Twenty years after The Sunday Times first revealed that Thomas “Slab” Murphy was the main fundraiser of the Provisional IRA, the police forces on both sides of the border have finally moved to put him out of business.

In the intervening years, Murphy has made tens of millions of euros from his criminal activities, money that was used to bankroll the Provisional IRA’s campaign of terror in Northern Ireland, Britain and Europe, and no doubt filtered into Sinn Fein’s political campaigns too.

Murphy’s criminality, and his links to terror, have made him one of the wealthiest gangsters in these islands. If the combined efforts of the republic’s Criminal Assets Bureau and Northern Ireland’s Assets Recovery Agency can shut him down and claw back the proceeds of his crime, they will have struck a significant blow for democracy and normality in Northern Ireland.

Murphy is one of the most senior and most sinister members of the republican leadership. He believed himself to be untouchable, and years of inactivity by the security forces will only have reinforced that belief.

When he was named as an IRA leader by The Sunday Times in the mid-1980s, Murphy’s reaction was to deny the charge and to sue for libel in Ireland, supremely confident that nobody would dare testify against him. In this he was mistaken. Brave and honest men — such as Eamon Collins, Sean O’Callaghan, Brendan McGahon, a former Fine Gael TD, and Dan Prenty, a former garda detective inspector — got into the witness box on behalf of this newspaper and Murphy was proved wrong. He lost his case, and his reputation. Collins later paid with his life for his willingness to testify against Murphy; he was beaten to death by members of the Provisional IRA.

Gerry Adams, the president of Sinn Fein, who denies that he was ever a member of the IRA, says that Murphy is not a criminal but a “good republican” who is “a keen supporter of the Sinn Fein peace strategy”.

As always, his choice of words is careful, but contains both menace and mendacity. Adams’s warning to the authorities is implicit: mess with Murphy and you endanger peace. And in Adams’s perverted sense of morality, there is no such thing as a criminal republican. Just as he believes that the men who shot down garda Jerry McCabe were not criminals, so he believes that Murphy the smuggler is a good republican and upstanding citizen.

The police and the Irish and British governments must pay no heed to his words. Murphy has played a central role in the subversion of Irish democracy, north and south of the border. It was an affront to society that he remained unchallenged and open for business eight years after the signing of the Good Friday agreement. The governments have tolerated the republican movement’s slow transition from terrorism to democracy long enough.

Adams claims to support the recovery of criminal assets and says that criminals should face the full rigours of the law. Yet he cannot bring himself or his party to co-operate with or endorse the Police Service of Northern Ireland. His support for Murphy may be deemed essential within republican circles, but it makes a mockery of his pretensions to be a democrat. It is imperative, though, that the CAB and ARA maintain their pressure on all the criminals who have profited from years of terror.

A show of strength on a border farm plays well in the media for a day, but the real proof must come from the recovery of assets and from the prosecution of those involved.

The move to shut down “Slab” Murphy has been too long coming, and the delays have cost lives. This must not be a false dawn.

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