SA cold case killer jailed for 15 years

A man who bludgeoned a friend to death with a metal bar almost 20 years ago has been jailed for at least 15 years for murder.

Adrian Stewart Mahony, 67, killed Dale McCauley at the victim's home at Willunga, south of Adelaide, in January 1998 before burying his body in scrub nearby.

In what was one of South Australia's most baffling cold cases, the 44-year-old's remains were only found in January last year, after Mahony was arrested.

A video plea from the dead man's sister, which was shown to Mahony in detention, prompted him to then disclose the isolated location at Rapid Bay where he had left the body.

Passing sentence in the Supreme Court on Thursday, Justice Malcolm Blue said that allowed closure for Mr McCauley's family in circumstances where the dead man's body might otherwise have never been found.

He said Mahony's guilty plea also avoided a trial, in what was a largely circumstantial and relatively weak prosecution case.

In sentencing submissions last month, prosecutor Carmen Matteo said the attack on Mr McCauley was "brutal" with Mahony striking him multiple times in the head with a metal bar.

She said the killer had wielded the bar in two hands and had attacked from behind.

The murder was prompted by Mahony's anger at his friend's decision not to go ahead with a plan for the pair to restore a boat and move to Queensland to start a business together.

Defence counsel Mark Griffin told the court Mahony lost his temper and self-control for just a "minute or two" when he struck the victim causing the fatal injuries.

Mr Griffin said Mahony was now suffering from prostate cancer and asked Justice Blue to consider imposing a minimum term that might allow him to finish his days outside prison.

The judge jailed Mahony for life but set the lower 15-year non-parole period.