Peter Keeley murder trial hears differences in expert testimony may be grounds for acquittal

Forensic experts disagreed on several key points, including Mr Keeley's cause of death. (Supplied: NSW Police)

A judge has been asked to acquit two teenage boys accused of murdering a Canberra man in 2020 due to "significant differences" in expert witness evidence.

Today the defence gave its closing statements in the New South Wales Supreme Court trial of two young men accused of murdering 56-year-old Peter Keeley in bushland at Broulee on the Far South Coast.

The two boys, now aged 19 and 20, pleaded guilty to aggravated kidnapping and not guilty to murder.

Mr Keeley's body was found with tape around the ankles, wrists and head.

Earlier in the trial the court heard one of the accused spoke to Mr Keeley on a dating app before he was found dead, and that another thought he was a paedophile.

On the final day of the trial, defence barristers Clive Steirn and Carolyn Davenport argued the key prosecution witness did not present reliable evidence.

The defence has argued that methamphetamine toxicity caused Mr Keeley's death.

The 56-year-old was found dead in this stretch of bushland in Broulee on February 2, 2020. (ABC South East NSW: Holly Tregenza)

Forensic pathologists Bernard I'Ons and Johan Duflou disagreed on several points, including whether Mr Keeley's airways were obstructed before his death and what his cause of death was.

In his evidence for the prosecution, Dr I'Ons told the court Mr Keeley likely suffered cardiac arrest caused by a craniofacial trauma with airway obstruction after the teenagers assaulted him.

But defence witness Dr Duflou argued that the drugs in Mr Keeley's system could have contributed significantly to his death.

The court previously heard that drugs and drug paraphernalia, including cannabis, methamphetamine and two syringes were found in Mr Keeley's car.

In his closing statement, Mr Steirn said Dr Duflou had worked as a forensic pathologist for 39 years, while Dr I'Ons had worked in the profession since 2016.

Mr Keeley's body was found near Broulee, a small town on the New South Wales far south coast. (ABC South East NSW: Holly Tregenza)

Mr Steirn also said the court should take a "cautious" approach in assessing the prosecution's forensic evidence.

"The Crown case is a dangerous one," he said.

Mr Steirn said if Justice Michael Walton was unable to resolve the conflict between the evidence given by Dr Duflou and Dr I'Ons he must acquit the accused on the charge of murder, because it would show the case could not be proven "beyond a reasonable doubt".

Justice Walton told the court he expected to deliver his verdict in approximately three weeks.