she did! >> there was just one problem. riley already had a girlfriend. but he said he broke up with her to date emma. >> and things got serious pretty quickly between the two of them. >> yeah. >> but as the months went by, it was clear that riley, the school football player, was also a player. it turns out his acts was not

really an ex after all. >> he had promised his ex girlfriend that he would take heard a prom that year, and take emma the senior year. >> and she was okay with us >> she wasn't okay but she let it happen. >> she couldn't let go? >> no. >> that must be hard for a parent when you see a guy who has two girls on the go? >> yeah. >> that's not cool. >> no, but she had a mind of her own and did not want us to voice our opinions about it. >> emma's determination to be with riley caused a lot of tension between her and her parents. >> how does it work when you're trying to be that parents, and your daughter has that strong personality? >> it's difficult. >> very difficult! >> she was just very stubborn and thought her way was the right way. she wanted to learn for herself. >> riley and emma dated on and off for two years. when riley graduated and went off to college, just half an hour away, they tried to keep the relationship going. but just before thanksgiving in riley's freshman year, she said she saw snapchats of riley with

other girls on campus. she said she broke up with him for good. emma's parents say the tension at home evaporated. >> it must have felt so good to be a happy family again! >> it did. the whole household was different. >> the household was not calm for very long. on november 20th, 2016, a sunday, emma went for icecream with her dad. and plan to get up early for school the next morning. >> i told her i love you, i'm going to bed. and during the middle of the night, i heard this loud noise. >> what kind of noise was it? >> it sounded like someone was in the house, and opened a door and slammed it. and then i heard it again. >> mark jumped out of bed to check on emma and her brother. >> i opened up the door to her bedroom, and i stared at her for probably 15 to 20 seconds. and she was just lying asleep

in her bed. and, i shut the door. and went to my son's bedroom and he was in the bed asleep. so i thought, i'm hearing things! so then i checked the doors around the house, and went back to bed. >> in the morning, emma's mom jill woke up early. >> i went to wake up and i couldn't wake her up. >> what's going through your mind in that moment? >> i had no idea. and i can't recall a lot of it. i just know i check for a pulse. >> and there was no pulse? >> no pulse. so, you know. >> emma's younger brother also rushed in. >> for evan too, i bet that's something that you wish -- >> i wish he had never had to experience it. it's like a nightmare. >> jill called 9-1-1. >> i just tried to wake up my daughter for school, and she has no pulse! >> you say that she is not responsive?

>> yeah. >> what had happened to emma walker? >> coming up! >> the investigation begins! >> i saw a 16 year female laying in her bed with a small amount of blood on her pillow. >> people thought she overdosed on something. >> they thought she had ingested poison or whatever. >> this is a mystery right now? >> it's all a mystery. >> when dateline continues! hey jim! can we talk about casual fridays? oh sure. what's up? get fast, powerful cough relief with robitussin, and find your voice. ♪robitussin♪ i have moderate to severe crohn's disease. now, there's skyrizi. ♪ things are looking up, i've got symptom relief. ♪ ♪ control of my crohn's means everything to me. ♪ ♪ control is everything to me. ♪

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and find your voice. monday, november 21, 2016 was supposed to be was supposed to be a regular school morning. instead, first responders were arriving at the walker family home, and word that something terrible that had happened to emma was tearing her town apart. friends calling friends. >> she was just balling, and i was like you have to calm down and breathe and tell me what's going on. she said emma was, that i was like what are you talking about? because it didn't register in my mind. no, not our emma. >> it did not seem real at first to nathan either. >> i was like, yeah that's my best friend but she did not pass away. it hit me i started falling. >> emma's ex-boyfriend riley was at his home when his phone was flooded with calls and texts.

