Charlise Mutten died in 2022. The 9yo's mother has been accused in court of fatally shooting her.

Kallista Mutten broke down in tears when confronted with accusations she killed her own daughter, telling a court she didn't even know exactly where the nine-year-old had been shot.

Justin Stein, 33, on trial for the murder of schoolgirl Charlise Mutten, claimed he witnessed Ms Mutten shoot the girl.

Charlise's body was found by police in a barrel by the Blue Mountains' Colo River on January 18, 2022 with gunshot wounds to her face and back.

Watch: Justin Stein's murder trial has begun. Post continues after video. 

At the time, Ms Mutten was in a relationship with Stein and the court previously heard the pair had plans to get married.

Stein's lawyer, Carolyn Davenport SC, in the NSW Supreme Court on Tuesday put to Ms Mutten that on January 12, 2002 she fatally shot Charlise at the Blue Mountains property where she was staying with Stein.

"What I suggest is... you had, in fact, shot and killed your daughter," Ms Davenport said.

"Are you serious?... No," Ms Mutten said.

"You shot her once in the back and once in the head," Ms Davenport said.

"I didn't even know she was shot with a gun," a distraught Ms Mutten replied.

"I didn't even know where she was shot, so now I know."

At that point, the court adjourned to allow Ms Mutten to compose herself.

Charlise Mutten. Image: Supplied by Tweed Heads Public School.

Ms Davenport told the jury during her opening address it would become apparent Ms Mutten, not Stein, had a motive to kill the girl.

Charlise, who lived with her grandparents, had been visiting her mother and Stein over the Christmas holidays. During the visit, the group spent their time between a Mount Wilson property owned by Stein's mother and a caravan at the Riviera Ski Park, about a 90-minute drive away.

During her evidence on Monday, May 27, Ms Mutten told the trial she saw her daughter for the last time on January 11, when the nine-year-old travelled alone to spend the night with Stein at Mount Wilson while she remained at the caravan park.

Ms Davenport put to Ms Mutten on Tuesday she had actually seen Charlise alive on January 12 and the girl had travelled with her and Stein to Sydney, which she denied.

Ms Mutten admitted lying to police about Stein's drug use and access to firearms in the weeks after her daughter's body was discovered. She told the court Stein had said not to reveal the truth about their drug use, including his consumption of methamphetamine, which they had sometimes used together.

Ms Davenport questioned why she would lie for Stein at a time when she knew Charlise's body had been found and he was charged with her murder. 

"I still in my heart believed that what he told me was the truth," Ms Mutten answered.

Charlise Mutten. Image: NSW Police.

She admitted to using drugs during Charlise's visit, but denied using them in front of her daughter. She said that, at the time, she and Justin were "fighting a lot" and she had chosen most days to stay at the caravan rather than the Mount Wilson property.

Ms Davenport put to her that Charlise preferred to stay with Stein and his mother at Mount Wilson rather than with her

"You're comparing, like, a caravan to mansion," Ms Mutten said.

"[Charlise] asked you if she could go back to Mount Wilson, and you allowed it," Ms Davenport said.

"Unfortunately, yes," Ms Mutten said.

She agreed methamphetamine use had caused her a lot of problems in her life and that she had continued using it despite it occasionally causing drug-induced psychosis. One episode forced the cancellation of a planned visit by Charlise over Easter 2021 to visit Stein and Ms Mutten, when she was hospitalised after being found incoherent in the middle of a road.

"You were taking ice despite the fact that your daughter was due to arrive to see you in a few days?"

"Yes," Ms Mutten said. 

The trial continues.

— AAP. 

Feature Image: Tweed Heads Public School.