‘Not going down for this’: Accused child-killer’s denial

After being charged with murdering his fiancée's daughter, Justin Laurens Stein told corrections officers it was actually the girl's mother who had killed the nine-year-old during an ice binge.

Stein, 33, is standing trial for murder in the NSW Supreme Court over the death of schoolgirl Charlise Mutten, whose body was found in a barrel by the Blue Mountains' Colo River on January 18, 2022.

While being processed into Sydney's Silverwater jail the day after the body was recovered, Stein was asked by a corrections officer, "Did you do it?"

An emotional Stein claimed to be innocent and said he had witnessed the girl's mother, Kallista Mutten, shoot her daughter, the jury heard.

"Her mum was on ice all week," Stein said, according to the officer.

"I heard a shot and then I heard her screaming out for me. Then I ran back and she shot her again.

"I keep having flashbacks. I'm not going down for this.

"I've been trying to tell people this for days and no one would listen. Thank you for letting me vent."

Mutten was in a relationship with Stein at the time and the pair had planned to get married, the jury previously heard.

The corrections officer, Stacey Sweeney, told the trial today that "nine out of 10" inmates she met pleaded their innocence.

Police approached Sweeney afterwards to ask if Stein had said anything to her during the interview, which she described as highly unusual.

Stein gave his mother Annemie the same account in phone calls from prison, which were recorded and played for the jury.

"The last thing she screamed was my name and then you heard 'mummy no' and then the second gunshot," he told his mother.

Stein said she believed her son, but she questioned why he did not call police and why he was later tracked driving to several locations across Sydney, allegedly with the barrel containing Charlise's remains on the back of his ute.

"I just can't work out the barrel," she said.

Stein claimed in the recorded phone call that Mutten had put the barrel with the remains on the back of the ute without his knowledge and only informed him of it later while he was out driving the vehicle.

"Is that why you drove around for five hours?" Stein asked.

"Yes, I f—— panicked," he said.

After finding the barrel containing Charlise's body using location data from Stein's phone, police tracked him to a unit in the inner-Sydney suburb of Surry Hills and arrested him.

Police informed Stein of the evidence against him, which included phone data and CCTV footage that captured him travelling with a boat – and allegedly with Charlise's remains in the barrel – to several launching ramps across Sydney.

In an interview with police on the day Mutten reported her daughter missing, Stein initially claimed to know nothing about the girl's disappearance.

Hours later, after police pressed their concerns over aspects of Stein's account, he told officers he believed Mutten was behind the disappearance.

Stein said it might have been for custody reasons as Charlise had lived full-time with her grandparents from around the age of four.

The trial continues.