In the annals of Ulster's Dirty War the role of the Military Reconnaissance Force ranks as one of the strangest, murkiest and morally dubious episodes of the early conflict. Not only did the undercover army unit deploy special forces soldiers in civilian clothing to carry out surveillance and even shootings on the streets of Belfast, they also recruited agents from within paramilitary organisations to do much of their dirty work.
The French had a word for them: 'Agents Provocateurs'. The British had a more prosaic name for such men - they called them 'Freds'. The 'Freds' were often 'turned' IRA activists and other paramilitaries, often in their teens and very early 20s. They were arrested, interrogated and offered deals to join the MRF in return for not being charged with terrorist offences and facing either internment or even longer prison sentences if convicted of particular crimes.
At least two men are believed to have been killed by MRF operatives, Daniel Rooney and Patrick McVeigh, both shot dead in disputed circumstances in 1972 in west Belfast. Several other men were victims of MRF drive-by shootings and targeted attempted assassinations during the earliest and most bloodiest part of the Troubles. Their relatives have been seeking answers as to what happened to their loved ones at the hands of this covert, secretive military controlled unit.
Were they killed or wounded by actual soldiers dressed up in the fashions of the early 70s with their flared trousers, winged collared shirts and long wavy haircuts?
Or were their relations targeted by young men from their own communities used as pawns in Britain's counter-insurgency war, some of whom, like two of the Disappeared, ended up losing their lives at the hands of the IRA?
The families and close friends of the victims of the MRF have, of course, every right to demand the truth as to what happened to these men back in the very early 70s.
The problem again, however, with the PSNI's intervention in this particularly shadowy and sinister episode of the Troubles is that it will open up the police and indeed the government to charges of double standards. It would be worth asking the PSNI's Legacy Branch exactly how many officers have been assigned to this specific investigation.
Unionists and victims of massacres will claim there is a heavy bias in favour of historic inquiries into murders committed by the state or the loyalists. They could point, for instance, to the fact that at present the historical inquiry into the IRA's massacre of 11 Protestants at Enniskillen on Poppy Day 1987 has run into the sand and that, at present at least, not a single PSNI officer sits on the Legacy Branch's 'Enniskillen desk.'
In addition to accusations of double standards and bias is the clash between the demands of truth and justice. Just as the seizure of the Boston College tapes by the PSNI landed a mortal blow on the idea of an open, truth-telling mechanism where 'combatants' of all hues, IRA, UDA, UVF, INLA, RUC, UDR and British Army, could tell their stories openly and truthfully, so with each attempt to prosecute ex-players in the tragedy from 1969-1994 hammers another nail into the coffin of a Truth and Reconciliation Commission.
Moreover, the more one side perceives that the arrests and criminal/historical inquiries are skewed in one direction the greater the danger that someone in the security apparatus from the past is going to leak something deeply embarrassing and, potentially, truly destabilising about their former enemies and who they were really working for.