The long-running police operation to infiltrate political groups continued to unravel this week, after the Director of Public Prosecutions disclosed that a second group of environmental campaigners may have wrongly convicted.

On Tuesday Keir Starmer, the DPP, announced that a senior prosecutor may have withheld vital evidence about police spy Mark Kennedy from another trial of activists.

As we reported here, Starmer has invited the 29 activists convicted in 2009 over a protest at the Drax power station to challenge their convictions at the court of appeal.

This is potentially a significant development that begins to undermine the official line that the first case, the Ratcliffe-on-Soar miscarriage of justice, was a one-off, isolated failure by police and prosecutors. Starmer’s announcement may be the beginning of the end for the “one rogue prosecution” argument propagated by the authorities. It in effect concedes that the controversy over the undercover policing of protest groups could be bigger than police and prosecutors have so far been willing to admit.

To recap, the court of appeal last year quashed the convictions of 20 campaigners who had been plotting to occupy the Ratcliffe-on-Soar power station in Nottinghamshire in 2009. The judges ruled that basic principles of justice had been ignored as prosecutors and police withheld key evidence which could have acquitted the campaigners. That evidence consisted of secret recordings made by Kennedy of the activists’ private meetings. The appeal court judges said they shared the “great deal of justifiable public disquiet” about the case.

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