Improper Purpose and Colourable Exercise of Power

In one line

A power given for one purpose and used for another is void, and nobody has to be dishonest for that to be true.

In the wording a student can write in an exam: improper purpose, also called the doctrine of extraneous purpose or detournement de pouvoir, means the use of a statutory power for an object other than that for which it was conferred; a colourable exercise of power is the use of a power which is apparently within the authority's competence but which in substance achieves something the authority could not do directly.

Why this is the most useful ground in the group

Because it does the work of mala fides without the burden of proving dishonesty. A court which will not say that an officer acted corruptly will readily say that a power to acquire land for a public purpose was used to acquire a particular man's land because of a dispute with him. The finding is about the object, not about the state of mind.

How the purpose is found

From the statute. The preamble, the long title, the scheme and the section itself. This is Lord Reid's method in Padfield v. Minister of Agriculture, Fisheries and Food, [1968] AC 997: the policy and objects of the Act are found by construing the Act as a whole, and construction is a matter of law for the court.

From the order and the file. The reason recorded, the note sheet, the sequence of events.

From the effect. Where the effect of the order is to achieve something the Act does not contemplate, and no other explanation is offered.

Mixed purposes

An order is often made for two purposes, one proper and one not. The courts have used several tests, and the one most often applied is the dominant purpose test: if the improper purpose was the dominant one, or if the order would not have been made but for it, the order falls. Where the proper purpose alone would have produced the same order, it stands.

Colourable exercise

The phrase means that the power is exercised in a form which appears lawful but which in substance is a device. The doctrine is expressed in the maxim that what cannot be done directly cannot be done indirectly. In Gullapalli Nageswara Rao v. Andhra Pradesh State Road Transport Corporation, AIR 1959 SC 308, the Court considered the argument of colourable legislation and said that the question is in substance one of legislative competence, and that a legislature cannot overstep the field of its competence directly or indirectly; while if it has the power to make the law, its motive in making it is irrelevant.

That last sentence is the key distinction for an answer: motive is irrelevant to legislation but relevant to administration, because an administrative power has a stated purpose and a legislative power does not.