This Terrifying Case Will Leave You Speechless | True Crime Documentary

“Am I a suspect in her passing? Should you be? I need to get rid of the gun. Off the bluff? I’m going to throw it into the water. They will never… They’ll never find it.”

He got more possessive and more clingy towards her.

On a Friday morning in 2016, Emma Jane Walker woke up to a soft kind of October golden autumn light. She was 16. She had cheerleading practice that day, small plans, and a future still ahead of her. And in truth, she deserved the chance to have lived it.

Across town at a small college called Maryville, William Riley Gaul was already awake, too. He was 18. Things didn’t just look the same for him anymore. He had recently been dropped from the football team, no practice to go to, no routine to follow, just time, his thoughts, and his phone, and one person he couldn’t seem to let go of, Emma.

They had known each other for 2 years and dated for 2, but Emma had ended the relationship, and maybe that should have been the end of it. People break up, they move on. That’s how it’s supposed to go, right? But this didn’t end there. As the weeks passed, something changed, quietly at first, then more clearly. The distance between them didn’t bring peace, it seemed to create something else entirely, something much more complicated.

By November 21st of that same year, everything would change. Only one of them would still be alive, and someone would be desperately trying to erase every trace of what happened. You can’t help but ask, how did a teenage relationship turn into something this fatal? Well, let’s find out.

Emma Jane Walker was born to Jill and Mark Walker. From the very beginning, her mother said, her name had always meant to her chosen, wanted. Jill always wanted a baby girl and wanted to name her Emma. “When I finally had one, it was a huge blessing,” she said.

Emma grew up in the Sterchi Hills neighborhood of Knoxville. It was a quiet one. By the time she reached high school, Emma stood out, but not in an overwhelming way. She was naturally beautiful, warm, and easy to be around. And then, there was something else her mother mentioned often. She was strong-willed. She had opinions. She had standards. She didn’t just go along with things.

And even at 14, she already seemed to know what she wanted. Emma wasn’t just thinking about the future in a vague way. She had a clear plan. She wanted to become a neonatal intensive care nurse. She wanted to take care of premature babies, the smallest and most fragile patients. And this wasn’t something someone pushed her toward. She had chosen it herself. The East Tennessee Children’s Hospital wasn’t far from where she lived. She talked about it in a way that felt real, like she could already see herself there one day. It’s almost rare to see someone that young be so sure.

In the fall of 2014, Emma started at Central High School as a freshman and almost immediately did something most freshmen don’t. She made the cheerleading squad. In fact, she was the only one in her year to do it. Lauren Hutton was a senior then, and she spotted Emma immediately.

“Emma really took cheerleading seriously,” she said. “Emma didn’t just hang around or watch from the edge. She showed up ready to give it her all, and honestly, she nailed it. People noticed her, but not because she was loud or pushed to be in the spotlight. It was something quieter, more subtle. Being around her just felt easy.”

Her friends described her as loyal, generous, and funny. Someone who truly cared about the people close to her. She also had a deep love for animals, something her family would later remember very clearly. She had dogs, and if it were up to her, she would have had even more. She was, in many ways, just a normal teenager, but in the best sense of that word. Full of life, clear about what she wanted, just getting started.

That was Emma’s world in September 2014, and it was during that same month that she met Riley Gaul. At the time, Riley Gaul was a junior at Central High. He wore number eight on the football team, a wide receiver, two years older than the girl he had started noticing on the cheerleading sideline. People who knew him back then didn’t describe him as the typical jock. One friend even said he was a little nerdy on the side. He played video games. He could be funny. For the most part, he seemed ordinary.

When Emma’s parents, Jill and Mark Walker, first met him, they liked him. Jill would later describe him as the boy next door. She said he was polite, kind, and easy to be around in the beginning. Mark felt the same. To him, Riley seemed well-mannered, respectful, the kind of young man you don’t immediately question. So, when the two of them started dating, it didn’t raise any concerns. Emma was 14, Riley was 16, a cheerleader and a football player at the same small high school. It almost felt expected, like the kind of relationship people see all the time, especially in a place like that. And early on, nothing seemed off. No obvious red flags, no clear reason to worry. But sometimes things don’t show themselves right away. And in this case, that would slowly start to change.

There are two things that often define a controlling relationship, isolation and control over decisions. It moves faster than it should, and over time it slowly takes things away, friendships, independence, even a person’s sense of what feels right or wrong. It doesn’t happen all at once. It builds little by little. As Riley Gaul’s relationship with Emma Walker went on, the people closest to her started to notice the change. He became more possessive. According to friends and family who later spoke about it, he paid close attention to who Emma talked to. He had opinions about what she wore, where she went, and who she spent time with. He didn’t like certain friendships, and he made that known. Some of the things he said to her, a 16-year-old girl should never have to hear that from someone who claims to care about her. It’s honestly hard to absorb.

