Thomas 'Slab' Murphy has been in the news again as a result of his court case in Dublin, a case that lasted nine weeks. On December 17, he was found guilty on charges of tax-evasion by a three-judge, non-jury, Special Criminal Court and remanded on bail for sentencing early in the New Year.
The case related to his failure to submit tax returns on his income as a cattle farmer for the years 1996 to 2004.
His court appearance followed on from an investigation by the Criminal Assets Bureau in the Irish Republic and a raid on his farm that uncovered bags stuffed with cash. This amounted to €250,000 and £110,000 and was accompanied by diaries and other documents.
According to Toby Harnden, author of the book Bandit Country, Murphy was involved for a long period with the South Armagh Brigade of the Provisional IRA before becoming chief of staff of the IRA around 1979.
He also stated that Murphy was involved in planning a number of IRA atrocities, including the massacre of 18 soldiers at Warrenpoint in 1979 and another bomb on the same day that killed four people.
Of course, 'Slab' Murphy has always denied being a member of the IRA, and he even sued the Sunday Times for libel when it alleged that he had directed an IRA bombing campaign in Britain.
However, he lost the case and, when it went to retrial, he lost again. The jury accepted that he was an IRA commander and a smuggler.
Among those who testified against him were members of the Gardai and former members of the IRA. One of those former members was Eamon Collins, who was murdered on January 27, 1999, just eight months after the court case.
Collins was beaten to death in Newry and a spike was driven through his face. Afterwards, Gerry Adams described the death as "regrettable" but said that Collins had many enemies.
'Slab' Murphy was then arrested on November 7, 2007, in Dundalk and the following day he was charged with tax evasion. Subsequently, in an agreed legal settlement, Murphy and his brothers paid more than £1m to the authorities in the UK and the Republic in settlement of the proceeds of crime, including smuggling and money-laundering.
Then, in March 2013, in a cross-border operation, the Gardai and the PSNI, along with the Irish Customs Agency and HMRC, raided Murphy's farm.
It was reported at the time that shortly before the raid, at 4am, a fire was seen to have been lit on the farm, and it was suggested that Murphy had been tipped off and was destroying evidence.
Nevertheless, the authorities, both north and south of the border, have caught up with 'Slab' Murphy.
Since then, Gerry Adams has denied that Murphy was a criminal, saying: "I don't believe that people who were involved in the IRA, if he was involved in the IRA, are criminals." He also described 'Slab' Murphy as "a good republican".
Even Mary Lou McDonald TD, vice-president of Sinn Fein, ended days of silence by supporting her party president and his statement that Murphy was "a good republican".
Sinn Fein believe that they have peaked in Northern Ireland and have a better chance of growth in the Irish Republic. However, the stench of criminality will undoubtedly damage the standing of the party south of the border.
Those are things that Mary Lou may well be thinking about as she wraps her presents and prepares her turkey.
As we move forward, criminals such as Murphy must be pursued vigorously, and the National Crime Agency (NCA) in the United Kingdom will have a major role to play.
For a long time, Sinn Fein opposed a role for the NCA in Northern Ireland, but eventually they had to cave in.
We must wish the NCA well in tackling paramilitary criminality - including republican criminality.