Four men were cleared of snatching Aaron Hunter – then a 16-year old student – from his home in Clermiston in 2008.
He took to the witness stand during the trial at the High Court in Glasgow last month, but refused to give evidence against the accused.
Judge Lord Stewart ordered an inquiry, threatening to find Hunter in contempt of court, which carries a maximum prison sentence of two years. But at the High Court in Edinburgh yesterday, the judge said he suspected that Hunter was pretending he had lost his memory because he was afraid of reprisals.
Defence advocate Mark Moir told the court that a psychologist and a psychiatrist had examined Hunter and agreed he could have been pretending, or genuinely suffering from psychogenic amnesia, brought on by the trauma of his ordeal.
The judge told Hunter: “No court properly directed could come to the view, beyond reasonable doubt, that you were faking amnesia and had intentionally and deliberately refused to give evidence.”
The four men had been accused of helping Glasgow gangster Kevin “Gerbil” Carroll, who was gunned down in 2010, kidnap the teenager.
Joseph Lindsay, 27, and Brian Sloan, 22, were acquitted by a jury and the case against them was found not proven.
Two co-accused, Craig Gallagher, 32, from Glasgow, and Sean Givens, 27, from Liverpool, were acquitted of the abduction and attempted extortion charge during the course of the 28-day trial.
They were accused of seizing the student, forcing him into a car, punching him and threatening to stab him.
The trial heard that Hunter had given detectives a 24-page witness statement hours after he was released by his captors.
Detective Sergeant Carol Craig, from Lothian and Borders Police, took the statement from the teenager at Kirkby police station in Liverpool.
When asked about the youth’s demeanour, DS Craig told the court: “He was very composed but he was tired and anxious to get home.” Asked if he was “hesitant” or “evasive”, DS Craig replied: “No.”
The statement included a detailed account of Hunter’s ordeal on October 24 and 25, 2008. He told officers that gangsters bundled him into a car and kept him overnight in a house after beating him.
They threatened to do “bad stuff” to his family if he spoke to police before releasing him on an empty road in England.
It was the third time that all four men were on trial for this offence. The legal bill was put at £400,000 by court insiders.
The kidnappers threatened to kill the teen if their demands were not met, but they released him at 5pm on October 25.