MSPs have decided that a petition calling for an inquiry into the conviction of Abdelbaset al-Megrahi for the Lockerbie bombing will remain open.

It is difficult to tell whether it is a development of any major significance. Is it simply a minor piece of bureaucracy being allowed to limp through Parliament before it fizzles out or can it really help pave the way for a genuine review of the case to take place?

Members of the Scottish Parliament’s Justice Committee voted six to three last week to allow the petition to come back to them at a later date.

Megrahi, who has prostate cancer and was released from Greenock Prison on compassionate grounds in 2009, is the only person ever convicted of bombing the US-bound flight over Lockerbie in 1988.

The petition was brought by the Justice for Megrahi group, which includes the father of one of the victims.

Dr Jim Swire, whose daughter died on flight Pan Am 103, insists Megrahi is innocent of the crime.

The petition said: “It is time for the government of Scotland to show real independence by standing up to the UK and US governments and other vested interests and instituting an open and accountable judicial inquiry that would at last free the people of Scotland and the relatives of those lost in that terrible tragedy 22 years ago.” Committee convener, MSP Christine Grahame (SNP), said the petition should be kept open “until all the parts of the legislative jigsaw come together”.

She added that there was unfinished business in relation to Lockerbie events, including the unpublished conclusions of the Scottish Criminal Cases Review Commission, which said Megrahi may have been a miscarriage of justice victim.

Four years ago, the SCCRC published an investigation into Megrahi’s initial trial and appeal.

It listed several points which could challenge the original conviction.

A ruling has meant that the SSCRC statement of reasons cannot be made public unless everybody concerned, for instance, the Foreign and Commonwealth Office, consent.

In the run-up to May’s Scottish Parliament elections, the SNP insisted it would produce a bill to ensure publication of the SCCRC report.

This has still to occur – but when it does, many will ask why the Government did not push to have this done earlier.

It is the biggest criminal trial in Scottish legal history and it has worldwide implications.

The number of people who seem convinced beyond a reasonable doubt of Megrahi’s guilt seem to be falling into a small minority.

Later this week, Lord Carloway will publish a year-long review into the Scottish criminal justice system – an exercise that the Scottish Government insists will ensure the country can continue to boast a legal system that is underpinned by fairness and decency.

It becomes increasingly difficult to tell what reputation the Scottish legal system will continue to enjoy while so many questions central to the country’s most important criminal case remain unanswered.