Emma’s parents saw it, too. They tried to step in. They set boundaries. At one point, they told Emma she wasn’t allowed to see him anymore, that he wasn’t welcome in their home, but Emma was strong-willed in ways that didn’t always make things easier. She kept seeing him.

After Riley graduated from Central High, he moved on to Maryville College, about 16 miles south of Knoxville. He had earned a spot on the football team as a wide receiver. Technically, the relationship became long distance, but distance didn’t seem to create space. If anything, his focus on Emma grew stronger, and by the autumn of 2016, Emma was starting to realize something important. She needed to end it. She had tried before, more than once. The breakups didn’t last, not because she didn’t mean them, but because his reactions made it difficult to walk away. It’s the kind of situation that’s hard to explain unless you’ve seen it up close, but this time felt different. Her friend Keegan Lyle later shared that in October 2016, Emma told her she was done, completely done. “Done for good” were the words she used.

Her family said the same thing. She had made a clear decision, and she meant it. What Emma didn’t fully realize is that someone who had spent years trying to control her might not just accept that and move on. Around that same time, Riley had been dropped from the football team at Maryville College. No team, no routine, no structure, just time. And a growing fixation on someone who had already said goodbye. And that raises a quiet, but difficult question. What happens when one person is ready to move on and the other refuses to let go?

What happened in the weeks between Emma’s final breakup and the night of November 21st, 2016, slowly took away her sense of safety. It didn’t happen all at once. It started with her phone. Emma had blocked Riley Gaul’s number, a normal, reasonable step after ending a relationship. But what she didn’t know was that he had found a way around it. He used an app called Phoner, something that could generate temporary anonymous phone numbers. So, the messages kept coming. Only now, they had no name attached, no face, no clear source, just texts appearing out of nowhere. At first, she wouldn’t have known who they were from, and that alone is unsettling because who do you even respond to when you don’t know who’s watching?

Then things escalated. One evening, Emma received a frantic message. It claimed that Riley had been kidnapped and left somewhere near the house she was visiting at the time. It sounded urgent, scary, the kind of message that makes you react before you even have time to question it. So, she went outside with her friend, Zach Green, and there, under a street light, they saw him, Riley Gaul, lying face down in a ditch. They rushed over. He lifted his head looking confused. He said he didn’t know what had happened, that he’d been taken, that he had no idea where he was. Zach would later describe it with disbelief.

Emma asked, “Why are you here?”

Riley responded, “I don’t know what happened.”

But Emma didn’t fully buy it. She had already ended the relationship. She had made that clear. And yet here he was, somehow appearing exactly where she was at that exact moment with a story that didn’t quite make sense. It raises a question you can’t ignore. Was that really a coincidence? She felt uneasy, but at that point, she still didn’t know how far things would go.

Then came something even more unsettling. Neighbors around the Walker family home started noticing a figure moving through the area at odd hours. Someone dressed entirely in black, quiet, watching. Surveillance cameras even caught glimpses of this person. It frightened Emma. She texted Riley about it, told him what people were seeing. He denied everything. He said he wasn’t there, that he didn’t know anything about it. And at one point, he even showed up as if he was there to protect her, as if he was the safe one in all of this. But later, a witness would point out something chilling. The man in black had been seen heading toward a community pool nearby, a place where Riley was known to park when he came into the neighborhood without being noticed. And when you put that together, it’s hard not to see it. Emma was being stalked by the same person who claimed to be protecting her from a stalker. It’s honestly disturbing to think about.

Emma was scared. Her parents were scared. The situation didn’t feel right, and they knew it. They tried to raise concerns, tried to get help, but there wasn’t much the system could do at that point. No direct threat, no clear crime that could be easily charged, just fear building slowly. And the person behind it all wasn’t done yet.

The night of November 20th, going into the early hours of November 21st, was cold in Knoxville. The Walker family home in Sterchi Hills was quiet. Emma had gone to bed. Her parents were asleep, the whole neighborhood quiet. Sometime around 3:00 a.m., Riley Gaul was outside the house. In the days leading up to that moment, he had taken a 9-mm Glock gun from his grandfather. He knew the layout of that house well. He had been inside it before, back when things were normal, when he was still welcome. He knew where Emma’s room was, and he used that. He fired twice through the exterior wall, straight into Emma’s bedroom. No one inside heard it. No shattered glass, no loud disturbance that woke the house, just two shots in the dark. One of those bullets went through the wall and struck Emma behind her left ear. The other lodged in her pillow. She was asleep. She never woke up, and that’s what makes it even harder to process. She never even had a chance.

