The process by which judges have to decide the meanings of words or phrases in Acts of Parliament or other legislation. Although, when laws are drawn up, the draftsman tries to make them as clear as possible, there are still many problems which can occur so that the meaning is unclear. These are:
• a broad term: there may be words used to cover several possibilities, and it is difficult to decide exactly what it does cover;
• ambiguity: some words may have more than one meaning, and it is difficult to decide which is meant in the Act;
• a drafting error or omission: there may be a mistake which makes the meaning uncertain, or an omission so that a situation which should be included appears not to be;
• new developments: new technology may mean that an old Act of Parliament does not apparently cover the situation;
• changes in the use of language: the meanings of words change over the period of time.
Judges have different approaches to statutory interpretation. Some will take the literal meaning of the words, others will look beyond the words to try to discover what the law was meant to include. See also literal rule , golden Rule , mischief rule and the purposive approach . There are also rules of language which are used in trying to decide meanings of words and phrases. These are ejusdem generis , expressio unius est exclusio alterius and noscitur a sociis .