R v Hennigan [1971] 3 All ER 133
Death by dangerous driving – cause of accident – Road Traffic Act 1960 section 1
Facts
Hennigan drove at eighty miles per hour and hit the side of a car, driven by Lowe, who was emerging from a turning in a road. Lowe’s two passengers died from the collision. The accident happened at around 11.00pm in a restricted area. Hennigan was found guilty on two counts of causing death by dangerous driving, by a verdict of ten to two, fined £25 on each count and banned from driving for five and a half years. He appealed the conviction.
Issues
Had this been a civil claim, Lowe would have been substantially to blame because she was at fault when emerging from the minor road. The trial judge directed the jury to establish two elements. The first was whether the manner of Hennigan’s driving was dangerous or not and secondly that the dangerous driving had caused the accident in question. Importantly, the judge instructed the jury that a key determination was whether the dangerous driving was a ‘substantial cause’ of the death of the two passengers in Lowe’s car. The jury also sought further clarification from the judge as to the definition of ‘substantial’.
Decision/Outcome
The court emphasised that there is nothing in the Road Traffic Act 1960 section 1 which requires driving to be the substantial or even major cause of an accident. Providing the driving was something more than de minimis, the legislation is in effect. The court also supported the five and a half year driving suspension based on the fact that Hennigan was only twenty years old and already had been convicted for motoring offences.
Updated 20 March 2026
This article accurately summarises the decision in R v Hennigan [1971] 3 All ER 133 and the legal principle it established regarding causation in dangerous driving cases. The core principle — that the dangerous driving need not be the substantial or major cause of the accident or death, provided it is more than a de minimis cause — remains good law and continues to be cited in causation discussions in criminal law.
However, readers should note that the statutory basis of the offence has changed significantly since 1971. The Road Traffic Act 1960, under which Hennigan was charged, has long been repealed. The offence of causing death by dangerous driving is now found in section 1 of the Road Traffic Act 1988 (as substituted by the Road Traffic Act 1991). The maximum sentence has also been substantially increased over the years; it now stands at 14 years’ imprisonment following the Police, Crime, Sentencing and Courts Act 2022, which also introduced the new offence of causing serious injury by careless driving. The article’s reference to the 1960 Act is therefore historically correct for the case itself but students should be aware that the current statutory framework is materially different.
