The Law Society is lobbying the Labour Party to oppose parts of the Police Bill, saying the proposed legislation will destroy the relationship between solicitors and their clients and breach civil liberties.

The Law Society president Tony Girling will voice concerns about the Bill in an open letter to shadow Home Secretary Jack Straw this week.

But there are already indications that the lobbyists' message has been heard, with announcements on the Bill from both parties expected today (14 January).

The Police Bill, which aims to regulate the use of surveillance equipment, will allow police to secretly bug conferences between a solicitor and his clients and to use any information obtained as evidence in court. Although bugging of solicitors' offices already happens informally, any information obtained is currently inadmissible.

Labour is expected to propose an amendment so that permission to bug solicitors' conversations with their clients can only be given in cases where there is a strong likelihood of an abuse of legal professional privilege.

Chris Philipsborn, head of the parliamentary unit at the Law Society, welcomed Labour's new stance but acknowledged that the formula remained quite vague.

He said the society was concerned because surveillance equipment installed in a solicitor's office ran all the time and recorded information about every client indiscriminately.

“The use of surveillance equipment will destroy the trust between a lawyer and a client ,” said Philipsborn. “The issue of confidentiality also affects City firms who deal with international clients. If they can no longer guarantee confidentiality, clients will go elsewhere.”

The society is also campaigning to ensure that responsibility for authorising the use of listening devices rests with judges and not with chief constables as the Home Office originally proposed. “We do not want this to go on at all but if it must happen we would much prefer it if the judge gives authorisation,” said Philipsborn.

The Law Society plans to hold an information session for both Houses on the Police Bill after it has gone through its report stage in the Lords at the end of the month.