The Lockerbie prosecutor, Colin Boyd QC, exposed the weakness of his position before even his first witness was called to give evidence last week. Boyd told the world he was not yet ready to start the trial of the two Libyans accused of blowing up flight 103 and he wanted it postponed for eight weeks. It was all the fault of the defence, he said, they had handed over their lists of witnesses and documentary evidence at the last possible moment, just 10 days or so before the trial.

Why would that matter? The answer is to be found in a practice called precognition, one of the mysteries of Scottish law. Prosecution lawyers are allowed to send in police to interview defence witnesses before the trial. Defence lawyers are allowed to send heavy-looking men to interview prosecution witnesses before they come to court. In England, this would be contempt. In Scotland, it may be the only way one side can find out what the other is going to say.

Boyd and his team said that they needed more time to interview 124 new witnesses, most of them in Libya. Scottish law says it can be done in 10 days. And who insisted that this trial would be conducted “according to the law and procedure of Scotland”, with the sole exception that three judges would replace a jury? The Lord Advocate, Lord Hardie. And who was now saying that 10 days notice was not enough? The new Lord Advocate, Boyd.

Colin Boyd made his application for a postponement with “profound regret”. And he certainly had witnesses lined up for the start of the trial if his application failed. But as well as hedging his bets, the Lord Advocate had shot himself in the foot. Weren’t there procedural rules that would allow him to introduce evidence later, either because it was not available before the trial had started or because a defence witness had changed their story? Well, Boyd told the judge, that was not a complete answer to his difficulties – there were all sorts of reasons why the court might decide to exclude such evidence.

Boyd looked far from comfortable. He knew the presiding judge, Lord Sutherland, had told both sides to be ready by May. But the Lord Advocate seemed to lack the forensic skills he would need if the judge was to be persuaded to change his mind. The Lord Advocate’s main opponent proved to be a much more powerful advocate. William Taylor QC, for the first accused, fearlessly reprimanded the judge for saying he would look sympathetically at any application by the prosecution to introduce new evidence. And Taylor pointed out that many of his witnesses should have been well-known to the prosecution anyway – they had been named in police reports that the Crown had received 10 years earlier. The main reason Taylor had not been able to provide his evidence earlier was that the prosecution had not kept to its timetable. And there was plenty of time to interview the Libyan witnesses – as far as the defence could see, their evidence would have no relevance until the court reached Chapter 10 of the prosecution’s case (whatever that might be).

That turned out to be the killer blow. The judge said there was no need to postpone the case. His decision should have come as no surprise to the hapless Lord Advocate. Why then did he take the risk?

Joshua Rozenberg is the BBC’s legal affairs correspondent. He can be contacted at