Thirty years on from the Lockerbie bombing, the case of the only man found guilty over the atrocity could still return to court.

To this day, the conviction of former Libyan intelligence officer Abdelbaset al-Megrahi remains highly controversial, with some bereaved families believing it was the right verdict and others arguing it was one of Britain's worst miscarriages of justice.

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Now a comprehensive review of the case is being carried out by the Scottish Criminal Cases Review Commission (SCCRC) to determine whether or not a fresh appeal against the conviction should proceed.

The review comes after Megrahi's family pushed forward a bid for a posthumous appeal, handing files to the SCCRC in 2017.

Announcing in May that it would look fully at the case once more, the commission - which has the power to refer cases back before senior judges - said it believed Megrahi had abandoned a previous appeal because he had "a genuine and reasonable belief" that doing so would help him return home to Libya when he was suffering from terminal cancer.

The review prompted the ex-MSP who controversially freed Megrahi to warn that the case against him could still collapse.

Former Scottish justice secretary Kenny MacAskill said the evidence of the late Maltese shop-keeper Tony Gauci, which was critical in the case against Megrahi, was one of the issues expected to be looked at.

The bombing of Pan Am flight 103, travelling from London to New York four days before Christmas, killed all 259 people on board.

Eleven residents of the Dumfries and Galloway town also died after the plane crashed down on their homes in Britain's biggest terrorist atrocity.

After protracted international pressure, Megrahi was put on trial at a special Scottish court sitting at Camp Zeist in the Netherlands.

He was found guilty in 2001 of mass murder and jailed for life with a minimum term of 27 years.

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Al Amin Khalifa Fhimah stood trial with Megrahi, but was acquitted.
Megrahi remains the only man ever brought to justice over the terrorist attack, despite claims that he could not have worked alone.

In 2015, Scottish prosecutors identified two Libyans as suspects in the ongoing investigation into the bombing, although violence in Libya since the fall of Gaddafi is thought to have made progress in this area difficult.

Megrahi lost an initial appeal against his conviction in 2002, but by 2007 the SCCRC recommended that he should be granted a second appeal.

A £1.1 million investigation by the body led to a finding of six grounds where it believed a miscarriage of justice may have occurred.

The court process was ongoing when, suffering from terminal prostate cancer, Megrahi dropped the second bid to overturn his conviction in 2009, ahead of his return to Libya.

In 2012, he died protesting his innocence at the age of 60, three years after being released on compassionate grounds.

The 2009 decision by Mr MacAskill to free Megrahi from Greenock prison and allow him to return home to die drew international condemnation at the time.

While Scottish ministers have always insisted the move was made in good faith, US families, the then US president Barack Obama and the then US secretary of state Hillary Clinton were among those to criticise the decision.

American fury was compounded by the hero's welcome Megrahi received in Tripoli upon his return.

Getting the SCCRC to look afresh at the conviction following Megrahi's death has been a complex process.

His family submitted files to the SCCRC in Glasgow in July 2017 and the application for a full review was accepted in May this year.

Earlier, in 2015, the body had decided "with some regret" to halt a review after receiving an application from some campaigners, said to be supported by the Megrahi family. It cited frustrations over a lack of access to certain paperwork.

That approach to the SCCRC - said to involve 24 British relatives of those who died in the atrocity and six immediate members of Megrahi's family - was believed to be the first time in UK legal history that relatives of murdered victims had united with the relatives of a convicted deceased in such a way.

Meanwhile, a long-running petition from the Justice for Megrahi campaign group, calling for an independent inquiry into Megrahi's conviction, remains open at the Scottish Parliament, with MSPs on Holyrood's Justice Committee keeping an eye on developments with the application before the SCCRC.

Last month it was confirmed that a police investigation, dubbed Operation Sandwood, has found no evidence of criminality in relation to the handling of the investigation and prosecution of the Lockerbie bombing case.