'Star' daughter mourned after brutal drug dealer murder

A mother has remembered a kind and generous daughter fatally bludgeoned in Sydney bushland while one of her killers has said his drug dealer boss was behind the murderous plan.

Namja Carroll was taken to a remote part of Sandy Point in the city's southwest by Benjamin Troy Parkes and Robert Sloan on July 14, 2020 before she was killed with a baseball bat, doused in petrol and burnt.

The 33-year-old's body was discovered by a bushwalker 15 days later.

Sloan pleaded guilty to the murder in January this year while Parkes denied the offence but was found guilty by a NSW Supreme Court jury in April.

The pair were heavy users of the drug ice at the time of the brutal killing.

On Friday, Sloan wore a black shirt and black suit during a sentence hearing where Anne Carroll read out a statement mourning her daughter while also remembering her life.

"She was a bright, positive, shining star in my life," she told the court.

"Her name, Najma, means 'star' in Arabic."

During school she was gifted academically and in sports, playing a role in the formation of her high school's first ever soccer team.

However, due to abuse as a teenager - which she only revealed to her mother in her 20s - she spiralled into drug use and dependency, the court was told.

"The light of Najma's shining star has been extinguished but Najma's spirit of courage, resilience and fortitude in support of truth, justice and equality lives on in all of us," her mother said.

Crown prosecutor Darren Robinson said there was an extreme level of violence after Sloan and Parkes planned the murder.

He said the pair had formed this agreement by July 11 when they started removing their victim's belongings from a room at the Hunts Hotel in Liverpool where they all were staying.

While forensic analysis indicated Ms Carroll received multiple blows before her death, there was no way to tell whether Parkes or Sloan had inflicted the fatal wound, Mr Robinson said.

The motives for killing Ms Carroll were that she knew too much about their drug business and wanted money she had invested into their activities returned, he told the court.

Sloan will ultimately receive a discount to his sentence because of his guilty plea.

His barrister Madeleine Avenell SC argued that the 61-year-old's crime was less serious than Parkes' because he was a subordinate and not the leader of their drug business.

"Mr Parkes was the dominant force and Mr Sloan was the lieutenant or the doer," she said.

Ms Avenell disputed that Sloan had formed a plan with Parkes for the murder by July 11, arguing that this only occurred later.

She described the motives put forward by prosecutors as "nebulous".

This was contested by Justice Natalie Adams who pointed out the paranoia that ice could create.

Sloan's time in custody would be more onerous because of a shotgun wound he had previously suffered and age-related heart conditions, Ms Avenell said.

He was also in protective custody at Shortland prison in Cessnock after being assaulted in September.

Justice Adams will sentence Parkes next Friday before sentencing Sloan on August 2.