Mischief rule
The mischief rule is one of three rules of statutory interpretation traditionally applied by English courts, the other two being the "plain meaning rule" and the "golden rule". It is used to determine the exact scope of the "mischief" that the statute in question has set out to remedy, and to guide the court in ruling in a manner which will "suppress the mischief, and advance the remedy".
The rule considers not only the exact wording of the statute, but also the legislators' intentions in enacting it. In applying the rule, the court is essentially asking whether parliament in enacting the statute intended to rectify a particular mischief, even though it might not be covered by a literal reading of the statute's wording. For example, if a law prohibits a specific behaviour "in the street", the legislators might – or might not – have intended the same behaviour on a first-floor balcony overlooking the roadway to be covered.
The rule was first set out in Heydon's Case, a 1584 ruling of the Exchequer Court.
Meaning and use
In Conway v Rimmer it was observed that judges can apply in statutory interpretation in order to discover Parliament's intention. In applying the rule, the court is essentially asking what the mischief was that the previous law did not cover, which Parliament was seeking to remedy when it passed the law now being reviewed by the court.The mischief rule is of narrower application than the golden rule or the plain meaning rule, in that it can only be used to interpret a statute and, strictly speaking, only when the statute was passed to remedy a defect in the common law.
Legislative intent is determined by examining secondary sources, such as committee reports, treatises, law review articles and corresponding statutes.
The application of this rule gives the judge more discretion than the literal and the golden rule as it allows Parliament's intent to be taken into consideration.
That the mischief rule can produce different outcomes than those that would result if the literal rule were applied is illustrated by Smith v Hughes 2 All E.R. 859. Under the Street Offences Act 1959, it was a crime for prostitutes to "loiter or solicit in the street for the purposes of prostitution". The defendants were calling to men in the street from balconies and tapping on windows. They argued that as they were not themselves "in the street" they fell outside the definition. The judge held that as the intention of the act was to cover the mischief of harassment from prostitutes, the quoted wording did apply, and the defendants were found guilty.