McKevitt is married to Bernadette Sands McKevitt, a sister of 1981 PIRA hunger striker and MP, Bobby Sands, who died during his hunger strike. Sands McKevitt was a leading member of the 32 County Sovereignty Movement and had been described in media reports as the third highest ranking Real IRA officer. However she also left the 32 County Sovereignty Movement following the imprisonment of her husband.
Mr. Justice Richard Johnson said of McKevitt, "[t]he accused played a leading role in the organisation which he directed and induced others to join." On 7 August 2003 he was sentenced to twenty years in prison. Given all possible reductions and remission, it means that the earliest he can be released is 2016.
McKevitt appealed his convictions to the Court of Criminal Appeal, arguing that Rupert's testimony was unreliable since he had been paid large sums of money for his role as an informant (a total of £750,000 from the FBI and MI5), and because of Rupert's long criminal record. In December 2005, the court rejected these arguments and said that Rupert was a credible witness. Both of McKevitt's convictions were upheld. In July 2006 McKevitt was given leave to appeal to the Supreme Court. The appeal was rejected on 30th July, 2008.
McKevitt was expelled from the Real IRA after a disagreement between a group of Real IRA prisoners in Portlaoise Prison and the outside leadership. The prisoners issued a statement urging the leadership to stand down claiming a criminal element had taken over. McKevitt and his supporters went on to form a group called The New Republican Forum.
Previous to his arrest and jailing, McKevitt resided at Beech Park, Blackrock, County Louth. A website launched to highlight McKevitts case was launched in June 2006.