ALLEGATIONS that police plotted to mislead the original inquiry into the Lockerbie bombing, resulting in a wrongful conviction, have been passed to official investigators, it is understood.

The file being considered by the Scottish Criminal Cases Review Commission claims evidence gathered at the scene of the 1988 bombing of Pan Am flight 103, which killed 270 people, was lost or destroyed.

Misleading or false evidence, it is alleged, was then provided to incriminate Abdelbaset Ali Mohmed al-Megrahi, the Libyan agent convicted of the atrocity at a trial in the Netherlands in 2001.

According to the file, the police investigation of Megrahi was “reverse-engineered” with evidence provided to match the thesis that he was guilty.

The commission is preparing on Thursday to report the results of its three-year investigation into the case. Its 800-page report is expected to conclude Megrahi’s conviction is unsafe.

If, as expected, his case is referred back to the appeal court, his legal team plans to lodge an application for him to be freed while the court decides whether to quash his conviction or to order a retrial.

The development could bring embarrassment for the government, coming the day after Tony Blair’s departure from Downing Street. The surrender of suspects by Muammar Gadaffi, the leader of Libya, was a key element in Blair’s dealings with Tripoli.

This led in 1999 to the reestablishment of diplomatic relations with Libya after a 15-year hiatus.

Details published today from hundreds of leaked documents outline some background to the commission’s decision. Its report is expected to consider allegations that clothing said to have been wrapped around the bomb and presented to the court in tatters was intact when found.

The defence argues apparently damning pages in the case against Megrahi were inserted into existing files. They also claim key statements were withheld. These included at least two by Tony Gauci, a Maltese shopkeeper who sold a shirt to the bomber.

Statements by Gauci published in part in Scotland on Sunday, show him giving different versions of events from his later identification of Megrahi. In one, he “very positively” identifies to a detective the man in his shop as Mohammed Abu Talb, a terrorist with links to the Iranian-backed Popular Front for the Liberation of Palestine – General Command (PFLP-GC).

In a separate statement, Gauci tells police Megrahi “didn’t buy any shirts for sure” from him.

The commission is also in possession of a press statement, prepared by Dumfries and Galloway police in 1990, which named members of the PFLP-GC as its chief suspects but which was never released.

The commission is also understood to have investigated allegations that a police officer showed Gauci a photograph of Megrahi in a magazine shortly before he was asked to identify the Libyan at his trial.

The shopkeeper’s eventual identification of Megrahi in court was regarded as pivotal in persuading the judges of his guilt.

“There’s no doubt Megrahi was convicted because of Gauci’s identification,” said a source. “If Gauci was shown a single photograph of Megrahi shortly before he went in to give his evidence, that would be explosive.”

The quality of evidence concerning a fragment of circuit board allegedly found at the crash site – which was instrumental in convicting Megrahi – has also been questioned.

Other evidence has been given to the commission by a former senior officer in the Lockerbie inquiry, known only as “the Golfer”. He is understood to claim evidence was “interfered with”.

Megrahi’s trial was the longest and most expensive in Scottish legal history. A second defendant was acquitted. An appeal in 2002 upheld the original verdict.

It lends further weight to claims that it was “politically unacceptable” to pursue the PFLP-GC when the Gulf war in 1991 made it necessary to maintain good relations with Iran and Syria.

Robert Black, emeritus professor of Scots law at Edinburgh University, who helped broker Megrahi’s trial in the Netherlands, said: “My concerns have always been about what actually happened and getting to the truth. [Megrahi] should not have been convicted on the evidence before the trial judges.”

Dr Jim Swire, whose daughter Flora died in the bombing, said: “If the Crown Office [public prosecutors] deliberately withheld relevant material it would be a very significant development.”

Tony Kelly, who is Megrahi’s solicitor, and Dumfries and Galloway police and the Crown Office all declined to comment.

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