Mother, son show 'no remorse' over cop's death

A mother and son charged with the murder of Detective Inspector Bryson Anderson showed "no remorse" over his death, court documents allege.

Fiona Barbieri, 45, and Mitchell Barbieri, 19, chose not to appear in Penrith Local Court today.

The pair has been charged with the stabbing murder of Det Insp Anderson, 45, who was killed during an alleged neighbourhood dispute yesterday in Sydney's north west.

He was one of many officers who went to the scene in Scheyville Road, Oakville, near Windsor.

The court was told that police have applied for a forensics procedure on Mr Barbieri, which will include DNA testing.

The mother and son did not apply for bail which was formally refused and they will appear in the same court on December 14.

Court documents state they showed "no remorse" and denied murdering Det Insp Anderson when police charged them.

"The accused show no remorse and a total denial of the offence," the court documents for Mitchell Barbieri state.

"He displays a total disregard for the law and is a real risk to the safety of the community should he be released on bail."

The court documents state similar reasons for Fiona Barbieri, saying she was in "complete denial" and had a "complete disregard for the law".

Police Commissioner Andrew Scipione says Det Insp Anderson died following a knife attack, contrary to reports that he was killed with an axe or a bow and arrow.

"We will be alleging that a knife was used in this attack," Mr Scipione told reporters in Sydney.

"A knife was used and led to the death."

Mr Scipione praised the efforts of paramedics and police who tried to save Det Insp Anderson's life before he was declared dead at Hawkesbury Hospital.

"I am sure (they did) all that was humanly possible to save his life," he said.

He would not indicate if Det Insp Anderson died at the scene.