Defense lawyers said Monday new evidence will be disclosed during the appeal.
At a preliminary hearing at a special Scottish court in the Netherlands, presiding judge Lord Cullen gave Megrahi's counsel four weeks to lodge the outlines of the arguments they will use at the appeal. Prosecutors will then have four weeks to respond.
The appeal opened with a preliminary hearing that set the latter half of January for substantive arguments, nearly one year after the conviction of Abdel Basset Ali al-Megrahi for planting the bomb that blew up Pan Am Flight 103 over Lockerbie, Scotland.
Al-Megrahi was sentenced Jan. 31 to life imprisonment for killing 270 people, 179 of them Americans, in the Dec. 21, 1988 explosion. Since then, he has been the only occupant of the lockup on the compound near a former air force base that was converted to a court facility for the trial.
"The date of the hearing is 23rd January of next year for the appeal itself," Lord Cullen said at Megrahi's first court appearance since his sentencing.
The judge said it was highly likely another procedural hearing would be necessary before the appeal began, and any such hearing would be held on January 7.
"A decision as to whether there will be a further procedural hearing will be taken as soon as possible, and certainly by December 17," he told the court, wrapping up an almost three-hour hearing.
Chief defense attorney William Taylor told the court the defense had uncovered statements taken by police officials after the crash and "not presented to prosecutors" or heard in court. He gave no details of new evidence or the statements, referring only a "security officer" who came forward with "real" material.
It also was not clear if Taylor was referring to a former security guard at Heathrow airport who reportedly said last month he discovered a break-in at a Pan Am baggage facility early on the day the New York-bound jetliner was destroyed.
Ray Manly, 63, was quoted in Scottish newspapers as saying he was surprised the incident was not mentioned during the trial.
With al-Megrahi listening through headphones to a simultaneous translation, the five-judge panel rejected an appeal from Marina de Larracoechea, whose sister Maria was a stewardess on board the doomed plane, to personally intervene in the appeal.
"There is evidence that was not presented in the trial that I think was missed," she told the judges, urging an independent review of the investigation. "I only seek the truth and justice of the case as soon as possible, like most of the relatives."
But the court ruled there is no procedure in Scottish law that would allow the victims' families to participate.
The appeal comes at a time when the world is confronted anew with the problem of capturing terrorists and bringing them to justice in response t the Sept. 11 attacks in the United States.
The Lockerbie trial illustrates the difficulties of finding evidence that stands up to judicial scrutiny and of tracking the perpetrators to their source.
Although the 12-year investigation and the course of the 9-month trial implicated Libya in the bombing, no one was ever charged for planning or ordering the attack. Families of the victims have said they will exhaust all legal possibilities to reveal who ordered the attack.
The split verdict last January left many in doubt about what actually happened to Pan Am 103, but the Lockerbie case was nevertheless a legal milestone, made possible by a deal between the United States, Scotland and Libya that brought the two suspects to a neutral country where all sides were satisfied they would get a fair trial.
Scottish law allows for an appeal only where there's been a miscarriage of justice or where new evidence has come to light. The judge will review new material before ruling if it merits further examination.
The Scottish court granted al-Megrahi permission to appeal his conviction early this year, but the appeal itself has remained secret. Experts at the Glasgow law school have said it is unlikely to claim a miscarriage of justice because the defendant has not appointed new counsel, a requirement under that procedure.
If the appeal fails, al-Megrahi will be transferred to Scotland, where he will spend at least 20 years in jail. If it succeeds, it would leave one of the largest international terrorism investigations without a culprit.
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