Woolmington v DPP [1935] AC 462

Reginald Woolmington's wife had left him and was living with her mother. Woolmington obtained a shotgun, shortened its barrel and went to the house. His wife was killed by a shot from the weapon. Woolmington said that he had intended to threaten to shoot himself in order to persuade her to return and that the gun discharged accidentally when he brought it from beneath his coat. At his murder trial, the judge directed the jury that, once the prosecution proved that Woolmington had killed her, it was for him to satisfy them that the shooting was accidental. He was convicted and sentenced to death. The Court of Criminal Appeal refused leave, and the Attorney General authorised an appeal to the House of Lords.

Did proof that Woolmington caused the death place the legal burden on him to prove accident, or did the prosecution have to prove the murderous intent?

The House of Lords quashed the conviction. Viscount Sankey explained that the prosecution must prove the prisoner's guilt, including the mental element of murder, subject to the defence of insanity and any statutory exception. An accused may have to raise evidence capable of putting a matter such as accident in issue, but the ultimate legal burden remains on the prosecution. If, on the whole of the evidence, a reasonable doubt exists about whether the killing was intentional, the accused must be acquitted of murder. The trial direction had wrongly treated malice as presumed from the killing and required Woolmington to disprove it. Because that misdirection went to the central disputed issue, the conviction could not stand.

The prosecution ordinarily bears the legal burden of proving every element of a criminal offence beyond reasonable doubt. The accused does not have to prove innocence merely because the physical act is established, subject to recognised common-law and statutory exceptions that expressly allocate a burden differently.

The decision's golden-thread principle underpins the presumption of innocence and criminal trial directions throughout the United Kingdom. It distinguishes the prosecution's persuasive burden from an evidential burden, under which a defendant may need only to produce enough material to make an issue live. Parliament may create reverse legal burdens, but courts interpret them carefully and must consider the right to a fair trial under article 6(2) ECHR. The insanity defence remains a notable common-law exception, while many other defences leave the ultimate burden with the prosecution once properly raised.