Lawyers for a man accused of killing two campers and burning their bodies have labelled the prosecution's case as "a shambles from start to finish".
Both sides began closing their cases before a Supreme Court jury in Melbourne on Tuesday, in the fifth week of the double murder trial of airline pilot Greg Lynn.
The 57-year-old is accused of murdering Russell Hill and Carol Clay, who disappeared while camping in Victoria's alpine region.
Lynn has admitted being involved in their accidental deaths, in March 2020, and destroying police evidence, but claims he is innocent of murder.
He told the jury Mrs Clay was killed after he and Mr Hill struggled over Lynn's shotgun.
The accused killer said he tried to get his gun off Mr Hill, who had taken it from Lynn's car after an argument over hunting.
Lynn claimed during the struggle a shot hit the side mirror of Mr Hill's ute and went into Mrs Clay's head.
He said Mr Hill then came at him with a knife and was stabbed in the chest during a second struggle, while Lynn was trying to defend himself.
But prosecutor Daniel Porceddu said Lynn's story was a made-up "series of unfortunate events".
"Like a book series of that name, it is a complete fiction," he told the jury on Tuesday morning.
"You can and should reject it beyond reasonable doubt."
He said Lynn's version of events, which he told police after his arrest in November 2021, deliberately pinned Mr Hill as the aggressor.
"Over the space of 24 hours, Mr Hill seemingly goes from cordial to homicidal rage," Mr Porceddu said.
He questioned Lynn's explanation that Mr Hill had taken a gun from Lynn's car to turn in to police with drone footage of the pilot shooting close to the Bucks Camp, in the Wonnangatta Valley.
"He's got the wrong gun," Mr Porceddu said, pointing out Lynn would have used a rifle to go hunting, but Mr Hill took a shotgun.
He queried why Mr Hill loaded the shotgun with ammunition, if his plan was to take it back to his campsite and hand it to police.
Further, Mr Porceddu said Lynn's explanation of the gun struggle, which included him demonstrating to police exactly how he was holding the gun, was "carefully choreographed".
"You might think it's because he's reciting a script, a script he's had one year and eight months to rehearse over and over again," he said.
"A script where position of the hands is very important, his hands can't be over or near the trigger when they're fighting over the gun."
He suggested Lynn had forgotten there was a rope stretching from Mr Hill's ute to the toilet tent, in coming up with his story.
"He and Mr Hill would have become hopelessly entangled in the rope," Mr Porceddu said.
Lynn has admitted burning the crime scene and taking the bodies of the two campers to a bush track, where he left their remains until returning to burn them in November 2020.
Mr Porceddu said Lynn wanted to "obliterate all evidence" about the manner in which they died, to conceal the alleged murders.
However, Lynn's barrister Dermot Dann KC told the jury the prosecution's case had been "a shambles from start to finish".
"What we have here is a prosecution case that's just unravelling. It's a pretty disgraceful spectacle," he said.
He claimed Mr Porceddu's closing address was "so desperate" it broke the court's rules for fairness during a trial.
"A prosecution case that has bumbled and stumbled its way out of the problematic category it started in, into the category of hopeless," Mr Dann said.
"A rule that's been in place for 130 years was breached time and time again."
He said Lynn had provided police with 1057 pieces of information and prosecutors had not proven that one of them was a lie.
He discussed 17 "lowlights" in the prosecution's case, including "half-baked theories" about ballistics and a failure to adduce evidence about Mr Hill's experience with firearms, or his character.
The defence closing address will continue on Wednesday.
