Having finally admitted murder, jailed Prout led detectives to the spot where he concealed Kate, 55, in woods on the 276-acre estate after strangling her during a row over a divorce settlement.
Police search woodland on Redhill Farm in RedmarleyThe balding businessman made the admission taking a lie detector test – which he then failed.
British and European Polygraph Association chairman Don Cargill, recalled: “I said, ‘You’re a murderer.’ He just said ‘Ummmh.’ So I said, ‘Are you saying my test is wrong?’
“He actually replied, ‘No, your test is not wrong.’”
Don, also said: “He smiled in what was one of the most surreal and chilling experiences of my life.
“There was no emotion at all, he was really calm and cool, chillingly so.
“He’d been so used to being in control. He didn’t fool the jury but he’s fooled a lot of other people, his family and friends and his fiancee.
“I can understand why people fell for his lies – but of course, you can’t fool a polygraph.”
Debbie Garlick, who allegedly began dating Prout a year after he murdered Kate, had even launched a campaign to win his freedom.
He was jailed for life in February 2010 despite his wife’s corpse not being found.
Debbie offered a £10,000 reward for any information proving him innocent.
Heartbroken Debbie told of the moment he finally admitted he had been lying to her all along.
She said: “He just confessed. He said: ‘I’m sorry, I did.’ Myself and my family are obviously devastated.
“My heart goes out to Kate and her family. I hope this gives them the chance to grieve properly for their sister and have a proper burial and somewhere where they can lay flowers.”
After the confession, Debbie warned Prout she intended to tell police immediately that he had admitted the murder. Unknown to Debbie two police detectives had already been to visit him at Garth Prison where he had admitted to them of murdering his estranged wife Kate.
Friends said the devastated mum-of-three had changed her Facebook status to single.
One pal said: “Debbie’s in turmoil. She’s been extremely loyal to Prout.
“I think Prout finally decided the game was up and he had to confess when people close to him started losing faith after he failed the lie test.”
Prout was taken from Garth prison, Preston to his former marital home, Redhill Farm in Redmarley, Glos, handcuffed to a detective.
The home of Kate Prout and Adrian ProutHe was then driven up a dirt track beside the farmhouse in a police car and across a ploughed field to woods.
Less than half an hour later, he was driven back across the same field before being returned to Prison.
Kate’s grieving family had pleaded with Prout to end their misery and tell police where he had hidden her body after a judge jailed him for a minimum of 18 years.
But he insisted Kate had walked out leaving her handbag, phone, passport and purse, which were found at the farm.
Debbie and 21-month-old Evie moved out two weeks ago to a smaller home in nearby Kempley.
Hairdresser Beccy Webb, 47, who lives less than half a mile from the farm, said “I cannot believe she lived here in the village.
“A lot of people around here thought he did it.
“It is no surprise to me because I knew he had done it. But there will be people here who are really shocked.
“People trusted him – including his partner Debbie. She must be devastated to believe somebody for that long then to find out it was a lie.”
Parish councillor Mike Phillips, 76, who also lives in the village, added: “Everyone was shocked to learn that, having said for so long he had never done it, he had confessed.”
Divorced Prout originally bought the farm with teacher wife Kate for £820,000 in 2004 – four years after he and the farmer’s daughter wed.
He ran a successful pipe-laying firm and pheasant shoot at the farm and Kate had her own blueberry plantation.
But their marriage began to fall apart in 2006 and violent Prout was desperate to divorce Kate on terms which would allow him to remain at the farm.
It is thought he has admitted he strangled Kate in a shooting lodge at the farm on Bonfire Night 2007 after she demanded an £800,000 clean-break divorce he could not afford without selling the estate.
Kate’s brother Richard Wakefield said in a family statement: “We have always wanted Adrian to tell us where Kate’s body is. However, this news has obviously come as something of a shock to us. We would like to be given some time to come to terms with this news.”
Det Supt Simon Atkinson commented: “A detailed search of the location will be conducted next week. However, this will be a painstaking process so is likely to take some time.”