Abdelbaset al-Megrahi is a household name in Britain and the US these days – even if he wasn't before being released from his Scottish jail on compassionate grounds amidst international controversy last summer. But is the only man convicted of the Lockerbie bombing about to be joined by another – as yet anonymous – Libyan suspected of murdering policewoman Yvonne Fletcher 26 years ago?
It is a story that refuses to go away. In a new ITV film about Fletcher's killing outside the Libyan People's Bureau in London's St James Square in 1984, Oliver Miles, then Britain's ambassador in Tripoli, has revealed how the UK government was warned not to allow a demonstration by opponents of the regime to go ahead. It was ignored. The diplomats inside, presumably including whoever fired the fatal shots, were allowed to leave the country after a tense 10-day siege. Others were deported to Libya.
Progress has been made in recent years. Libya admitted "general responsibility" for Fletcher's death in 1999 and paid £250,000 in compensation to her family, paving the way for diplomatic relations with the UK to be restored – an early stage of Muammar Gaddafi's return from the cold. It transpired later that it had also been quietly agreed that if any Libyan was ever charged, they would stand trial in Libya, not in Britain. (Megrahi and the only other Lockerbie suspect, who was acquitted, were tried at a special Scottish court in the Hague).
Optimism has grown in the last few weeks after Scotland Yard detectives were allowed to return to Libya to pursue their inquiries for the first time in three years. Daniel Kawczynski, a Conservative MP, has now dropped his plan to use parliamentary privilege to name the suspect in order, he says, not to hamper the investigation.
Possible suspects were identified in the Guardian long ago, though there were unconfirmed rumours that some of them were executed in Libya. In 2007 a draft report by the Crown Prosecution Service named Abdel-Qader Baghdadi and Mohammed Maatouq, members of a Libyan revolutionary committee, as possible conspirators to murder. It is unclear whether one of them could be accused of the actual shooting, but it is certain that both are now senior figures in Tripoli. "It is inconceivable for Gaddafi to give them up," one Libyan exile told ITV.
To anyone who has followed the twists and turns of the Lockerbie saga – this is a familiar pattern: of flat denials, stonewalling, promises of cooperation, limited cooperation – followed by a special deal (like the early release of the terminally ill Megrahi) that reveals hard-headed realpolitik on both sides.
The late Robin Cook, who oversaw the 1999 rapprochement when he was foreign secretary, put it well: "The aim of our foreign policy must be to strengthen our security by deepening our alliances and promote our prosperity by widening our commercial links. That means that sometimes we must be willing to build a working relationship with governments even if they do not share all our values."
Relations between Britain and Libya are flourishing these days: thus the wish in London and Tripoli to put past embarrassments behind them – and the anguish when, as the anniversary of Megrahi's release approached last month, more damaging publicity is generated. US politicians are still asking difficult questions about whether the whole episode was designed to help BP or other UK businesses secure lucrative contracts.
Neither side wants to see controversy re-ignited over the Fletcher affair. "We can't leave it to cosy talks between British and Libyan officials," warns Kawczynski. But that has been the story so far.
• This article was amended on 6 September 2010. The original credited the recent TV documentary about the killing of Yvonne Fletcher to ITN. This has been corrected.