The next morning, something felt off. Emma’s bedroom door didn’t open like it usually did. She didn’t come out for breakfast. At first, it didn’t seem like anything was wrong until someone went to check on her. They touched her foot. It was cold. They saw her lips turning blue. For a moment, they thought she might have been sick, that something medical had happened during the night, something natural, something explainable, but it wasn’t. It didn’t take long for them to call for help. Paramedics arrived, then detectives, and very quickly the truth started to come into focus. What looked like a medical emergency wasn’t one. Emma Jane Walker had been shot in her sleep.

Detective Chip Merritt and his team began speaking to everyone connected to Emma, her family, her friends, the people who knew her best, very quickly one name kept coming up. Riley Gaul. Again and again people pointed to him because of the relationship, because of how he had treated her, because of everything they had seen over the past 2 years. Almost everyone mentioned Riley and the way he had behaved toward Emma. So, investigators moved fast.

One of Riley’s closest friends, Alex McCarty, came forward with something important. He told detectives that Riley had taken a gun from his grandfather the weekend Emma died. When Riley was questioned about it, he denied everything. He said he hadn’t shown the gun to anyone, said he didn’t have it at all.

“Alex McCarty said that you showed him a handgun. Where is the gun?” a detective asked.

“I do not know,” Riley replied.

“You understand, no for us. Alex has no reason to lie about something like that.”

“Yeah, but I’m telling you, I don’t know where it’s at.”

But then he made a move that raised even more suspicion. He sent messages to his friends asking them not to talk to detectives about the gun and that said a lot because by that point some of his friends were already starting to question him. They had been watching how he acted, listening to what he said, and something didn’t feel right. They didn’t believe him. So, McCarty and another friend, Noah Walton, decided to go to the authorities. They wanted to help.

What happened next is honestly surprising. On the Tuesday night after Emma’s murder, less than 2 days after she was found, detectives set up a sting operation and they used Riley’s own friends to do it. McCarty and Walton were wired with microphones. Investigators could listen in live. There was even a small camera hidden in a key fob. Then they sent them to meet him. Riley had a plan. He wanted to get rid of the gun, throw it into the Tennessee River. Maybe in his mind that would erase the evidence. Maybe that would make everything go away. But it was already too late.

“Can we go to the bluff?” Riley asked. “That’s fine. ‘Cause I… I need to get rid of the gun.”

“At the bluff?”

“I’m going to throw it into the water. They will never… They’ll never even see it. Find it in the river.”

That night they went with him to the River Bluff Wildlife Area, a quiet overlook above the river. And as they got closer to the water, police moved in. They arrested him there. He still had the gun.

“Step out of the vehicle. Raise your hands up. Hands up all the way. Put the phone down. Put the phone down. Hands up all the way.”

“Sir, I don’t know what we’re about to do.”

Investigators also found gloves and black clothing, the same kind of clothing Emma had seen on the figure outside her home in the nights before she died. When you hear that, it all starts to come together in a way that’s hard to ignore. Riley Gaul was taken into custody.

In January 2017, a grand jury indicted him on multiple charges: first-degree murder, felony murder, stalking, reckless endangerment, tampering with evidence, possession of a firearm during a dangerous felony, and theft for taking the gun from his grandfather. Despite all of that, his family posted $1 million for bail, and he was released while waiting for trial. Which leaves a difficult thought sitting there. After everything that had already happened, how was he back out?

When prosecutors stepped back and looked at Riley Gaul’s actions in the weeks before Emma Walker’s death, a pattern started to form, and it wasn’t random. It was deliberate. First, he found a way around being blocked. He used an anonymous calling app so he could still reach her even after she had clearly tried to cut off contact. Then, he created a situation that would force her to respond, a staged kidnapping, a false emergency, something designed to pull her back in, to make her feel like she had to show up for him, and she did. After that, he started watching her, moving around her neighborhood at night, dressed in black, on foot, even after her parents had made it clear he wasn’t allowed anywhere near their home. Then, he took a gun from his own family, and in the early hours of November 21st, he used it. He fired twice into her bedroom at around 3:00 in the morning, aiming, prosecutors would later argue, at the exact place he knew she would be sleeping. And after all of that, he tried to get rid of the evidence. He involved his friends, people who didn’t yet know what he had done, and used them as part of that plan.

