Interim guidance by the GMC and the Department of Health on the reporting of knife wounds is timely and appropriate, says the MDDUS.

The guidance says that a doctor treating a patient with a wound "inflicted in a violent attack with a knife, blade or other sharp instrument" should inform the police. If in doubt about the cause of an injury, consult a colleague.

"The difficulty is that you as a doctor may have suspicions how the patient received an injury, but have no real evidence," says MDDUS medico legal adviser George Fernie. "Clearly there are occasions when the cause of an injury is fairly obvious, but on other occasions it may be more obscure."

Obviously, a doctor should comply with GMC guidance to disclose where a failure to do so may result in death or serious harm to another individual but the proposed approach has a degree of ambiguity and may dent public confidence if it deters a potential patient from seeking medical care.

GMC/DoH guidance adds that police should not be informed in cases of accidental injury, or a result of self-harm, but that quick reporting of "suspicious" wounds may help prevent further incidents or harm to others.

"Under the guidance, a doctor appears to have to tell the police of the arrival of a patient with a knife wound without delay. The police then attend as a result ("when the police arrive..", as the guidance puts it). However, under the guidance, no further information, including the name and address of the patient, can be disclosed without consent: if the GMC guidance says the doctor "must" respect the patient's desire for anonymity, that amounts to an overriding duty or principle. But how can such limited disclosure, which would pile more pressure on to busy medical staff, assist the police?

"Doctors are expected to act responsibly as members of society. Guidance can help to explain the issues where doctors have sometimes conflicting choices to make. However, this interim guidance lacks such finesse. We need to see more of the GMC's reasoning, bearing in mind the day-to-day practicalities faced by doctors, patients and the police."

When in doubt members should seek advice from MDDUS, especially until there is greater clarity.

MDDUS is a medical defence organisation providing access to professional indemnity and expert medicolegal advice for doctors, dentists and other healthcare professionals throughout the UK. For further information on MDDUS go to mddus.