The recent scandal of secretly recorded conversations between the lawyer Simon Creighton and his client raises the question: why do we have the principle of “professional privilege” protecting the lawyer-client relationship?

In essence, it means that communications between a lawyer and client are confidential and can only be revealed to a court or the police if the client wants them to be. It is a protection greater than that given to doctors and patients, priests and penitents or accountants and their clients. The word “privilege” comes from the Latin (privilegium) for “private law”, a law applying to an individual or small group. Under general law, what citizens say to each other can be used in evidence in court. A “private law” though applies to lawyers, and gives lawyer-client communications a specially guarded confidentiality.

The justification is simple and compelling. You don’t want to live in anarchy, you want to live in a society of laws and rules. As there are thousands of laws, you don’t want to have to become an expert yourself on them all, anymore than you want to learn medicine just so you can be your own doctor. You want experts on the laws: lawyers. Society should encourage citizens to go to its lawyers for advice whenever they are in difficulties. To ensure the lawyer-client relationship works well, there must be complete trust, and, in order for that to happen, the client must feel assured that client-lawyer communications are completely private and confidential.

It isn’t a question of “if a client has done nothing wrong, they’ve got nothing to worry about if their chats with their lawyer are recorded”. To be full and frank with lawyers in criminal, family, civil, and commercial cases, many clients have to mention secret, embarrassing or compromising things that are incidental to their main stories. But more good is served by those things remaining confidential, and the law taking its proper course guided by lawyers, than if clients were deterred from telling the big truths to lawyers for fear of the incidental compromising facts being open to be made public.

The rule of privilege is long established. In Greenough v Gaskell (1833), Lord Brougham, the Lord Chancellor, said that the rule was important to uphold “the interests of justice”. He said if the rule didn’t exist, people would be mistrustful of consulting legal experts and so would end up worsening their own positions with do-it-yourself law. As he put it, “everyone would be thrown upon his own legal resources”.

More recently, in 2003, the Privy Council (the highest appeal court for many Commonwealth countries) ruled that lawyer-client privilege is fundamental to the operation of justice and shouldn’t be overridden unless the law has specifically said so in that particular circumstance. The privilege is also protected under European law and European human rights law.

The privilege against disclosure doesn’t, however, cover all communications. In a case in 1884, an English appeal court confirmed that if a client asks a lawyer for information in order to be guided on how to commit a crime, the lawyer can testify about that despite the client’s protests.

Henry Munster, who’d been libeled in The Brightonian, was awarded damages. But the publisher of the paper, Richard Railton, conspired with a business partner to make a property transaction in order to avoid paying the damages. Railton had asked his solicitor some questions in preparation to do something unlawful. Informed, for example, that he wasn’t allowed to sell property to his own business partner, Railton asked the solicitor “Does anyone know about the partnership except for you?” After the scam was exposed, the solicitor was called as a prosecution witness and Railton and his partner were convicted.

Allowing client-lawyer privilege doesn’t, as is sometimes said, amount to allowing criminals to thrive. A lawyer cannot assist in the commission of a crime or say to a court anything he knows is untrue — those are very serious offences. Plus, it’s a lawyer’s positive duty to disclose information that he knows or suspects relates to particular crimes such as terrorism (under the Terrorism Act 2000) or money laundering (under the Proceeds of Crime Act 2002).

Sometimes, of course, that puts lawyers in a difficult position. The barrister Rayner Goddard (who became Lord Chief Justice in 1946) asked his first client, during their initial cell interview at the Old Bailey: “Now, my man, what is your story?” The client replied “Well, that’s rather up to you, guv’nor.”

It might be that the privilege rule means that lawyers get to hear some immoral or shocking things about the lives of some clients, and that those remain secret. But that’s a small price to pay for a population knowing that the state doesn’t have its eye and an ear in the very offices where citizens go when they need help.

Professor Gary Slapper is Director of the Centre for Law at The Open University

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