Legal Case Summary
Sweet v Parsley [1970] AC 132
Absolute liability – Mens rea of a Statutory Offence under the Dangerous Drugs Act 1965
Facts
The appellant, Stephanie Sweet (S), was a sub-tenant of a farmhouse, where cannabis resin was found. S no longer lived in the house and had let out several rooms to tenants. She did retain a room but only returned occasionally to collect letters and rent. The appellant was charged and convicted under Section 5(b) of the Dangerous Drugs Act 1965 (1965 Act) with
“being concerned in the management of premises used for the purpose of smoking cannabis resin.”
Issue
Section 5(b) of the 1965 Act makes no reference to the mens rea required for the offence. The issues in question for the appeal court were (1) whether Section 5(b) created an absolute offence and (2) if not, what was the requisite mens rea for the offence. The appellant, S, appealed against her conviction, claiming that Section 5(b) required the mens rea of knowledge of the prohibited purposes which the farmhouse was being used for. While S accepted that the premises had been used for smoking cannabis resin, she had no knowledge of this use.
Decision / Outcome
Section 5(b) of the 1965 Act did not create an absolute offence. Unless it is the clear intention of Parliament that an offence is an absolute or regulatory offence (imposing strict liability), the presumption of mens rea prevails for ‘true’ crime offences. The words ‘being concerned in the management’ under Section 5(b) had to be read as importing a mens rea of knowledge as to the use of the premises for the prohibited purpose, therefore the offence was a ‘true crime,’ not a regulatory crime. The conviction was therefore quashed, as S, did not have the requisite mens rea for the offence under Section 5(b) of the 1965 Act.
Updated 20 March 2026
This case summary accurately describes the decision in Sweet v Parsley [1970] AC 132 and the legal principles established by the House of Lords regarding the presumption of mens rea in statutory offences. The core legal principle — that there is a presumption that mens rea is required for a ‘true crime’ offence unless Parliament has clearly indicated otherwise — remains good law and continues to be applied by the courts.
Readers should note that the Dangerous Drugs Act 1965, under which the charge was brought, was subsequently repealed and replaced, principally by the Misuse of Drugs Act 1971, which remains the primary legislation governing controlled drugs in England and Wales. However, this does not affect the authority of the case as a leading statement on the presumption of mens rea in criminal law. The case is regularly cited in this context and its authority is undiminished.
