The deal thrashed out between London and Sinn Fein over those suspected of involvement in historic acts of IRA terrorism was not exactly top secret, but nor was it advertised to the outside world.
Confirmation that it existed, coming in such a high-profile case, may have raised eyebrows – but the shockwaves today came not just from the exposure of the deal but the fact that the arrangements went so spectacularly wrong in the Downey case, apparently as a result of police error.
The net result, which has caused such a furore, was that the courts did not get to pass judgment on a man charged with involvement in multiple murder in London’s Hyde Park on 20 July 1982 – one of the darkest days of the Troubles.
Today was a deeply painful day for almost everyone concerned, from the families of those murdered to the various sections of authority involved in working a system which was supposed to function discreetly.
Serious questions have been posed about the administration of policing and justice, about police competence, and about dealing with vital matters away from political and public scrutiny.
The Hyde Park case can also be expected to bruise the Belfast peace process, already ailing as the two major parties in the Northern Ireland administration, the Democratic Unionists and Sinn Fein, are at loggerheads on many issues.
The details of the scheme which has now come to light will add volume to the refrain from unionists that Sinn Fein has managed to negotiate many unfair advantages from the peace process, some of them hammered out behind closed doors.
The Downey case is one of many which have been described as items of unfinished business arising from the Troubles in general and in particular from the IRA’s campaign of violence. His was one of almost 200 cases of “on the runs” left in limbo after the IRA ceased to be active.
It took many years of negotiation between Sinn Fein and successive governments, but especially under Tony Blair, to work out what is called “the administrative scheme”. It was based on the idea that individuals once classed as “wanted” would be given official letters of permission to allow them to travel outside Northern Ireland without fear of arrest.
This was quietly settled on after it became clear that many Westminster MPs disapproved of attempts to pass new legislation proposed by the Labour government.
The prisons had been virtually emptied of paramilitary prisoners by 2000 as a result of the 1998 Good Friday Agreement.
There was much criticism of the fact that hundreds of inmates – many serving life sentences for murder – benefited from early release provisions.
The releases were painful to many, especially the families of those killed and injured, although there was an element of balance in the fact that loyalists as well as republicans were set free.
Few of those released have re-offended, but there is still enduring resentment about this process.
However, the justification advanced by the Blair government, and accepted if not applauded by most of the population, was that conflicts do not end in satisfactory and just ways.
The argument was that the major republican and loyalist groups were unlikely to maintain their ceasefires if hundreds of their members remained behind bars.
Under the Good Friday Agreement it was decreed, after much heart-searching, that they should be freed.
But the Agreement covered only those in jail and not those “on the run,” and dealing with that major loose end took well over a decade.
Even then, as the Downey case has shown, the scheme has not laid to rest an issue which raises such hugely sensitive legal, political and, indeed, moral issues.