WITH TERRORISM in our midst again, not many people have the stomach to disinter an attack that goes back 17 years. The case of Pan Am Flight 103, destroyed by a bomb over Lockerbie on December 21, 1988, killing 270 passengers and crew, is now history.

A Libyan was found to be responsible, and, after a lengthy judicial process and a meticulous trial, Abdul Baset Ali al-Megrahi was convicted and is serving a life sentence in Glasgow for the crime. His co-accused, another Libyan, was cleared. The investigation has been closed.

I have always felt uneasy about the convenience of it all. In the months after the attack, all the evidence pointed in a different direction — to the involvement of Syria, and a terrorist group known as the Popular Front for Liberation of Palestine General Command.

Alan Hutchison, who was then the chief reporter for The Scotsman and a dogged investigative journalist, began picking up information that led back to a group that had trained in Germany, and whose links were with Damascus. At the time I was Editor of the paper, and the stories we ran through most of 1989 were not only increasingly detailed, but were confirmed, albeit indirectly, by the authorities in Washington and the Crown Office in Edinburgh. Sources close to the Lord Advocate, Lord Fraser of Carmyllie, indicated that we were on the right trail.

All that changed, some time in 1990, when we were told about the discovery of forensic evidence that suggested a Libyan link. Fingertip searches of the huge area where scattered pieces of the wreckage had come down had uncovered burnt fragments of a Toshiba radio-cassette player hidden inside a Samsonite suitcase.

From the clothing in which the cassette player had been wrapped, detectives were able to trace it back to Malta, and there close questioning of the shop owner where the clothes had been bought implicated two agents of the Libyan intelligence service. It was, said Lord Fraser at the time, old-fashioned detective work of the highest order — and it was enough to secure al-Megrahi’s conviction in 2001. The complications of a Middle East link were shelved, There the matter might well have rested, save for a series of allegations that have emerged over the past year, and which suggest that this apparently watertight evidence may be not only flawed, but might possibly have been tampered with.

A senior Scottish police officer, now retired, claims that American intelligence agents planted one of the fragments of the cassette-player in order to implicate the Libyans. Doubts have been cast on the reliability of an expert forensic scientist who gave evidence about the detonating of the bomb — three other convictions in which he gave testimony have been quashed. And it now seems that tests on the suitcase may have been misrepresented to the court.

All this might easily be dismissed as the conspiracy fog that tends to gather around cases of this kind. Except that last weekend Lord Fraser himself, who was in charge of the Crown evidence, suggested that he too had begun to have doubts. In an interview with The Sunday Times he said that the Maltese shopkeeper, Tony Gauci, whose identification of the two Libyans was central to the prosecution case, might not have been a reliable witness. He was, said Lord Fraser, a “weak point” in the case, who might have been “easily led”. He added: “Gauci was not quite the full shilling. I think even his family would say [that he] was an apple short of a picnic. He was quite a tricky guy . . .”

It is, I think, safe to say that if these opinions had been voiced at the time the prosecution case would have been holed beneath the water line. Gauci’s evidence was critical in linking al-Megrahi to the attack. Without it, al-Megrahi would certainly have walked free. Lord Fraser’s remarks have been described as “an extraordinary development” by Tam Dalyell, who was a key figure throughout the investigation. Senior legal experts in Scotland have expressed amazement at his comments. And William Taylor QC, al-Megrahi’s defence advocate, has called for a review of the case.

Does any of this matter now, so many years after the event? After all, there have been no noticeable protests from the Libyan Government. So long as al-Megrahi is allowed to serve the rest of his sentence in Libya, rather than in Scotland, it is unlikely to want to resurrect a case that could undermine its newly established relationship with the West.

That, however, is not the point. It is the British Government that should be concerned. Our defences against terrorism rest ultimately on trust in our legal system, on the reliability of our police work and on the demonstrable transparency of our judicial process. If these become suspect in one case, then they will be open to doubt in another. Evidence that has been misrepresented in such a high-profile trial may be called in aid by the accused in another, who may use it, however indirectly, to undermine the prosecution case and influence the mind of a jury.

It is a slippery slope that leads ultimately to the erosion of our basic defence against terrorism. However much it goes against the grain, the Pan Am conviction must be re-examined, to determine whether there is strong enough evidence to reopen the case. If necessary, Lord Fraser may need to be questioned by the Scottish criminal review system. It could turn out to be a lengthy, time-consuming and expensive process. But it will be worth it if it serves to uphold the integrity of our legal system.

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