The 1980 Walker report on RUC Special Branch has been something of a holy grail for documentary researchers of the Troubles. After a long-running campaign, the Committee for the Administration of Justice has published a redacted version (PDF) released by the Police Service of Northern Ireland.
The Rights NI blog has a valuable analysis of the document by Brian Gormally:
All in all, the Walker Report is a blueprint for how to turn a police force into a conflict-fighting weapon where victory against the “subversives” is the overriding priority and traditional functions such as preventing crime and upholding the rule of law are sidelined.
As Gormally notes, there is no mention in the report of Walker's own organisation, MI5.
According to the Civil Service Yearbook for 1980, Walker was a member of the Northern Ireland Office Liaison Staff. This was headed by a Deputy Secretary, J Parker, and included 3 assistant secretaries, P Walker, M. McGlashen and H. Magnay.
We know from a number of inquiries that the liaison staff was actually the department of the Director and Co-ordinator of Intelligence (MI5), who was usually drawn from MI5.
David Leigh reported that a John Parker was DCI in the late 1970s. Intelligence writer Stephen Dorril has reported that Harold Magnay was head of MI5's C4 counter-sabotage section in the early 1980s. Maureen MacGlashen was diplomat who served in Tel Aviv, East Berlin, and Brussels before being seconded to the Home Civil Service in 1977.
Patrick Walker himself became head of MI5 in 1988. According to Dorril he had served as a Deputy DCI under David Ranson, who was probably Parker's successor.
The DCI also had representatives at RUC and Army HQ Northern Ireland. We don't know the names of any of the former, although David Eastwood held the analogous role of Security Liaison Officer in 1970. The HQNI post was held by Ian Cameron in the mid-1970s. (By the early 1980s, Cameron was embroiled in the RUC investigation of Kincora, something which created ongoing problems for MI5.)
The DCI's representative to the RUC must have had a close relationship with Special Branch but this goes unmentioned in the report.
Clues to MI5's role may be buried in the redactions. Some of these labelled 'S1' appear to refer to a similar document compiled some time earlier.
This could be a reference to the still unreleased Morton Report of 1973. As Phil Miller has noted, this was compiled by the MI5 officer and former Indian policeman Desmond Morton. The career progression from colonial service to MI5 was an extremely common one in this period, aided by MI5's own colonial role and by the retreat of empire. Walker himself had begun his career in Uganda.
The question naturally arises therefore, how far the model that MI5 promoted in the RUC was based on the service's extensive experience of colonial special branches.