Sweet v Parsley

Sweet v Parsley, [1970] AC 2 was an English legal case where the defendant was found guilty of allowing her property to be used for smoking cannabis. Even though she had no knowledge of the offence, it was on her property so she was liable without fault. This conviction was later quashed by the House of Lords on the grounds that knowledge of the use of the premises was essential to the offence. Since she had no such knowledge, she did not commit the offence.

It is significant in English criminal law as it sets out a new set of guidelines for determining strict liability. Lord Reid laid down the following guidelines for all cases where the offence is criminal as opposed to quasi-criminal:
 * 1) Wherever a section is silent as to mens rea there is a presumption that, in order to give effect to the will of Parliament, words importing mens rea must be read into the provision.
 * 2) It is a universal principle that if a penal provision is reasonably capable of two interpretations, that interpretation which is most favourable to the accused must be adopted.
 * 3) The fact that other sections of the Act expressly require mens rea is not in itself sufficient to justify a decision that a section which is silent as to mens rea creates an absolute offence. It is necessary to go outside the Act and examine all relevant circumstances in order to establish that this must have been the intention of Parliament.