Prison staff bugged conversations between a convicted killer and his solicitor without authorisation, Jack Straw admitted yesterday.

The privileged telephone calls made by Harry Roberts, 72, were recorded at Channings Wood prison in Devon in 2005 and 2006. The Times disclosed the extent of the bugging in February, reporting that the transcripts of the conversations came to light only because they were disclosed to Roberts’s solicitor, Simon Creighton, as part of his long battle to win parole.

The Justice Secretary told MPs that an inquiry had found that Roberts, who is serving life for killing three police officers in 1966, had failed to identify his solicitor’s number to staff, which Roberts denies. Conversations between prisoners and legal advisers are privileged and can be taped only if authorised by the prison governor in exceptional circumstances.

Mr Straw said: “There was no authorisation to intercept, record and monitor the legal telephone conversations.” He said that the rules were being changed and that authorisation for the interception of legal calls would now be decided by the chief operating officer of the National Offender Management Service.

Mr Straw also disclosed that police had taped Roberts’ conversations with legal advisers without authorisation.

Mr Creighton said that his client welcomed Mr Straw’s statement.

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