The girl was a year too young to face the maximum penalty of 40 years' confinement, said Juvenile Prosecutor Phil Garrett.
The girl's boyfriend who is the alleged shooter, James Michael Lee Chesnut, 18, has been arrested but not yet indicted in connection with the shooting.
The victim, Karen Duke, testified that she was shot while sleeping on the couch of her Mineral Wells home and then ran to the master bathroom. Duke, 38, said she could have died from a gunshot wound to the chest and back that left her hospitalized for a week.
A Mineral Wells firefighter testified that after Duke was in the ambulance, she said her daughter's boyfriend shot her.
Duke's daughter had gunshot residue on her clothing, according to an investigator. But in a statement to police, the teen denied shooting her mother or leaving a window open so someone could enter the house.
The teen said Chesnut had walked her home that night and had a gun. She said she later realized that someone was in the house and hid in the bathroom, according to her statement read in court.
Investigators said her statement did not match the evidence.
A friend of Chesnut's testified that the girl talked about paying her boyfriend $500 to shoot her mother but never did. Other evidence presented were lists the teen had written, including the pros and cons of killing her mother and ways to do so, Garrett said.
The defense attorney, Kerry Dobbs, had asked for probation. The teen's grandmother testified about the girl's recent obedience. The girl did not testify during the trial.
After the verdict Tuesday, Duke said in her victim's impact statement that she has rarely left her home since the shooting because she is afraid of her daughter and her boyfriend, and "I don't want my other daughter around her. I don't feel safe in my own home."
Three weeks before the shooting, Duke called police after reportedly finding her daughter in bed with Chesnut, and he later was arrested on a charge of sexual assault of a child. Chesnut, of Mineral Wells, was jailed Friday on a drug charge. Chesnut does not have an attorney, according to the Palo Pinto County District Attorney's Office and Palo Pinto County Jail.
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