The island’s chief constable, Mike Culverhouse, said: “The gravity of the issue at stake here cannot be exaggerated.”
The deputy chief constable, Neil Kinrade, was suspended two weeks ago, apparently over the issue. Mr Kinrade has lodged an official complaint against Mr Culverhouse, saying he had been suspended “on questionable grounds”, and is seeking legal advice. He has also complained of trial by media and categorically denies inappropriate or unlawful conduct.
An independent investigation is being conducted by Cheshire police, who were brought in last month to investigate seven complaints against the force.
Mr Culverhouse said that reports suggested use of the listening device was common until the spring of 1999. “It is imperative that this matter is subjected to the most thorough, independent and comprehensive investigation possible.
The chief constable ordered a search of police headquarters on Monday, but no devices were found.
Franklin Sinclair, a defence lawyer in Manchester, said it was not uncommon for police forces to secretly record conversations. “It is totally illegal and is a breach of the Police and Criminal Evidence Act codes of practice, which give a person the right to legal advice in private. It tears at the fabric of the justice system. We should have privacy in which to advise our clients.
“We have had cases where prison cells have been bugged and when we have found out, they say it was an accident. I would not be surprised if it goes on in other forces in England and Wales.”
In January 2002, five men accused of a gangland murder plot in Lincolnshire walked free after it emerged that police had illegally taped them talking to their lawyers.
The judge threw out the £3m trial after ruling that Lincolnshire police had broken the law. “Justice has been affronted in a grave way,” said Mr Justice Newman.
Andrew Corlett, president of the Isle of Man Law Society, said that if the allegations were proven, some convictions over the period would need to be reviewed. He said the overwhelming majority of officers were decent and professional. “It is … these high standards that give such an alleged departure its powerful and shocking resonance.”