THE contours of the criminal law need to match most people’s ideas of right and wrong. In recent weeks, both in Britain and France, the boundaries of what amounts to a crime have come under heated courtroom debate.

In one case a “sleepwalking” man who crashed his car into a wall was acquitted of drunken driving, and in the other a drunk man found asleep in his van had his conviction for being “in charge of a vehicle while unfit” confirmed.

William Bough, 48, a Gulf War veteran, was three and a half times over the legal limit but magistrates acquitted him after hearing evidence from a clinical psychologist that he had been sleepwalking. Bough, of Garstang, near Preston, told West Allerdale and Keswick Magistrates’ Court that he had no memory of getting into his car or of the crash, in which he hit a wall at Lillyhall, Workington. The expert evidence, including a 17-page report on Bough’s condition, convinced the bench that the defendant was suffering from somnambulism and was probably “sleepwalking” at the wheel when the accident happened last year. The case was dismissed after a five-hour trial.

The court was told that Bough had been suffering from post-traumatic stress disorder since the Gulf War. He had been staying with his mother so that he could accompany her when she was admitted to hospital the following day. He admitted to having had “a few drinks”. After the crash, he was found dressed in a T-shirt that he normally wore in bed. He had also left his driving glasses in his overnight bag.

The law offers a defence of automatism to defendants who can show that their behaviour was involuntary. Somnambulism is a form of automatism, in which behaviour does not flow from conscious decisions or will. It has been clearly recognised by the courts as a defence since 1961. The somnambulism defence is, though, not always without consequence for the defendant. In 1991, at Bristol Crown Court, Barry Burgess was sent to a secure hospital after being found “not guilty by reason of insanity” of having brutally attacked a woman neighbour while sleepwalking. This unusual verdict reflected the fact that his somnambulism had not been triggered by an external event but had developed in him organically. In 2002 the Court of Appeal confirmed that if external factors (such as the taking of prescription drugs and drink) operate on an underlying condition that would not otherwise produce a state of automatism then the defence is possible and should go to a jury.

A different principle arose in the case of Peter Sheldrake, of Hatfield Peverel, Essex, who was found asleep in his van in a car park in 2001. He claimed that he had made attempts to arrange alternative transport home but was convicted at Colchester Magistrates’ Court of being in charge of the vehicle while unfit, and given 160 hours of community service. Sheldrake failed to convince the magistrates that he had not intended to drive the vehicle, and later complained that he should not have to prove his innocence.

Upholding the conviction, the House of Lords has ruled this month that the charge under the 1988 Road Traffic Act did not infringe the right to a fair trial provided for in Article 6(2) of the European Convention on Human Rights. There was in the charge no irrebuttable presumption of guilt, and defendants were given a reasonable scope to exonerate themselves. Lord Bingham of Cornhill ruled that the offence of being “in charge while unfit” did not require proof from the prosecution of an “intention to drive”. There were, he noted, many instances of legislation in which “Parliament has clearly intended to attach criminal consequences to proof of defined facts, irrespective of an individual’s state of mind”.

Strasbourg jurisprudence has also condoned such laws. In a 1988 decision it was noted that the contracting states could “penalise a simple or objective fact, as such, irrespective of whether it results from criminal intent or from negligence”. Lord Bingham explained that in cases such as those of “being in charge of a vehicle while unfit”, the task of the court was to “assess whether a burden enacted by Parliament unjustifiably infringes the presumption of innocence”. In this case, bearing in mind the seriousness of the wrong to be controlled, and the opportunity of the defendant to rebut the charge (by showing that there was no likelihood of his driving while drunk), the Act was proportionate to the mischief to be addressed. Lord Bingham noted that a person in charge of a car when unfit would be expected to hand the keys to someone else or stay well away from his vehicle.

In 1935, in his entertaining Misleading Cases, A.P. Herbert wrote that “there is no juridical distinction between firearms, wild beasts, and motor cars where the safety and peace of the King’s subjects on the King’s highway are concerned”. Indeed, the elegance and logic of much legal reasoning are no more obvious to all at first sight than is the science of computer programming, but they can usually be discovered with study.

The author is Professor of Law, and Director of the Centre for Law, at the Open University

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