Greg Lynn found guilty of murdering Victorian camper Carol Clay ...

Former Jetstar pilot Greg Lynn has been found guilty of murdering retiree Carol Clay at a Victorian campsite four years ago, but a jury has acquitted him of murdering fellow camper Russell Hill.

The pair was last seen alive during a camping trip in the Wonnangatta Valley, about five hours east of Melbourne, in March 2020.

Lynn was arrested more than a year later and charged over their deaths.

He pleaded not guilty in Victoria's Supreme Court, but during his five-week trial admitted to destroying evidence and burning the pair's remains.

Greg Lynn's lawyers argued the deaths of Russell Hill and Carol Clay were tragic accidents.(Facebook)

The case generated huge media interest during the two-year investigation into the campers' disappearance, and then during Lynn's Supreme Court trial. At times the court's public gallery was so full, people had to stand or were turned away.

With no eyewitnesses, the case boiled down to two competing theories about what happened at a remote location named Bucks Camp.

Prosecutors argued Lynn killed the retirees with murderous intent — likely killing Mr Hill first, then shooting Ms Clay, possibly following a dispute over a drone.

They argued Lynn's "disproportionate" actions to contaminate the crime scene and dispose of the bodies was "incriminating conduct" that pointed to murder.

However, Lynn's lawyers described a scenario of two tragic, accidental killings.

Defence barrister Dermot Dann KC argued Ms Clay was fatally wounded as Lynn and Mr Hill wrestled over a shotgun, which discharged and fired a projectile that struck her in the head.

Mr Hill was then killed when he came at Lynn with a knife and fell to the ground, with the blade going through his chest, Mr Dann said.

Lynn took to the witness box in the trial, and conceded his decision to dump the bodies and set them on fire was "despicable".

"All I can say to their families is that I'm very sorry for your suffering," Lynn said.

Lynn remained emotionless as the jury foreperson read out the two verdicts in the case.

Throughout the trial, Lynn was supported in court by his wife, Melanie, and son, Geordie.

Lynn's son Geordie was sitting in the courtroom, his arms crossed, looking despondent but Melanie did not appear to be in the courtroom when the verdict was handed down.

Lynn's final words before he was taken into custody were to his son. "Don't stress," Lynn told him.

Family of Mr Hill were also in the courtroom as the verdict was handed down.

Mr Hill was a retired logger and high-frequency radio enthusiast who regularly visited the Wonnangatta Valley, while Ms Clay was a former Victorian Country Women's Association president.

The pair had once been childhood sweethearts, and Mr Hill kept their affair secret from his wife.

Police found Russell Hill's four-wheel-drive and burnt possessions at the campsite after Mr Lynn took the bodies away.(Supplied: Victorian Supreme Court)

The trial was told Lynn only crossed paths with the retired campers the day before the deadly incident on March 20, 2020.

Lynn later told police the conflict began because Mr Hill was unhappy he had been hunting near the campsite, and threatened to take footage from his drone to the police.

Lynn claimed he then blasted loud music from his car in an attempt to annoy Mr Hill. The former pilot then claimed Mr Hill stole his shotgun and fired a warning shot into the air.

A physical struggle over the gun occurred when Lynn tried to snatch the weapon back, he told police.

Lynn said he feared nobody would believe the two deaths were accidental, so he decided to try to hide his involvement to protect his aviation career, family and sporting club memberships.

He torched the campsite, put the bodies in his trailer and dumped them next to the remote Union Spur Track.

Police were eventually able to link Lynn to the campers' disappearance when his vehicle was snapped on a roadside traffic camera near Mount Hotham.

The Barathrum Arms shotgun owned by Greg Lynn, which he said accidentally discharged at the campsite.(Supplied: Victoria Police)

In the months that followed, detectives closed in on Lynn, who returned to the burial site and torched what was left of the decomposing remains.

When forensic experts turned up to Union Spur Track in November 2021, after Lynn's arrest, they discovered more than 2,100 skeletal fragments.

Pathologists said they could not determine a cause of death because the remains had been so badly "obliterated".

Lynn later told police: "I'm innocent of murder. I haven't behaved well. I've made some poor decisions, but murder as I understand it, I am innocent of."

At the end of the trial, prosecutors told the jury to reject Lynn's story, saying it was an elaborate lie and a "complete fiction".

After weeks of evidence, Lynn's lawyers pointed to perceived flaws in the case against him, saying prosecutors were unable to point to a clear motive or even outline the order in which the alleged murders occurred.

A sketch of Greg Lynn in the Supreme Court.(Artist: Paul Tyquin)

Lynn's barrister Mr Dann called the prosecution case "hopeless" and said it was based on "half-baked theories".

Following the verdict, Victoria Police Assistant Commissioner Martin O'Brien acknowledged the jury's decision.

"Our thoughts are with the Hill and Clay families at this time and we acknowledge how difficult these past four years have been for them," he said.

"Their courage and resilience in the face of their grief, amidst enormous public attention, has been nothing short of extraordinary. We will continue to support them in every way possible following this decision."

The matter will return to court on Friday July 19, as the case enters its next phase, which is the sentencing process of Lynn.

A person in Victoria found guilty of murder faces a maximum penalty of life in prison, with the standard sentence 25 years' jail.