These are still early days in coming to grips with the proposition that the UVF was boosted because some policemen thwarted murder investigations by their own colleagues for more than 10 years, apparently to protect a single informant; a serial killer and drug-dealer, writes Fionnuala O Connor.
How those immediately involved could have justified themselves and why their superiors would have given them free rein are only the simplest questions raised. In the week leading up to the ardfheis meant to decide Sinn Féin's official attitude to policing - last of the last hurdles - revelations about special branch collusion with north Belfast loyalists clanged like a great brass bell.
Drama in northern politics waned long ago, numbed by the slow progress towards settled politics. Some set-pieces are almost sepia-tinged in the memory, passage of time emphasised by departures.
One striking picture included the late David Ervine, for example, among the group of former loyalist paramilitaries who walked into negotiations with former Ulster Unionist leader David Trimble, to help Ulster Unionism refute the tag of "sellouts".
A couple of scenes this week reflected some of those recent bygones and a measure of the strengths and weaknesses of various players.
There was characteristic republican brass neck, plus a resoluteness sometimes absent in recent years, in the response to the report from Police Ombudsman Nuala O'Loan.
While unionist political reaction for the most part seemed muffled, Gerry Adams and Martin McGuinness pressed onwards. On air, and in the meetings organised ostensibly to debate policing but geared to steady supporters, leading Sinn Féin figures argued that the O'Loan revelations proved republicans should be inside the police to ward off collusion. Mostly, they have been heard attentively. Counter-arguments have made no headway. Faces in the crowds have looked wary above all.
The leaders join A to B with gossamer threads of rhetoric, but it takes unassailable personal testimony to protect their argument. When respected veteran Peter John Caraher gestured towards the platform party in Newry and wound up his contribution by saying he was looking forward to seeing them all in the police, "to make a different police force we can all be proud of", his own giddy-sounding giggle drew others in response before a wave of applause.
The mood of the meeting clearly was that the Caraher family had paid their dues: one son shot dead by soldiers, a second badly injured in the same disputed incident, then nine years later jailed for the attempted murder of an RUC officer. Mr Caraher told them he hated the RUC, so he was entitled to say it was time to join the rebranded service.
As people left, another elderly man confided that he saw the logic of the argument, but "you're dealing with very devious people here. I thought myself another couple of Canary Wharfs might do the trick". He whispered it, grinning at his own audacity. Initially defensive, angry unionist insistence that the findings of the ombudsman's report must not smear the entire record of the RUC became something else after Ms O'Loan met the supervisory policing board. Very difficult now not to take the report as credible, said Ulster Unionist representative Fred Cobain. Perhaps not that credible, said the DUP's Ian Paisley jnr, but "if there are problems, let's put them right".
The DUP may have to woo their voters, soon, into a new policing situation. Rev Ian Paisley has his pulpit: Gerry Adams on Wednesday had Clonard Monastery. Innocent Protestant citizens, seeing Clonard listed as a venue, might have supposed the main republican meeting scheduled for Belfast would take place in a hall in the monastery.
But no, as locals would never have doubted. The rooms where Mr Adams, John Hume and many others met over years to prepare the way for ceasefires and negotiations are all too small. The overflowing crowd on Wednesday filed into the pews of Clonard's great gilt-filled church, home of the annual novena.
A table covered in a white cloth for the Sinn Féin speakers sat on the huge sunburst of an altar, a speaking point nearby.
From the back of the church, first glance suggested Mr Adams was indeed in the pulpit, open-necked white shirt his concession to secular political imagery, dark jacket matching the rest of the platform party. No shirtsleeves as in Newry for Clonard.
The Sinn Féin leader milked every facet of the monastery's reputation, and remembered to omit Mr Hume when listing those associated with the place who "deserve great credit for the peace process".
More vocal critics in recent times may have a reputation as ultra-orthodox Catholic, but the ranks of dissent are scattered and incoherent. Mr Adams this week had the stage in Clonard, and a large section of his people - or so appearances tempt the onlooker to believe - in the palm of his hand.