The Home Secretary is seeking to have the trial of a man accused of murdering a prize-winning author held in secret because the defendant may have links with British Intelligence, The Times has learnt.

Jacqui Smith has signed a “public interest immunity” certificate to have some or all of the trial for the murder of Allan Chappelow, the author of several books on the playwright George Bernard Shaw, held in camera. The highly unusual move is thought to be the first where such a “gagging order” has been sought in a murder trial.

Mr Chappelow, 86, a recluse, was found dead at his home in Hampstead, northwest London, in June last year under a pile of papers. A post-mortem examination showed that he had died from head injuries.

The defendant on trial for his murder is Wang Yam, 45, of Hampstead, who also faces charges of burglary and deception. Mr Yam, a financial trader, has pleaded not guilty to all the charges.

According to reports at the time, the author might have been the victim of identity theft before his death: it was said that bank officials tipped off police after becoming aware that Mr Chappelow had lost money from his account through a series of false transactions.

The Crown Prosecution Service has posted a notice at the Central Criminal Court in London, indicating that last week it applied for “part of the preliminary proceedings and trial” in the case of Regina v Wang Yam to be held in camera. The notice says: “The full grounds for the application are deliberately not set out in this Notice other than the order sought is to ensure the due administration of justice.”

All lawyers involved in the case are under orders not to discuss it. The trial is listed to take place on January 23.

A spokesman for the CPS confirmed yesterday that the PII application had been made. A hearing will be held on January 14 at which the application can be challenged — and a judge will decide whether the certificate should stand.

The general grounds under which public interest immunity may be claimed include the interests of national security and good diplomatic relations; protecting the identity of informants or sources of criminal intelligence; and where confidentiality is necessary in the interests of justice.

In the days before the discovery of Mr Chappelow’s body, £10,000 was reported to have been transferred from one of his bank accounts by a man claiming to be him. Four cheques, mail and a mobile phone were missing from his house in Downshire Hill, Hampstead. Nine days after his body was discovered on June 14, a fire broke out at the house, damaging up to 35 per cent of the ground floor and part of the basement and first floor. The house had become notorious among the smart neighbouring houses for its overgrown garden and ramshackle appearance.

Ian Leigh, professor at the human rights centre, Durham University, said that the signing of a PII certificate to have a murder trial or part of it in camera was highly unusual.

“There is a risk to the administration of justice when this happens. A trial is not a private matter: a very important aspect is that they should take place in public, particularly where public bodies are involved, because this acts as a spur to the highest standards by all involved.” He added that if it was impossible to have the trial in public without the evidence in question, then one consideration should be to drop the prosecution, “if the circumstances are such that either there would be damage to the public interest or the potential for an injustice”.

John Cooper, a criminal barrister and member of the Bar Council, said: “It is extremely unusual for any trial to be heard in camera. Open justice is one of the fundamental principles of the criminal justice system. For that to be compromised in any way means that there must be highly exceptional circumstances.”

Gagging orders

— PII certificates are normally used in trials to protect official secrets – and so they are often described as “gagging orders”

— After a minister signs a PII certificate to stop disclosure the issue then comes before a judge to decide whether the certificate can stand

— Public interest immunity, a principle of English common law developed by judges over the centuries, used to be called Crown privilege

— PII certificates may be used where evidence has been gathered in confidence, such as in child cruelty cases

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