So, it seems Gaddafi is, at last, vanquished.

President Barack Obama has reportedly asked Libya’s rebel leaders to capture the terminally ill 59 year-old so he can be sent to face justice in the US. This would be as illegal as it would be inhumane -- not that legality has been a pre-condition of recent US foreign policy.

It’s far more likely that he will become the victim of disinformation.

It will not be the first time. On February 22, 2011, I posed the following rhetorical question on Professor Robert Black’s Lockerbie blog: “What’s the betting that, sometime in the next few weeks, the following happens: 1) In the burned-out ruins of a Libyan Government building, someone finds definitive documentary ‘proof’ that Libya and Megrahi were responsible for Lockerbie and/or 2) A Libyan official reveals ‘we did it’.”

I pointed out that the case against Megrahi was now so thin that only such concoctions could save it.

Within 24 hours the country’s newly defected Justice Minister, and now leader of the National Transitional Council, Mustafa Abdel Jalil, told a Swedish newspaper: “I have proof that Gaddafi gave the order on Lockerbie.”

Gaddafi may be an appalling tyrant, but there is no more reliable evidence that he was behind the Lockerbie attack than there was that Saddam Hussein was behind 9/11.

Mr Jalil knew the claim would help distance him from his old boss and win him friends in Washington and Whitehall .

His knowledge that the prosecution case was beyond repair probably accounts for why he later told a newspaper that Megrahi “was not the man who carried out the planning and execution of the bombing”, but was “nevertheless involved in facilitating things for those who did”.

Any credibility that this gained him was, however, destroyed by his claim that Megrahi had blackmailed Gaddafi into securing his release from prison by threatening to expose the dictator’s role in the bombing, and had “vowed to exact revenge’” unless his demand was met.

The notion that Megrahi held any power over Gaddafi was ludicrous: he was reliant on Gaddafi’s Government to fund his appeal and to shelter his family in Tripoli, so would have been insane to attempt blackmail.

Other senior defectors’ “Gaddafi did it” claims are equally dubious.

One of them, Abdel Fattah Younes, was so distrusted by some of the rebels that they killed him, while another, the ex-ambassador to the UN, Abdul Rahman al Shalgham, has previously denied Libya’s guilt.

So too has the mysterious Moussa Koussa, Gaddafi’s supposed terrorist godfather, who was reported to have helped the Scottish police with their inquiries.

If the official account of Lockerbie is true, this was like Radovan Karadzic helping the Srebrenica massacre investigation.

But it’s almost certainly not true, which is probably why Mr Koussa remains free.

And it’s why we should expect more dodgy evidence to emerge from newly liberated Tripoli, in particular, stories that patch over the gaping holes in the prosecution case.

I once said to Megrahi that I expected to read that he had made a deathbed confession. I was joking, but I’m not now.

  • John Ashton is the author of Megrahi: You are my Jury, which will be published later this year.