he wrote on social media. >> how much he misses her and loves her. >> she's at a better place now. tell god about our bible verse. >> did the hearts go out to riley? that he's lost. >> a lot of people had commented i'm so sorry. prayers for you. >> still, no one knew yet how emma had died. >> what are some of the rumors now floating around on social media about what happened to emma? >> people thought she might have overdosed on something. some kind of brain bleed. >> the biggest thing that upset us the most was people who didn't know her and were like, she killed herself. >> was there any part of you that was confused and thinking maybe it was possible? >> no. no part of me thought that emma would never take her own life. >> this is a mystery right now as to what happened. emma is there, and you know that she hasn't survived whatever has happened. but you don't know what! >> it's all a mystery. >> investigators arrived with just sketchy details from first

responders. >> they thought originally it was a suicide, that she had ingested something poison or whatever. >> major mike mcclain was put to investigate the case with major crimes detective allen marin. >> they found her lying in bed with a small amount of blood on her pillow. something would confuse that with her getting sick or a -- >> but when the detective looked closer, he's found something unusual. >> first responders did not immediately see the home in the wall. >> there was a hole in the wall next to her bed. a bullet hole. and only a little blood was visible on the pillow. when investigators inspected her head, they saw a small entry wound. >> so she's been shot? >> yes, ma'am. >> shot in her own bed! >> the bullet struck her just left and above the ear. basically a fatal wound. >> she had to have been shot through the wall? >> yes it's kind of obvious that someone had shot from outside of the residents into the residence, striking her in

the head. >> this is not the kind of neighborhood that has drive-by shootings. right? >> yes, ma'am, that's correct. it's a fairly low crime rate area. >> as the detectives process what was now a crime scene, they had more clues as to what might have happened. >> we got side the residents, and that's where we determined that there was a second shot that had been fired through the end wall of the house. >> so, bullet holes in two separate walls. and there, in the walker's yard? >> we found a shell casing. a spent casing that had been fired. and then, as we work around the residents, we found a spent casing and a live round. >> when emma's parents learned what had happened, they were barely able to take it in. >> they had told us that she had been shot.

>> it's unthinkable! >> emma's father mark recalled with horror those noises he heard during the night. >> knowing that those noises during the night were gunshots, and they sounded nothing like gunshots. >> but your instincts were right that something happened in the middle of the night? >> and you think your child is safe in your home. sleeping. >> but who would want to kill this sweet, popular girl? whose goal in life was to care for newborn babies? it turned out the last few days of her life had been anything but normal. and might be the key to unraveling the mystery. coming up! >> she sees a person dressed all in black. >> a mysterious figure at emma 's door. >> then this person comes to the front door, and starts trying to get into the house.

turning the doorknob, beating on the door. she is in fear and panic. >> i would have to say i will be absolutely terrified! >> yeah. >> when dateline continues! shingrix does not protect everyone and is not for those with severe allergic reactions to its ingredients or to a previous dose. an increased risk of guillain-barré syndrome was observed after getting shingrix. fainting can also happen. the most common side effects are pain, redness, and swelling at the injection site, muscle pain, tiredness, headache, shivering, fever, and upset stomach.

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of young people who feel they can thrive. ♪ ♪ emma walker was shot dead in emma walker was shot dead in her own bed. her own bed. at 16 years old, she had her whole life ahead of her. >> we know all the great things she would've done, proms,

graduations. things that we eoulf never get to see. >> getting married, having kids. >> as emma's family began to imagine life without her, police were focused on finding her killer. they were talking to her family and friends about the days right before the shooting. >> a lot of activity in a period of two days that is unexplained. >> it was the weekend before thanksgiving. friday night, emma and her group were celebrating at a friends house. her friend zach was at a party when emma received a text message from an unknown number. the message said something about riley, he had been taken. >> the text messages said someone has riley. >> someone has riley? >> yeah. someone kidnapped him. >> riley kidnapped? the strange messages kept coming then her phone rang. riley was on the line. >> he was screaming in the back, help me, help me, emma, i need your help. >> you can hear him

