Statutes remain law until they are repealed by Parliament. Sometimes this creates absurdities like [[Ashford vthornton 1818]] (right to trial by combat), and [[Prince ernest of hanover vattorney general 1957]], and Parliament normally moves to repeal such legislation rather quickly.
* The principle of ejusdem generis applies if the passage can be so read; that is, where a statute provides a list like `X, Y, and similar Zs', then it will only apply to an item not on the list if it really is of the class Z. For example, `cats, dogs, and other pets' probably excludes lions (as not being pets), but it is not clear whether `cats, dogs, and other animals' would include lions (see the specific entry for [[Ejusdem generis]] for more details).
* The principle of expressio unius est exclusio alterius (``the expression of one is the exclusion of others'') applies. So, for example, ``land and coalmines'' does not include slate mines, because if that meaning were intended that clause would have been ``land and mines''.
* Statutes are assumed not the alter the common law, unless this is stated explicitly. Of course, many statutes are created specifically to alter the common law, and the `mischief rule' relies for its effect on this fact.
* Statutes are assumed not to violate international law; however, if the wording is clear a court cannot disapply a statute even if it is in flagrant violation (e.g., [[R v environment agency ex parte marchiori 2002]]).