What considerations must a judge consider before making a decision in the exercise of discretion?

It is, of course, recognized that courts can lay down factors to be considered in the exercise of discretion, while they cannot lay down rigid rules. Thus, in Ward v. James, [1965] a1 All E.R. 563, Lord Denning, M.R. stated at p. 571: The cases all show that, where a statute gives a discretion, the courts must not fetter it by rigid rules from which a judge is never at liberty to depart. Nevertheless the courts can lay down the considerations which should be borne in mind in exercising the discretion and point out those considerations which should be ignored. This will normally determine the way in which the discretion is exercised and thus ensure some measure of uniformity of decision. From time to time the considerations may change as public policy changes, and so the pattern for decision may change. This is all part of the evolutionary process.