on the call calling for help? >> yes. >> and there was riley. >> he had his hands on his head, he was confused. i could see her yelling at him she was really angry. >> emma was confused with riley. she and her friends thought it was some kind of prank. >> it sounds very farfetched for him to be kidnapped. we didn't think twice about it. >> but if the kidnapping was a joke, what happened the next morning was no laughing matter. emma's friends told police that saturday she drove herself home from her friends house. >> as she's pulling into the subdivision, approaching her residence, she sees a person dressed all in black. and as she gets closer, he puts his hood up and sunglasses on. emma was texting her friends a play by play. >> she gets to the residence, then this person comes to the

front door and starts trying to get into the house. turning the doorknob, beating on the door. she is in fear, panic. so she reaches out to the one person that she thinks can help her. which was riley. >> emma had just broken up with riley, and was angry at him for what she thought was a strange kidnapping stunt the night before. still, she texted him this i hate you, but i need you right now. she faced called him and asked him to come over. >> why do you think she reached out to him given the fact that they had just broken up? >> i think he was security to her. and he was a protector from other things. >> riley searched the house and neighborhood but saw no signs of anyone. neither called the police. but now, detectives were investigating the murder. they discovered surveillance footage from the neighbor's house. and there he was. >> so this was the mysterious

man in black. >> at that point, it is. >> were you able to see a face? >> no. >> a possible intruder? a in tempted kidnapping? what was going on? police needed to talk to riley right away. they asked him for details about the kidnapping, and he insisted that it really happened. >> it was traumatizing, i didn't know what to make of it. i went up to my stepdad's house, and i pulled out of the driveway and this then pulled over across from the semi circle and these two guys were walking across the street. the next thing i know, one of them grabs my bag. the other ones around the corner and they just like, puts their hands over my face and just took me to their van or whatever. well why would someone do that to you? i genuinely have no idea. they did ask me, they were like, who would you want to talk to

for the last time -- so i called emma, and she thought it was a joke. she thought i was playing a prank on her. >> emma didn't buy the story. but she was genuinely terrified when she called him the next day about the man in black. >> and that's when she facetimed me. and she was crying and freaking out. so i said okay, i'll come check it out. >> that's the only person that reilly could think of who would want to harm emma. >> the only thing that i thought of was, whoever the person was at her. that saturday morning. that's the first thing i thought. >> riley told police, even though he and emma had broken up, he still cared for her. in fact, they spoke on the phone friday night in the hours before she was shot. >> i just told her how much i loved her, and that i was sorry that she had didn't wanted what we had anymore. she said she didn't care about the relationship anymore. she said she did care about me

and she loved me but she didn't want the relationship. >> riley was on campus about 25 miles away, crying over the breakup. >> i just sat there looking at pictures of us. >> he woke up to people texting and calling with their condolences. >> so i was like, what are you talking about? did you not hear what happened? i was like, what are you're talking about? >> riley had now lost the love of his life are good. but this pair of seasoned investigators had their radar up. >> you just start seeing more of his personality. you see that he had to have her. >> coming up a closer look at that mysterious man in black. >> she had actually seen the man in black. she recognized him by his build, his gait, the way he walked and carried himself. >> who was he? when dateline continues. when dateline continues. and often out of the picture.

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what's happening. a temporary cease-fire in gaza, underway, as israel awaits the release of the first group of hostages in a few hours. black friday, traditionally starting to mark holiday shopping season could bring to cheer for retailers. the national retail federation, forecasting holiday shoppers could spend a record 966 billion this season. that is a 4% jump from last year. now, back to dateline. now, back to dateline. now, back to dateline. >> welcome back to "dateline." welcome back to dateline. i'm natalie morales! who shot emma walker? the day before she died, a menacing man dressed in black showed up at her house, triggering a panicked call to her ex boyfriend, riley. then the man was gone. now detectives were about to discover something really did not tell them. and it would sense the investigation into overdrive once again, here is andrea canning with noises in the night. >> emma walker had been