When the case went to trial, his defense explained why he tried to dispose of the gun. They said he was afraid of being wrongly linked to the crime, but the prosecution offered something much more direct. He wasn’t afraid of being connected to it. He already knew he was. And when you lay it all out like that, step by step, it raises a quiet but heavy question. Was any of this ever going to end any other way?

The trial of William Riley Gaul began on April 30th, 2018, in Knox County Criminal Court, in front of Judge Bobby R. McGee. It had taken over a year to get there. Part of the delay came from a request by the defense for more time to prepare. A request the judge approved. By the time the trial finally started, the courtroom was full. On one side was Knox County District Attorney Charme Allen leading the prosecution. Her husband, Assistant District Attorney Kevin Allen, would later deliver the closing argument. Behind him, on the wall, the jury could see a photo of Emma Walker smiling in her cheerleading uniform.

It’s hard not to think about that moment. A life frozen in one image while everything else being discussed was about how it ended. The prosecution built their case step by step. Their argument was clear. Riley intended to kill Emma. They said he acted out of anger after the breakup, that he knew the house well enough to know exactly where she would be. That the gun had been taken deliberately, and that the shot through the wall wasn’t random. It was aimed.

Kevin Allen told the jury that Emma had been shot and killed in the safety of her own home. And that detail stays with you, because home is supposed to be the one place where nothing like that happens.

The defense, led by Attorney Wesley Stone, didn’t deny that Riley fired the shots. That part wasn’t in question. What they challenged was intent. Stone argued that Riley hadn’t meant to kill her, that it was a reckless attempt to scare her, to create another situation where he could step in and rescue her. Similar, they said, to the fake kidnapping and the figure in black. He told the court that believing Riley intended to kill Emma would mean assuming he knew exactly where her head would be on the bed, down to that level of detail.

But the prosecution pushed back quietly. Riley had been inside that house. He had spent time there. He knew the layout. He fired twice, and one of those bullets struck a 16-year-old girl behind her left ear while she slept. And when you hear that, it’s difficult not to draw your own conclusion.

The trial included testimony that was especially hard to listen to. Jill and Mark Walker took the stand and described the morning they found their daughter. Friends spoke about the way Riley had behaved in the months leading up to it. The jury also saw body camera footage from the sting operation, real unfiltered video of him walking toward the river with the gun he planned to throw away.

Then, it was up to the jury. They deliberated. On May 8th, 2018, the verdict came back. Guilty. First-degree murder, felony murder, stalking, theft, possession of a firearm during a dangerous felony, tampering with evidence. As the words were read, people in the courtroom reacted. Audible gasps from the gallery. Riley, who had been out on bond during the trial, was taken into custody immediately. Outside, the people who loved Emma held onto each other. Charme Allen said it simply, the day was about justice for Emma and her family.

Under Tennessee law, a first-degree murder conviction carries an automatic life sentence. Riley Gaul received that sentence. He would not be eligible for parole for 51 years. Additional charges added more time, bringing the total to 60 years in prison.

At the sentencing, he chose to speak. He apologized to the Walker family. He said the shooting had been an accident, that he only wanted to scare Emma, not kill her. He said he was sorry for taking her away.

But Emma’s mother, Jill Walker, responded in a way that was direct and unwavering. She said he knew exactly what he was doing. He had been in their home. He knew where Emma slept. And when you hear that, it leaves very little room for doubt.

In June 2021, Riley Gaul filed a motion for a new trial. He argued that there wasn’t enough evidence. He also pointed to what he claimed were errors during the trial, issues with certain courtroom decisions. This included objections to a crime scene photograph being shown and to testimony about a video game, Call of Duty. Prosecutors had referenced it to explain something known as “wall banging,” the idea of firing through a wall at a known position. The motion was denied.

Then in February 2023, the Tennessee Court of Criminal Appeals reviewed the case. They upheld the murder conviction. There was a small adjustment to one of the lesser charges, but the main decision didn’t change. The court found no reason to overturn the verdict. So, the outcome stayed the same. Riley Gaul remains in custody at the Northwest Correctional Complex in Tennessee.

Emma Walker didn’t get the future she had planned. She never became the neonatal nurse she talked about. In Knox County, a dog park at Tommy Schumpert Park was renamed in her honor, the Emma Jane Walker Memorial Dog Park. Also, at East Tennessee Children’s Hospital, a room in the neonatal intensive care unit has been dedicated to her memory, the same kind of space she once hoped to work in. At Central High School, students created the Emma Walker Memorial Scholarship supporting those going into health care, continuing the path she never got to take. She was 16 with so much time and so many plans still ahead of her.