On a chill-touched Monday morning in November 2016, Jill Walker went to wake her teenage daughter.

It was earlier than usual. Emma Walker, a 16-year-old high school cheerleader, wanted to wash her hair — and there was a lot: vast blond Rapunzel locks. At 6:15 a.m., Jill Walker stepped through her family’s single-story home in a picture-book subdivision in Knoxville, Tenn. Her daughter, as she would later tell a jury, was independent, fun-loving and kind, a teenager who enjoyed animals and hoped one day to become a neonatal nurse.

But the last weeks had been trying. The household was tense; teenage drama had soured into something menacing. Over the weekend, Emma had asked her parents to activate the house’s security system. She had never made such a request before.

Emma was lying face up on the bed when Walker touched her leg. No response. “Emma,” the mother said. Still no response.

After moments of trying to pull Emma back to consciousness, Walker dialed 911. While she waited for help, Walker did not notice two bullet holes pocking the bedroom’s wall.

Law enforcement officials would eventually determine that Emma had been killed in her sleep, shot with a 9mm handgun in the early hours that morning. The community around Central High School and greater Knoxville were pitched into grief. Five days later, students and families wore purple armbands in Emma’s honor at Central High’s next football game, the Columbia Daily Herald reported.

The confusion and grief over a classmate’s death deepened shortly after the shooting when police arrested and charged a suspect: William Riley Gaul, an 18-year-old former Central High football standout then attending Maryville College in Tennessee. According to authorities, Gaul killed Emma after the teenage romance devolved into a desperate obsession.

And as Gaul’s trial unfolds this week, the defendant’s attorneys are not arguing whether Gaul pulled the trigger. He did — but it was not a premeditated killing, the defense claims. The shooting was a stunt to win back Emma that went horribly wrong.

“Mr. Gaul committed the offense of reckless endangerment with the hope of coming to her rescue, of being her hero,” defense attorney Wesley Stone told jurors this week, 10 News reported.

The relationship between Emma and Gaul began when the cheerleader was a freshman at Central High School. Gaul was two years older.

“In the first couple months, it was fine,” Jill Walker testified this week. “It seemed normal. We kept a close eye; she was only 14 years old at the time.”

According to Walker’s testimony, Emma’s parents eventually began to get bad signals from their daughter’s older boyfriend. “It was winter of 2015. I guess he started going back to his ex-girlfriend,” the mother told the court. “There was some things going on where he was playing them both.”

The parents also monitored their daughter’s text messages and Snapchat account. Walker told the court they did not like the tone Gaul took with Emma. “Some of the language and the way she was spoken to, we didn’t think it was appropriate — to speak to anyone like that,” she said. “We tried to discourage her from seeing him. We would set limits how and when they could see each other.”

When Gaul left for college, the parents hoped the distance would finally cool the relationship. But Emma was “stubborn,” her mother told jurors, and continued to see Gaul in an on-again, off-again way until fall 2016. Then the couple allegedly made a final split.

“She had chosen to move on,” Jenny Weldon, Emma’s aunt, told the court this week. “He refused to accept it. He chose not to accept her wishes.”

But on the weekend of Emma’s death, an odd series of events underscored just how bizarre and toxic the relationship had become.

On the Friday before the Monday killing, Emma was at a friend’s house celebrating a Central High football victory. Her phone began buzzing with texts from a number she didn’t know. The person on the other end said they had kidnapped someone she knew and needed her to come outside alone.

“Go to your car with your keys,” the text read, according to the Knoxville News Sentinel. “Go alone. … I’ve got someone you love. If you don’t comply I will hurt them.”

“We have him now,” another text read. “If you don’t care about him anymore then it shouldn’t bother you. Call the police, and he dies. Your choice. … If you’d like to hear his final screams, give me a call. He’s in a ditch beside [the] house. It’s a shame you can all of a sudden not value someone’s life.”

When Emma and her friends stepped outside, they discovered Gaul on the ground nearby.

“He told me he was hit over the head, and he didn’t recall anything,” a friend who was there testified this week. “But then later he remembered [the kidnappers] said, ‘Call Emma.’ I told her it was probably made up. It was the type of behavior he’d exhibited before.”

The next day, while Emma was at home, a man dressed all in black and with his face covered knocked on her door when she was alone. Terrified, she called Gaul to come for help. Again, her friends allege the ex-boyfriend was the disguised intruder. The prosecutor alleged this week that Gaul pulled both stunts to curry sympathy with Emma and scare her into turning back to him for support.

Gaul’s attorney maintains that the shooting was the third stunt. Sometime in the night, the football player crept into the Walkers’ fenced back yard, again wearing black clothing. Using a pistol he had stolen from his grandfather, he fired twice into the home. He did not intend to kill anyone, the defense argued, only to again scare Emma back into his arms. He would be her “hero,” the defense claimed.

“[First-degree] murder requires an intent to kill,” Gaul’s attorney told jurors, the Associated Press reported. “Some of us who are familiar with handguns may very well know that by shooting into a wall blindly, it will go through a wall. Some of us may not.”

Authorities, however, allege that Gaul knew exactly what he was doing. “He knew where she was when he shot through the house,” Knox County Sheriff’s Office Major Michael K. MacLean told reporters after the arrest, according to the News Sentinel.

The gunfire woke Emma’s father, the paper reported. Mark Walker testified this week that he had thought it was a slamming door. He paced through the home to check, peering into his daughter’s bedroom. In the darkness, she appeared to be asleep. He did not realize the teenager was bleeding out from a gunshot wound.

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