murdered. and all over twitter, riley was the grieving ex. >> would he change the bio two? >> living every day through emma walker. rest easy my angel, i love you so much. >> and now, emma was looking back on her romance with riley. and they remembered a high school boyfriend who was jealous, possessive and even obsessed. >> he started to get very controlling of her. where she was, what she did, if she wanted to hang out with her friends. he was like, you're not going. >> he didn't want her to hang out with people. it was just him and her. >> and if emma went somewhere without him? he would text her 40 to 100 times. just blowing her phone up. and saying, emma, talk to me! text me back. call me. >> emma's parents thought the relationship was toxic. they had seen their daughter change. >> this new personality with riley in the picture was not

one that you recognized. >> no, not with emma. her fun loving self was no longer. she was very closed off, more in her room. more angry at us. >> was it kind of like her spark had been extinguished? yes. >> her parents said riley seemed intent on driving a wedge between emma and her family. >> he would tell her that she did not really have parents, barely a brother. and i think he just wanted her to think that she was all he had. >> this is a nightmare situation for a parent? >> yes. >> they had always been involved parents. monitoring the social media and cell phones. they even had a tracker on emma's car.

so when things got bad with riley, they tried to limit her contact with him. but he always seemed to find a way around the rules. >> he would show up to our church, because they could not tell him to leave. or a basketball game. because it was a public event going on. and they couldn't tell him he shouldn't be there. >> and when emma finally broke up with him a few weeks before she died, even his close friends said it seemed like he was unraveling. >> were you worried about him? >> very. >> i think this is when we started to see if he wanted to do something, he could. >> he seemed a little unstable to you? >> yeah. >> and now that emma was dead, her friends weren't buying his sad messages on social media. >> what do you think when you're reading his posts? >> he is trying to cover up for himself. >> did you think he did it? or something else? >> i thought he had something to do with it. >> police were thinking the same thing as they listened to stories about emma and riley.

>> based on my experiences as a detective, it was an abusive relationship. not physically, but most of a psychological or emotional type of abuse. >> police were skeptical of everything that reilly said. they did not believe that the kidnapping story. and when they talked to one of emma's friends in the neighborhood, they were even more suspicious. the friend was certain that riley was the mysterious man in black. >> she had actually seen the man in black, and believed it to really riley. she recognized him by his build, his gait, the way he walked,, the way he carries himself. >> the police were closely watching riley. they noted how he referred to emma in the strangest way. >> the girl, she texted me. >> which girl? >> the one that passed away. >> okay. what's her name? emma. >> this is someone that he has professed his love to, and gone on social media and spoke out about how she is his everything, and all that. but yet, when he goes to talk to me in the interview, he

refers to her as the girl! >> how did you get from there back? >> as the interview progressed. police tried to nail down his whereabouts the night she was shot. he tried to stick to the same story, he was at his college in tennessee. over half an hour away. crying in his car about the breakup. >> i remember getting back in my dorm at 4:30. it was really late. >> as police questioned riley. >> is there anybody else in your car? >> they became more and more skeptical, and he was in on it. >> am i a suspect in her death? >> did i say? well, based on my experience, it was an over the top lie. it was phony. >> i would hurt myself before i would hurt her. >> did you shoot into emma's house? >> no sir. >> despite his denial, riley was now the prime suspect. but they had to let him go. they did not have enough

evidence. and there was a missing piece to the puzzle. where was the gun that killed emma? it would take two young men on a dangerous mission to find it! >> riley is about to become the target of a secret operation. coming up! >> instead, we set up a listening device in the car. >> and the police could hear it but you couldn't hear them? >> yes. >> could these two friends find the missing gun and the killer? >> this potentially could be very dangerous. >> absolutely. you have two boys in the car with a guy that's believed to already have killed somebody with a murder weapon. this is a huge, dangerous thing. >> when dateline continues!

