The murder trial included home surveillance footage of the girl firing the gun
Carly Gregg, the teenager who fatally shot her mother and attempted to kill her stepfather, was sentenced to life in prison Friday.
The jury in Rankin County, Mississippi, found Gregg, 15, guilty on all counts, and prosecutor Kathryn Newman said Gregg had shown "zero remorse."
The teen was charged with murder and aggravated assault in the March 19 shooting that killed her mother, 40-year-old Ashley Smylie, and wounded her stepfather, Heath Smylie. She was also charged with tampering with evidence for hiding a security camera after the shooting.
On the first and second counts, Gregg was sentenced to life in prison. On the third count, she received 10 years.
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During her initial court appearance, Carly Gregg pleaded not guilty to the charges. Her bond was set at $1 million. She is being held in the Rankin County Adult Detention Center. (Rankin County)
The ruling came after a week-long deliberation into the shocking murder of Smylie inside the family's home.
The encounter was recorded on the family's kitchen surveillance camera, which was shown in court Wednesday. The shocking footage showed the 14-year-old's seemingly nonchalant attitude as she took a .357 Magnum handgun to her mother's room and shot her.
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In the video, Gregg is seen texting her stepfather in an attempt to lure him home and ambush him.
When Heath Smylie took the stand Tuesday, he testified that when he opened the kitchen door, "the gun went off in my face before the door was even three to four inches wide open, and everything kind of went pretty fast from there."
"The gun flashed in my face," he said. "It went off two more times, but my hand was on the gun after the first shot, and I twisted it from Carly." Heath was shot in the shoulder during the encounter with Gregg, police said.
The footage showed Carly Gregg moments after she allegedly opened fire and killed her mother in March. (YouTube/Law & Crime Trials)
During the trial, Gregg's defense attorney did not deny the teen had killed her mother but attempted to prove the teen was suffering from a mental health crisis and did not remember the shooting.
The five-day trial included expert witnesses and provided insight into Gregg's mental state.
"Dr. Clark, based on your experience, expertise and evaluation of Carly, do you believe that Carly was able to understand the nature of her conduct and appreciate the difference between right and wrong at the time this incident occurred on March 19?" defense attorney Bridget Todd asked Dr. Andrew Clark, a child and adolescent psychiatrist based in Cambridge, Massachusetts.
"I don't think so," Clark said.
Carly Gregg in kitchen surveillance footage moments after she allegedly shot and killed her mother. (YouTube/Law & Crime Trials)
In closing arguments Friday, prosecutor Michael Smith zeroed in on the damning security footage, saying Gregg "knew what she did."
"Ladies and gentlemen, there’s no doubt Carly Madison Gregg is the one who killed her mom, Ashley Smylie. There’s no doubt that she attempted to kill Heath Smylie, when she aimed the gun right at his head and shot and hit him. And there’s no doubt that she’s the one who hid the camera, thus tampering with evidence," he said.
"She knew exactly what she was doing, and she knew the difference between right and wrong."
— Prosecutor Michael Smith
"We would ask that you go back there, and you find her guilty of all three, because she was not insane at the time that this happened," he said. "She knew exactly what she was doing, and she knew the difference between right and wrong."
Sarah Rumpf-Whitten is a breaking news writer for Fox News Digital and Fox Business.
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