AP Picture Houses v Wednesbury

[judgment transcript http://www.bailii.org/ew/cases/EWCA/Civ/1947/1.html]

A famous exigesis on the meaning, in law, of the word "reasonable".

Lord Greene MR had this to say:

For instance, a person entrusted with a discretion must, so to speak, direct himself properly in law. He must call his own attention to the matters which he is bound to consider. He must exclude from his consideration matters which are irrelevant to what he has to consider. If he does not obey those rules, he may truly be said, and often is said, to be acting “unreasonably.” Similarly, there may be something so absurd that no sensible person could ever dream that it lay within the powers of the authority. Warrington L.J. in Short v. Poole Corporation [1926] Ch 66, 90, 91 gave the example of the red-haired teacher, dismissed because she had red hair. That is unreasonable in one sense. In another sense it is taking into consideration extraneous matters. It is so unreasonable that it might almost be described as being done in bad faith; and, in fact, all these things run into one another.

[...]

That, I think, is quite right; but to prove a case of that kind would require something overwhelming, and, in this case, the facts do not come anywhere near anything of that kind. I think Mr. Gallop in the end agreed that his proposition that the decision of the local authority can be upset if it is proved to be unreasonable, really meant that it must be proved to be unreasonable in the sense that the court considers it to be a decision that no reasonable body could have come to. It is not what the court considers unreasonable, a different thing altogether. If it is what the court considers unreasonable, the court may very well have different views to that of a local authority on matters of high public policy of this kind. Some courts might think that no children ought to be admitted on Sundays at all, some courts might think the reverse, and all over the country I have no doubt on a thing of that sort honest and sincere people hold different views. The effect of the legislation is not to set up the court as an arbiter of the correctness of one view over another. It is the local authority that are set in that position and, provided they act, as they have acted, within the four corners of their jurisdiction, this court, in my opinion, cannot interfere.