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subject 6: st. jude is hope. even today after losing a child, it's still about the hope of tomorrow, because. childhood cancer has to end. interviewer: please, call or go online right now. [music playing] [coughs] when caroline has a cough, she takes robitussin. so, she can have those one on ones again. hey jim! can we talk about casual fridays? oh sure. what's up? get fast, powerful cough relief with robitussin, and find your voice. ♪robitussin♪ >> the day before emma walker

and find your voice. the day before emma walker was killed, was killed, riley's grandfather called police about a handgun he owned. >> he filed the report that he has the gun stolen. >> the missing gun was a problem for riley too. he lived with his grandpa, and the gun was the same caliber as the one used to kill emma. police didn't think that was a coincidence. did he express that he knew where the gun was, or did he completely deny? >> he completely denied everything relevant to the gun. >> and after his denials to police, riley reached out to his close friends, alex and noah. since his breakup with emma, riley had been leaning on them for support. what did he say about how he felt about it? >> he was torn up.

throughout this whole time, i tried to spend as much time with him as i could and just be there for him, anything he needed. >> riley confided in alex and no again. he said he would never hurt emma, had nothing to do with the shooting. but he did have his grandpa's gun. >> they're gonna find a way to put this on me if they find the gun. it's like, can you help me get rid of this. >> the boys were willing to comfort riley, but not get rid of evidence in a murder investigation. instead, they called lieutenant merit. it's amazing that they called. >> absolutely. >> i mean, this is a big piece of the puzzle. >> absolutely. it could have -- they could've lived their lives, minded their business. >> riley told his friends he planned to go to the bluffs, high above the tennessee river, and toss the gun into the water. police hatched a plan, a bold and risky sting operation.

have alex and noah go with riley, and the moment they see the gun, signal detectives, who would swoop in and make an arrest. this potentially could be very dangerous? >> absolutely. you're gonna have two boys in a car with a guy that's believed to have already killed one person with a murder weapon, this is a huge dangerous thing. >> dangerous? for sure! and then, detectives made it even more complicated. they decided to secretly record the whole thing. >> they set up a listening device in the car itself, my car, it had a little thing inside my jacket which sucked because i couldn't take off my jacket the whole time. >> and he had the video as well. >> police could hear you, and you couldn't hear them? >> yes. >> everything came together with lightning speed. just hours after calling police, 18 year old alex and noah were wired up and ready to meet riley. what did your parents think about this? very vulnerable in this

position. >> my parents had just moved to north carolina, i was living in tennessee on my own. i didn't have time to talk to them. >> you did not tell your parents? >> i didn't. >> the plan hinged on the boys texting a secret word to detectives the moment they see the gun. without tipping off riley, the pressure was intense. >> this is insane. >> riley came over to noah's house, the mission was underway. >> i know that you really loved and cared about me a lot. >> we spent two years together. >> police were nearby listening in. as instructed, the boys tried to be natural. >> i'm sorry about emma, dog. >> i really -- i want to be so upset, but i can't, because i'm worried about being arrested and being put away for murder. never in my life would i kill someone that i loved that much. >> love you, bro. it's sucks you gotta deal with all this, man. >> riley clearly had no clue about the sting. he had faith in his friends.

>> i'm trusting you guys, like, with my life, because i mean, this is 70 years in jail if i get convicted for something i didn't do. >> why can't you just give them the gun? >> just -- it just needs to be gone. for whatever reason. >> you guys don't have to come with me if you don't want to. >> i mean, i got your back, man. >> if it's in the tennessee river, they will never find it. >> the boys headed out. first stop, riley's stepfather's house, where he had hidden the gun. he came out holding a plastic garbage bag. detectives were still tracking the boys closely, or trying to. >> it was a crazy part here, we have detectives watching them as they leave from the stepdads and at some point, we lose them. i mean, we lose sight of the

vehicle, we have lost the wire. >> is that a heart beating moment? >> yes. obviously we want to track them realtime, we want to keep up with them. >> police did find them again, in time to see the boys make an odd detour, on the way to the river, they stop for some drive-through fast food. >> yes, i need occasion chicken with two sides of hush puppies, with chili and cheese on it, and a large dr pepper. >> have you tried the cookout bro? >> no. >> oh my god, try it. >> you're in the middle of this critical undercover operation, and you've decided to go for some chili cheese fries? >> yes. >> why? >> it was almost the whole time, we were saying goodbye to one of our best friends. it was almost like comforting to have it be like it was before. >> they got to the bluffs around 11:00, and pulled into an apartment complex parking lot. alex knew the security code for the gate. he used to make deliveries there. and then, the big moment. the hidden camera didn't catch it, but alex and noah will

