National News

Cold case killer unmoved awaiting sentence

Thirty-four years after Mary Louise Wallace's murder, her killer has sat impassively in court as her sister described her as a "beautiful, gentle person much loved by family and friends".

Robert John Adams, 64, will be sentenced on March 3 over the 1983 murder of Ms Wallace whose remains have never been found.

Adams was unmoved in NSW Supreme Court on Friday for the hearing, as Ms Wallace's two sisters read out victim impact statements.

"She was always happy and easy going and her life was taken from her in the worst of circumstances," Anne Fraser said.

"My life changed forever when I lost her.

"We want to be able to give her remains a final resting place, a duty we owe to our parents who went to their graves having grieved for 20 years."

Crown prosecutor Mark Hobart urged Justice Richard Button to take into account Adams' lack of remorse when considering a sentence.

"To not disclose the diseased's remains is evidence that the offender is extremely callous," he said.

Adams' lawyer told the court he is unlikely to re-offend due to his age.

Adams was found guilty in November of murdering Ms Wallace, who was 33 years old at the time.

She was last seen with Adams in his car leaving a Crows Nest bar, on Sydney's north shore, in the early hours of September 24, 1983.

The court found the former carpenter had choked or strangled Ms Wallace to death with the intention of having sexual intercourse with her without consent.

Justice Button said during the trial Adams had a "chronic" tendency to rape and strangle women after luring them to his car - something he'd done to at least three other women.

"The accused treated the deceased very much like an object," he said.

It took 30 years for Adams to be arrested, after hairs seized from his car boot were matched to strands from Ms Wallace's hairbrush.

Adams will appear via video link for sentencing.

© AAP 2017