The police have gone to great lengths to argue that the identities of their undercover officers must be concealed forever.



However it was the police themselves who are responsible for helping to unmask the latest undercover officer whose identity has been confirmed.

The public inquiry into undercover policing confirmed last Wednesday that Roger Pearce had been an undercover officer for the Special Demonstration Squad (SDS). He had used the fake identity of “Roger Thorley” during his deployment.

A vital clue about his undercover deployment was given by the police in an official report four years ago. The police conducted an internal investigation into the SDS which deployed undercover officers to infiltrate hundreds of political groups between 1968 and 2008.

Former commander and undercover spy Roger Pearce

One of the reports arising out of this internal investigation was published by police in 2013. It examined the theft of dead children’s identities by the undercover officers following criticism of the technique.

A number of anonymous former SDS officers were quoted in the report about how they had used the identities of dead children during their undercover work. Each officer was assigned a codename in the report to protect their anonymity.

The description of one of these officers was however curious. The officer given the codename N85 was described as being an undercover officer in the SDS between 1978 and 1980. However he was also described in the report (see para 7.2) as being the head of Special Branch between 2000 and 2004.

Once that crucial clue had been disclosed, there was enough in the public domain to show that Pearce had been head of Special Branch at that time and was therefore the undercover officer being referred to as N85.

For example, Pearce crops up in news reports here and here as being head of Special Branch in 2000 and 2001.

The first public identification of Pearce as N85 appears to have come in 2014 by Bristol-based blogger, BristleKRS (see here).

Pearce had himself developed a public profile around 2013, appearing in the media to defend the SDS on a number of occasions. He did not say he had been an undercover officer, although his tenure as the head of Special Branch at that time was given (see for instance this BBC article).

The Undercover Research Group, the network of activists that investigates the covert infiltration of political groups, has collated what is known about Pearce in one of its characteristically detailed profiles that was published last year. This blog by the group also examines how Pearce defended the SDS during his media appearances.

Given their strenuous efforts to keep secret their covert officers, it is unclear why police gave away a big clue to Pearce’s undercover identity - it suggests either incompetence or laxness.

Roger Pearce talks about why he writes about Special Branch in his novels.

The groups that Pearce infiltrated are not publicly known yet. However the Guardian understands that he went undercover between 1979 and 1984 (the usual length of deployment for an SDS officer), not the years stated in the police report. The dates given for his tenure as head of Special Branch in the police report are also slightly awry (as he was actually in charge between 1999 and 2003).

Since leaving the police, Pearce has become an author, drawing on his experiences in Special Branch, to write thrillers. His third book - Javelin - is due out in July. He has his own website. Here’s a review of one of his books, Agent of the State.

More than 100 undercover officers have been deployed to infiltrate political groups since 1968. Pearce was the sixth undercover officer whose identity has been confirmed by the public inquiry, although all six had previously been exposed by activists and journalists. The public inquiry is led by Lord Justice Pitchford.

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