never forget it. riley pulled the gun out of the bag. >> oh, my god. >> noah texted the detectives, they were supposed to pounce. but 30 seconds passed, than a minute, no police. alex saw their suvs outside the gate. what was the delay? two minutes, still no police. the tension was unbearable. then, alex did something audacious. he took the gun out of riley's hands. >> this is a real gun. >> alex, why did you take the gun from riley? that was kind of a bold move. >> yes, it really was. >> i was watching from the backseat and saying, what? >> it was an instinctual thing, and riley grabbed it back out of my hands. that was scary. >> and that was when police got through the gate and made their move. >> what the? >> everybody put their hands out of the vehicle, now.

>> riley was cuffed and taken away, the gun was still in the car. >> just pull that back enough, and let's -- just to see the serial number. >> the mission was a success. alex and noah were safe. riley was charged with the murder of emma walker and taken to jail. it was the end of a long, crazy day. a popular football hero was behind bars. how did it all come to this? >> he was controlling and obsessive. but you would've never thought a murderer. >> and in a case already full of surprises, the biggest one was still to come. >> coming up -- a sudden change in riley's story, and it is a stunner. >> as crazy as it is, and as bizarre as it is, he was hoping that he could come to her rescue. >> what riley is saying is i'm not a cold blooded killer. >> would the jury believe it?

>> in the count one, charging the defendant with first degree murder, did the jury reach a verdict? >> when dateline continues. copd hasn't been pretty. it's tough to breathe and tough to keep wondering if this is as good as it gets. but trelegy has shown me that there's still beauty and breath to be had. because with three medicines in one inhaler, trelegy keeps my airways open and prevents future flare-ups. and with one dose a day, trelegy improves lung function so i can breathe more freely all day and night. trelegy won't replace a rescue inhaler for sudden breathing problems. tell your doctor if you have a heart condition or high blood pressure before taking it. do not take trelegy more than prescribed. trelegy may increase your risk of thrush, pneumonia, and osteoporosis. call your doctor if worsened breathing, chest pain, mouth or tongue swelling, problems urinating, vision changes, or eye pain occur. ♪ what a wonderful world ♪

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and find your voice. [dramatic music] almost a year and a half had passed since emma walker, was shot and killed through the wall of her bedroom. emma's ex riley killed -- pleaded not guilty. knocks attorney the prepared

for a high profile trial. >> why do you think this case has captured so much attention? >> people can relate to being a teenage couple in love. people can relate to break ups. and i think that one that really scared people in our community was that emma was asleep in her own home, in her own bed. >> was it stressful as the trial approached? >> yes. >> very. >> just the worries of what the turnout would be. >> prosecutors kevin allen and molly martin would have to prove to a jury, that it was riley who pulled the trigger. >> what was your strategy going into this trial? >> i think the main thing that we need to focus on at the beginning, was putting him there that night. and so, i think the cell phone records and the gps locations were very important up until that moment. >> they placed him around emma 's house?

>> he placed himself there. and the cell phone records placed him backwards. >> so he clearly told a lie about where he was when emma was shot? >> yes. >> the picture that we painted of riley, was a deceiver. someone who was phony. who couldn't get the truth out of him if you tried. but >> on the first day of trial, riley's defense attorney up ended the states case with an unexpected omission. riley was there. did fire the gun. but it was not murder. >> and that was a fairly stunning claim! >> from the gallery. veteran reporter jamie, saw draws drop. >> what he said was that reilly never intended to kill her. and in fact, assumed that he would not kill her if he shot through a wall. >> we'll ask you to find mr. call guilty of reckless homicide. >> not reckless murder? >> that's right a few years.

