There is no doubt that MI5 knew about the Kincora sex abuse scandal and kept it quiet.
For evidence we have the testimony of a man described by MI5 itself as an energetic, reliable and brave source of intelligence who had proved himself on many occasions. This praise was heaped on the head of a man known as 'Observer B' at the Bloody Sunday tribunal.
"My case officer told me to leave McGrath to them and I have always believed they used the information (about his sexual activities) to recruit him as an informer," Observer B told me.
He was referring to William McGrath, the housemaster of Kincora Boys' Home and one of three men later jailed for abusing youngsters in his care. Observer B, who had supplied a dossier to MI5, was promptly told to leave McGrath's Tara paramilitary group and join the UDA.
The person praising Observer B to Lord Saville's tribunal was one of his former handlers, a career MI5 agent known as 'Julian'. His evidence, which was given in London in May 2003, is preserved in the National Archives and available online.
Julian made it clear that Observer B, although not a republican, was a prized security service informant in Londonderry at the time.
Observer B was a former British Army Sergeant Major, an Englishman married to a local woman. He died in 2003, but I spoke to him in 1987 about his efforts to alert the authorities to Kincora before his handlers made his financial problems disappear to shut him up.
There was immediate confirmation of his status when Admiral William Higgins, Secretary of the Defence Advisory Committee, warned me that giving the man's whereabouts or naming his handlers would be a breach of national security and punishable as such.
But he wasn't the operative who tried to raise Kincora.
In May 1987 I published the story of a former Field Intelligence Non Commissioned Officer (FINCO). Unlike Observer B this FINCO is still alive.
In 1976 he was posted to east Belfast and became aware of Tara and McGrath. He posted a report to senior officers who told him to take no action.
McGrath had first come in contact with the intelligence community in the 1950s when he smuggled Bibles into Russia.
His handler was said to be an MI5 officer working in Old Holywood Road who was later charged with an offence against a young boy.
Such issues cannot be let lie.
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