Matt Berkely, whose brother died on Pan Am 103 in 1988 has questioned the accuracy of evidence Kenny MacAskill gave to MSPs in Parliament and to the Justice Committee.

Berkley says evidence about the prison visit and the terms of the Prisoner Transfer Agreement question the propriety of Mr MacAskill's choice to delay the transfer decision until Megrahi abandoned his appeal.

He also asks how the Lord Advocate failed to give correct legal advice.

"Contrary to Mr MacAskill's statements, there appears to be no evidence supporting a claim by Mr MacAskill to two parliamentary inquiries that Jack Straw committed Mr MacAskill to taking representations from this prisoner on transfer,” Berkely told The Firm.

“A question arises as to whether Mr MacAskill followed due process in what he described as a 'quasi-judicial' decision. The problem may bolster concerns that Mr MacAskill was negligent in failing to deal with the decision promptly. He might reasonably have been expected to take care to avoid tempting a prisoner to abandon his appeal, especially when the prisoner was in such obviously political circumstances."

MacAskill told the Justice Committee on 1 December 2009 that :"Jack Straw made it clear that, because this was the first situation in which a Government made an application, the prisoner should be given the opportunity to make representations."

Those statements, says Mr Berkley, appears to have no support, and that Mr Straw did not make those claims.

"What Mr Straw committed the UK to does not appear to be what Mr MacAskill followed,” Berkely said.

“Mr MacAskill made an invitation to the prisoner without advising him of an intention to transfer. Mr MacAskill never reached the stage of having any such intention, let alone telling the prisoner. More importantly, perhaps, the context of Mr Straw's commitment appears to be about something else: human rights of prisoners about to be transferred against their will, not those who had already said they wanted to go.

"Mr MacAskill repeated similar claims to the Scottish Parliament Justice Committee and Westminster Scottish Affairs Committee."

Mr MacAskill has been asked to repond to Berkely's claims.