The commission investigating whether there was a miscarriage of justice at the Lockerbie trial has criticised the former Lord Advocate who led the landmark prosecution.

Colin Boyd, QC, now Lord Boyd, was head of the team which has been accused of failing to disclose crucial information to the defence working on behalf of Abdelbaset Ali Mohmed al Megrahi, who was convicted of the bombing of Pan Am Flight 103.

In its 821-page report, the Scottish Criminal Cases Review Commission (SCCRC) criticises Lord Boyd for his handling of CIA cables, referring to Abdul Majid Giaka, an alleged double agent who was a Crown witness. Giaka identified Megrahi as a member of Libyan intelligence, but his subsequent evidence was rejected following revelations in the US intelligence agency's much-redacted cables that he had demanded and received reward money.

Lord Boyd originally told the trial there was no need for disclosure.

However, the SCCRC said it was "difficult to understand" his assurances on August 22, 2000, that there was "nothing" within the documents relating to Lockerbie or the bombing which could "in any way impinge" on Giaka's credibility. It added: "The matter is all the more serious given that part of the reason for viewing the cables on 1 June, 2000, was precisely in order to assess whether information behind the redacted sections reflected upon Majid's credibility."

The Crown subsequently shared some of the redacted cables after demands from the defence.

Lord Boyd last night rejected the commission's claim. He said: "I reject the suggestion that I or anyone else in the prosecution team failed to disclose material evidence to the defence. All of the relevant CIA cables were disclosed subject to some exceptions, principally to ensure that the lives of named individuals were not put at risk. They were disclosed as a result of a request from the court directed to me.

"I am satisfied that the Crown acted with propriety throughout the trial and endeavoured in this case, as with any other conducted in my name as Lord Advocate, to secure the accused's right to a fair trial." He added he was "satisfied" the verdict was proper and correct.

The SCCRC report refers to a number of occasions when it was not granted full access to security documents from the CIA. It was not allowed to disclose certain documents about the case – including one relating to timers found in Senegal which were similar to those thought to have caused the tragedy, and claims by former CIA staff.

The UK Security Services complied with all requests to share information with the SCCRC but said a number of documents could not be disclosed because of national security.

Yesterday, The Herald reported that the SCCRC dossier uncovers serious discrepancies in the Crown Office's reasons for not disclosing vital information. The commission, which reviews cases post-appeal and investigates possible miscarriages of justice, told the Crown it would take legal action if the prosecution did not hand over important documents and speed up information sharing.

Legal experts have now called for a

public inquiry into who was responsible for the 1988 atrocity, full disclosure of the SCCRC report and an inquiry into Crown Office practice not to disclose key evidence to the defence during the trial.

Last night Justice Secretary Kenny MacAskill wrote again to his UK Government counterpart, Kenneth Clarke, to ask for an exemption under data protection laws to allow the document to be published.

A Scottish Government spokeswoman said: "With virtually every passing day, more and more of the content of the SCCRC's Statement of Reasons in the Megrahi case comes into the public domain. Ministers firmly believe this selective reporting of the information only emphasises the importance of the SCCRC being able to decide to disclose information in the Megrahi case."

A spokesman for the Crown Office said: "This highly selective reporting of the commission's consideration of the CIA cables and Majid gives a misleading account of this evidence and the role of Lord Boyd.

"In particular, it fails to acknowledge that the commission concluded that there was no miscarriage of justice on this point and it also ignores the trial court's thanks to Lord Boyd for his efforts to bring this complex and sensitive information before the court.