>> that would be a huge difference! >> all the states preparation went out the window. >> the case went from whodunnit to a state of mind offense. >> they said that riley was not a crazy killer, just crazy in love with emma. with a bizarre plan to win her back. >> when he fired that shot in the backyard, as crazy as it is, and it's bizarre as it is, they hope that he could come to her rescue. >> the defense told the jury that reilly only meant to scare them all with the gunshots. then if she needed comfort, he would swoop in and be her night and shining armor. the attorney argued that they had no idea the ballots was passed through the house. >> some of us do not know, or some of us may very well know, that you shoot through the wall. some of us may not. and i submit to you, riley, did not. >> that offense denied that riley was the man in black.

but admitted that the kidnapping story was a ruse. a stunt to get emma's attention. ryan's attorney says it showed how desperate he was to be with her. >> what riley is trying to do is get an opportunity to see emma. that's what he's trying to do. >> and that would later become a theme of his defense. that rather than killing emma, what he intended to do was play the rescuer. >> it almost does sound like he's just trying to scare her. when you first hear it. >> i would think the same thing, then i went out to the scene, looked at the house. looked at where he would be standing. and it is five feet away from the house. the measurements were. it's me, putting a gun right at you, and pulling the trigger. it was that close. >> so close, prosecutors say, it was obvious that riley was shooting to kill. >> shoot up into the air, shooting through the window.

anywhere. but where you shot. >> the state agreed with the defense on one point. riley was desperate to be with emma. but that desperation had become dangerous. prosecutors argued, of course he was the man in black. after that, and the kidnapping some failed, they said reilly gave up on winning her back. instead, they sneaked into emma's backyard. stood outside the window. and fired into the wall. knowing exactly where she slept on the other side. >> i think this is a case about revenge. i think that he sought to get back at her for the hurt that he perceived, that she was purposely putting on him. by breaking up with him. >> and after he killed her, the prosecutor say that he went to great lengths to cover his tracks. >> and he is going to throw the gun off -- the >> yes. >> they show the jury the video of that undercover sting. and how reilly tried to

manipulate his closest friends into covering up his crime. >> i'm trusting you guys, with my life. >> his plan was to get away with this. his plan was never to be caught. >> which theory with the jury believe? and whack-less act, or premeditated murder? they went off to deliberate and came back for hours later. >> in one count, charging the defendant with first degree murder did you reach a verdict? >> yes we did. >> what is the? verdict >> guilty. >> you heard guilty? what's that moment like? >> relieved. >> it's a sense of relief. >> riley was sentenced to a life in prison. he'll be in his 70s by the time he is eligible for parole. he has fired a appeal. >> we're proud of all the investigators and all the work, but we're almost more proud of noah and alex. >> are they heroes in this? >> i think they really are. >> lieutenant merit, the workers, they call you the heroes. what do you say about that? >> did what i had to do. >> it took a lot of guts to do what you did. >> appreciate that. >> as for emma, who used to

joke that she was kind of a big deal. she's actually become one. with tributes to her all over town. there is a scholarship in her name at central high. and the dog park dedicated to the young animal lover. >> it's just a good, fun, happy place to try their remember her. and other people to remember her. >> and here at the east tennessee children's hospital. and nicu exam room has been named in her memory. and they believe the best way to honor her daughter, is to remember what happens. detective marin says it's important to understand when teenage drama turns into

dangerous behavior. i >> think that we need to educate our young people about relationships, and what unhealthy relationship is. and what is psychological abuse. or most of yours. >> and we hope what someone gets out of the story is awareness. >> am i may be gone, but for those who loved her. the young girl, still sparkles. >> because she would want to be out there. and she would want us to be laughing and having fun. and not saying that you can cry all day you. still have to live life. >> that's all for this edition of dateline. i am natalie morales. thank you for watching! >> we were really close. and i couldn't give an answer. everyone asked me, where is your mom, couldn't give an answer. just so hard. that was surreal, kind of,