Fergal Keane : A killing that opens up a festering old wound

'To describe the Finucane murder as "murky" is a colossal understatement. The whole business stinks'

According to the Royal Ulster Constabulary he was "just another law-abiding citizen going about his profession in a professional manner". Anybody who came into contact with Pat Finucane in his years as a Belfast solicitor would have to agree. Tough and determined, he was among the most successful criminal defence lawyers of his time. The problem was that "his time" was the Troubles and the people he was defending were mainly IRA suspects, though his reputation also attracted a number of loyalist clients.

His three brothers were all linked in some way to the Republican movement. One was killed in a car crash while on IRA duty, another was on the run in the Irish republic and a third was the fiancé of Mairead Farrell, an IRA member shot dead by the SAS in Gibraltar. But Pat Finucane himself – as the RUC publicly stated – was not an IRA man. He may have had Republican sympathies, but that was his right and something he shared with tens of thousands of other people. Some of his clients claimed that they had been told by Special Branch detectives that Finucane would come to a sticky end as he was a "Fenian Bastard".

I interviewed him several times when I was based in Belfast. He was a busy man, lean and energetic and very brave. He continued to live on the Antrim Road, in north Belfast, although it was one of the most notorious sectarian flashpoints in the city. The district where he lived was known locally as "murder mile".

Three weeks before he was shot dead on 12 February 1989, Douglas Hogg, a junior Home Office minister, made the following remarks during the committee stage of the Prevention of Terrorism Bill: "I have to state as a fact, but with great regret, that there are in Northern Ireland a number of solicitors who are unduly sympathetic to the cause of the IRA..."

Soon afterwards a man whom I know and respect, Seamus Mallon of the SDLP, denounced Mr Hogg's comments and issued a prescient warning. He warned the Minister that it would be "on his head if an assassin's bullet did what his words had done". Mr Mallon is a constitutional politician to the core and has been on the receiving end of intimidation from both republican and loyalist paramilitaries. The reaction from Ulster's legal establishment was equally angry.

"What Mr Hogg has done is to create an excuse for terrorist organisations to carry out murders – something that was not available to them before," the Law Society declared. Three weeks on and Pat Finucane was dead, shot 14 times as he sat with his family at their Sunday meal.

Now spool forward 12 years to this week and a murder that was hardly noticed amid the crowded news agenda. The scene of the killing was north Belfast, and the victim was a loyalist paramilitary turned police informer, William Stobie.

Stobie's story is intimately connected to that of Pat Finucane. Stobie was a quartermaster with the Ulster Defence Association and a Special Branch informer. Earlier this year, Mr Stobie stood trial for aiding and abetting the murder of Pat Finucane, having allegedly confessed his involvement to a Belfast journalist. But the trial collapsed. Guess why? The journalist, who now works for the Northern Ireland Office, refused to give evidence on the grounds that he'd suffered from bad mental health. It is hard to blame the man, given the attitude of loyalist paramilitaries to journalists they don't like – witness the murder of Martin O'Hagan of the Sunday World after he probed too deeply into the affairs of a few of these gangsters.

Stobie had also claimed to have tipped off his Special Branch handlers that the shooting of a Catholic was imminent, although he did not ever admit to knowing the identity of the target. But there is compelling evidence that the security forces were given information by another informer about the possibility of an attack on Mr Finucane. Brian Nelson was another UDA man who turned informer for the Army's "Force Research Unit" – the sinister-sounding title for the army's intelligence-gathering operation in Ulster. Nelson said the UDA asked him to compile a dossier on Finucane – the first stage in the intelligence-gathering process that would lead to his murder. Nelson said his security-force handlers were made aware of this.

The murder of the main witness in the case, and the one person who might be able to tell who organised the killing – critically whether there was security-force collusion – is very frightening. He had no shortage of enemies, and I doubt we will ever know who organised the murder, although the prime candidate must be the loyalist paramilitaries. Stobie will not be talking, and the manner of his silencing is reminiscent of the worst kind of Mafia assassination.

Regular readers of this column will know precisely my attitude to the IRA – its an attitude that leads republican-minded people to regularly send me venomous letters of denunciation. I have covered police funerals and interviewed many widows, enough to understand the kind of pressures that the RUC faced from an enemy that observed no rules in its war. Nor, like many on the Republican side, do I rush to believe the worst of the RUC. But when I wrote some weeks ago about the need for a process of truth-telling in Ulster, I took care to say that we needed to know the truth about paramilitary death-squad killings as well, and to get to the heart of the allegations about security-force collusion with the killers. We are nowhere near that point. The damage done to the reputation of the force by the ongoing allegations of collusion has been catastrophic.

Still more the sense of a police force that is perpetually defensive, that responds to allegations against it with angry denials, or, as in the case of Omagh, an extraordinary outburst from its chief constable, pledging to commit suicide in public if the claims made in the ombudsman's report were true.

To describe the Finucane murder as "murky" is a colossal understatement. The whole business stinks to high heaven, and 10 years on we are still waiting for the truth. In all of this there is a conspicuously good cop, John Stevens, the Commissioner of the Metropolitan Police. His own investigators have experienced the defensiveness and obstruction of elements in the RUC going back to the 1980s, when they were first drafted into the province. After the murder of Stobie, we are more dependent than every on Mr Stevens's skills and determination.

Like most of you, I simply don't know enough to say conclusively whether there was or was not security-force collusion in the murder of Pat Finucane. However, I do know a festering wound when I see one, and without some accounting for what happened, the cause of creating nationalist confidence in a new police service will be seriously undermined. Pat Finucane lived and died for the law, and in that sense his murder was a highly symbolic act. Getting to the truth of who killed him will be the most important work ever undertaken by Mr Stevens.

The writer is a BBC special correspondent