Courtroom twist as accused killer Greg Lynn is set to go into the witness box and plead his innocence over the alleged double murder of elderly secret lovers

Former Jetstar pilot Greg Lynn will allow himself to be cross examined under oath after making the decision to give evidence in his murder trial.  

Lynn, 57, has pleaded not guilty in the Supreme Court of Victoria to the murders of Russell Hill, 74, and Carol Clay, 73, in the Wonnangatta Valley, in Victoria's Alpine region, on March 20, 2020.

On Wednesday, the last of the prosecution witnesses, Missing Persons Unit detective Brett Florence, was cross examined by Lynn's barrister Dermot Dann, KC. 

But on Thursday, Lynn will enter the witness box to give his version of events, in person and in his own words. 

Sergeant Florence and his partner Daniel Passingham had grilled Lynn over the alleged murders at Sale Police Station on November 23, 2021.

The jury was presented a little over three hours of that interview this week, in which they watched Lynn recall how he claimed the campers died and the efforts he made to conceal their bodies. 

Mr Dann ran Sergeant Florence through each and everyone of those claims on Wednesday, asking each time if the evidence obtained by police supported what Lynn had told them. 

Again and again, Sergeant Florence responded in the affirmative. 

'Mr Lynn answered every question asked of him, is that correct,' Mr Dann asked. 

'Yes,' came the response. 

'He marked every map that was provided to him, is that right? He marked every photo that was provided?' Mr Dann asked. 

'Yes,' Sergeant Florence responded. 

'He assisted you in locating the site where the bodies had been taken and burnt, is that agreed?' came the question. 

'Yes,' the detective said.  

The process of confirming the facts went on in court for the next hour. 

The jury heard not only did Lynn's account of what he told detectives match what they would later determine true themselves, but he supplied them with information they had no idea even existed at the time. 

Until Lynn's interview, detectives had no idea blood splatter from Ms Clay could be located within the rear canopy of Mr Hill's Landcruiser. 

'Not even you knew of the location of blood splatter or human tissue inside the canopy attached to his vehicle,' Mr Dann said. 

'No, I didn't,' Sergeant Florence said. 

The video recording of Lynn's police interview showed the pilot dressed in a grey windcheater, spectacles and surgical mask as he recalled the fateful night police claim he murdered the pair. 

Footage showed his lower half wrapped-up in a doona due to the extreme cold within the police interview room. 

The jury has heard evidence from various witnesses who were in the bush when Lynn and the campers were there. 

Many told near identical versions of events offered up by Lynn to police during his record of interview. 

The jury heard Victoria Police's own ballistics expert agreed Lynn's story about how Ms Clay was shot dead appeared accurate. 

'The shot going through the mirror, Ms Clay in a position where her head is around 110cm region ... you're aware (your expert) said that all of that in terms of Mr Lynn's version, or that version - that collection of circumstances - was absolutely spot on,' Mr Dann said. 

While Sergeant Florence claimed to have no idea about his own expert's findings, he reluctantly agreed he was probably right. 

'I didn't know that he'd given that evidence. I thought the tests were inconclusive. I didn't know he'd used the words "spot on",' Sergeant Florence said. 

'If he says that it's spot on, well yes, he's an expert and we'll take his word for it.'

Lynn told the detectives he had become involved in a deadly fight with Mr Hill as they fought for control of a shotgun when it went off and killed Ms Clay.

The jury heard Lynn approached Mr Hill when a scuffle over the firearm took place.

'I confronted him. "Give it back. What are you doing", and he said he was going to take that to the police with him,' Lynn said.

'Then when I advanced towards him, he had the magazine in the shotgun at this stage, he pulled the action back and he let a couple of rounds go into the air.'

Lynn claimed he ran for his life before creeping back upon Mr Hill from the shadows.

'I kept under the shadow and I moved in closer,' Lynn said.

'To try and disarm him, I jumped-up, I grabbed the shotgun barrel with my right arm, pivoted around so that I was facing him... I had the left hand on the stock, right hand on the barrel, and we wrestled.

'The shotgun was pointed over this way and it was discharged. My hand was not on the trigger, it was on the barrel... he wouldn't let it go, it discharged. It went through the left hand rear view (mirror) and killed Ms Clay dead.'

Lynn claimed he hid the shotgun upon Mr Hill letting go of it only to be confronted by him again moments later armed with a kitchen knife.

'He advances towards me with a knife in his right hand and a fist clenched in his left. He first takes a swing with his left hand, I blocked it,' Lynn said.

'With his right hand, he takes a swing with the knife, I (grabbed) his wrist and with my left arm pulled over his right and he pushed me over back on the ground and the knife went into his chest.

'He rolled over and when I got off him he crawled a little bit then he stopped moving. And I thought, "What am I going to do?".'

Lynn claimed he checked for signs of life on both the campers but quickly realised they were both dead.

'And from here I panicked. You know that's my shotgun, one person dead, he's dead as well now. And I'm going to be found guilty of this,' Lynn said.

The jury heard Lynn quickly worked to cover up the bloody crime. 

The trial is expected to continue into next week before the jury is finally asked to retire and consider its verdict.