A Harris County jury began deliberating Wednesday in the trial of a teenage girl charged with killing her father.

The girl was 12-years-old when prosecutors said she shot and killed her father while he was asleep in their Katy home in April 2009.

Prosecutors argued that the girl, who is now 15, was mad at her father for disciplining her, but the defense said that the girl was keeping a secret.

"The physical and verbal and emotional and sexual assaults were getting more and more aggravated as time went on," defense attorney Windi Akins Pastorini said.

According to courtroom testimony, the girl's father began abusing her when she was 6 years old.

Defense attorneys argued that she had no choice but to shoot and kill her father.

"She was clearly defending herself that morning. He had threatened her. He had come into the bathroom where she was bathing. She had tried to cover herself. For the first time in 12 years, she stoop up to him and she screamed at him to get out," said Pastorini.

Prosecutors argued that the girl never asked for help. The girl didn't tell the investigating officers about the abuse, instead saying she and her father argued and struggled over the gun, according to courtroom testimony.

"If she had waited until he was awake, he would have overpowered her like he always did," said Pastorini.

At the time of the shooting, Children's Protective Services was looking into a claim that the girl was being abused.

"We have testimony about black eyes, busted lips, welts on her body," said Pastorini.

CPS was also looking into an allegation that the father tried to choke the young girl. Reports showed she had marks on her neck.

The jury asked for three pieces of evidence, including testimony and the girl's school attendance reports.

According to courtroom testimony, the father pulled the girl out of school early one day for a lengthy day of abuse.

The girl faces 40 years in prison if convicted.