The Literal Rule
The literal rule is used by judges to look at the literal meaning of words in an Act. Lord Escher expressed similar views to this rule in R V Judge of the City Of London Court saying "if the words of an Act are unclear you must follow them even though they lead to a manifest absurdity"
The Golden Rule
The golden rule also looks at the literal meaning of words of an Act but allows the court to avoid an interpretation which may lead to an absurd result.
Their are two applications of the golden rule:
1.The Narrow apllication
This is used when there are ambiguous words involved in the Act, and this application allows the court to choose the most suitable meaning of the ambiguous word/phrase to avoid an absurd decision from occuring. (example of use in: R v Allen)
2.The Broad/wider application
This application is used when words in an Act have one clear meaning, but that meaning would lead to a repugnant situation (Such as in the case of Re Sigworth) and the golden rule will then be used to change the words in the Act to avoid this situation from occuring.
The Mischief Rule
Derives from Heydons Case and involves looking at Parliament's intention for the Act, by determining the defect that the statute in question is trying to remedy.
(Used in Smith V Hughes)
The purposive approach
This rule goes further than the mischief rule in that it not only allows judges to look at the defect that the statute in question is trying to remedy, but also it allows judges to decide what they believe parliament wanted to achieve. (it creates more scope for undemocratic law making).
This rule was used in R (Quintavalle) v Secretary of State.