The legal battle between the News of the World and Scottish MSP Tommy Sheridan has taken a dramatic new twist which could have far-reaching consequences.
The News of the World claimed on Sunday that a 40-minute secret video tape "proved beyond doubt" that the MSP had committed perjury during his sensational five-week defamation case against the paper in July and August.
The jury awarded Sheridan record Scottish libel damages of £200,000 for allegations that he was a swinger and had been unfaithful to his wife Gail.
But in a front-page splash and 10 pages of coverage inside yesterday's News of the World, the tabloid declared: "Cheating Tommy Sheridan is today once and for all exposed as a LIAR, an ADULTERER and a HYPOCRITE."
The paper revealed it is preparing to launch legal action against Sheridan, a fellow MSP and Scottish Socialist Party officials who testified during the court case that the MSP denied being a swinger.
The tabloid claims that on the tape Sheridan admits he visited Cupids swingers' club in Manchester on at least two occasions – accusations denied by Sheridan during the defamation case.
It also says that Sheridan admitted on tape that he told an executive meeting of the Scottish Socialist Party that he had visited Cupids despite denying this at the trial.
The News of the World commented: "The bombshell tape is the most explosive piece of evidence in the history of Scottish defamation trials.
"It could send Sheridan to jail for perjury – and it is crucial to the police investigation into four of Sheridan's colleagues in the SSP who swore blind to judge and jury that he had never confessed his sleazy secrets to the executive meeting.
"If they are found guilty, then party MSP Rosemary Byrne and SSP officials Graeme McIver, Pat Smith and Jock Penman could all be facing a jail sentence in high-profile cases that would cut a huge swathe through Scottish politics."
The News of the World said the secret video was recorded in November 2004 by George McNeilage who was the MSP's best man at his wedding and a friend of 30 years.
The paper said that McNeilage had recorded the conversation with Sheridan on a camcorder hidden beneath tiles when he was decorating a room at his home in Glasgow.
It said that McNeilage didn't release the tape at the time because he was certain that Sheridan would lose the defamation case and the evidence wouldn't be needed.
Sheridan last branded the NoW story a "pack of lies", and told BBC Scotland: "A fictitious tape has been invented, concocted and unleashed on a Scottish public sick to the back teeth of the News of the World's constant lies.
"They will not forgive me for humiliating them. Their vendetta against me, my family and my political beliefs continues. They are trying to break me politically and personally. They will fail on both counts.
"My new party, Solidarity, grows daily while my relationship with my wife, Gail, is unbreakable."
And he accused the paper of being "lying rats" who occupy the "stinking sewer of the journalistic world".
The News of the World, which admits that it paid to obtain the video, is now set to take legal action against Sheridan and four officials of the Scottish Socialist Party.
Declaring that it would hand the video over to police, the tabloid revealed: "Furthermore, we are preparing to launch a legal action against Sheridan and the four officials who testified that he DENIED being a swinger. We will be seeking all legal costs from them."
In a by-lined piece, McNeilage said that he knew that almost every word that Sheridan uttered during the defamation trial at the Court of Session in Edinburgh was a lie, "but all of that, for the sake of giving my kids a quiet time, I could maybe have swallowed.
"But for me, Tommy crossed the point of no return a few days after the case. Instead of taking his cash quietly, he attacked the very people he had dragged into this suicidal libel case.
"‘I'll destroy the scabs who tried to ruin me' screamed the front page of one daily paper. For writing such garbage, Tommy was paid £30,000."
The Scottish Daily Record carried exclusive interviews with Sheridan and his wife in the aftermath of the defamation case.
The News of the World, which claims the tape reveals that that Sheridan "told at least two dozen lies in court in a bid to conceal his secret swinging" yesterday carried three pages on what is claimed to be a verbatim report of parts of a conversation between Sheridan and
McNeilage, and promises that on Sunday there will be "more shocks from the Sheridan tape".
In its story, it states that the videotape had been analysed and assesed by four leading authorities on voice analysis – including American Tom Owen who has worked on the verification of Osama Bin Laden tapes for the CIA – who told it : "Everything points to this tape being a genuine recording of the individual (Tommy Sheridan)."
The News of the World has set up a special telephone number for readers to hear the tape of Sheridan's alleged confession with calls costing 50p per minute, or, alternatively, can be accessed on the paper's website.
The News of the World has already appealed the Court of Session jury decision to award £200,000 damages to Sheridan but it could be up to a year before the appeal is heard.