Wednesbury Unreasonableness and Irrational Administrative Decisions in Kenya

Administrative decisions often involve judgment, expertise and competing public interests. A court does not set aside a decision simply because another outcome could have been reached. Judicial review for irrationality asks a narrower legal question: whether the decision is so disconnected from the lawful purpose, information or reasons that it falls outside the range of decisions the decision-maker could properly make.

This ground is commonly called Wednesbury unreasonableness. In Kenya, it is applied through the statutory and constitutional framework for administrative action, with close attention to the decision’s legal purpose and the material available when it was made.

What does Wednesbury unreasonableness mean?

Wednesbury unreasonableness is a traditional judicial-review expression for a decision that is not merely debatable or harsh, but is legally irrational. The point is not that the court would have balanced the factors differently. It is that the result, or the route to it, lacks the rational foundation required by law.

The threshold protects both accountability and institutional roles. Public bodies must explain and exercise power lawfully, but courts should not convert judicial review into a general appeal on policy, technical expertise or factual preference. A claimant alleging irrationality should therefore identify the decision, its statutory purpose, the relevant evidence and the specific disconnect said to make the decision unreasonable.

Reasonableness is tested in context

Article 47 of the Constitution of Kenya places reasonableness within the law of administrative action. In an irrationality challenge, however, the useful work is done by comparing the decision with the function the decision-maker was required to perform—not by reciting the constitutional standard in the abstract.

Context determines the weight of that comparison. The seriousness of the consequence, the statutory objective, the information available, the quality of the reasons and the kind of expertise involved can all matter. A review court tests whether the reasoning has a lawful foundation; it does not retake the administrative choice simply because a different balance was possible.

Look for a rational connection

Section 7(2)(i) of the Fair Administrative Action Act, 2015 permits review where an administrative action or decision is not rationally connected to its purpose, the purpose of the empowering provision, the information before the administrator or the reasons given. The provision directs attention to the link between a decision and its legal and factual basis.

For example, a decision may be vulnerable if it purports to advance a statutory objective while relying on information that does not address that objective, ignores a central factor the law requires to be considered, or gives reasons that do not support the outcome. The issue is the material connection, not whether every detail of an administrator’s reasoning could have been expressed better.

A clear chain from the legal purpose, through the material considered, to the conclusion reached is ordinarily the most reliable indicator that the decision has a rational foundation.

Reasons allow fairness and legality to be tested

Reasons are often essential to a meaningful challenge. Article 47(2) gives a person whose rights or fundamental freedoms are likely to be adversely affected by administrative action a right to written reasons. Section 6 of the Act allows a person materially or adversely affected to request the information necessary for an appeal or review, including reasons and relevant documents. The administrator must ordinarily provide written reasons within 30 days of the request.

If reasons are not supplied, section 6 creates a presumption, in review proceedings and absent proof to the contrary, that the decision was taken without good reason. That does not make every failure to provide a perfect explanation decisive. The Act recognises that departure from the requirement may be reasonable and justifiable in the circumstances. Still, a decision-maker should record and communicate the basis of a significant adverse decision; an affected person should request the reasons and preserve the response.

What irrationality is not

Irrationality is not a shortcut for relitigating disputed facts, replacing specialist judgment or avoiding a statutory appeal. A regulator may choose between lawful options; a tribunal may assess evidence; and an administrator may make a decision that disadvantages one party without acting irrationally. The relevant question is whether the power was exercised within the bounds of rationality, legality and fairness set by the applicable law.

That distinction is especially important where the real complaint is that a factual finding is wrong or a technical assessment should have been given different weight. The immediate question then is not whether the result is unpopular, but whether the stated path from evidence to outcome is materially incoherent. Disputed evidence or technical judgment may need a forum equipped to hear and test it.

Practical steps after an apparently irrational decision

• Read the enabling law and identify the decision’s lawful purpose and relevant criteria.
• Obtain the notice, reasons, hearing record, documents relied on and any internal-review information.
• Identify the alleged disconnect: purpose, evidence, mandatory factor, reasons or legal power.
• Check whether an internal review or statutory appeal is available and whether it must be used first.
• Act promptly; preserve the complete record before seeking legal advice on forum and remedy.

An irrationality challenge is strongest when it demonstrates a material gap between a decision and the legal basis that should support it. Clear reasons and a complete record make it possible to distinguish a genuinely unlawful decision from one that is simply contested. They also allow the decision-maker to identify and correct a genuine defect before litigation becomes necessary in practice. This disciplined comparison keeps the challenge focused on legal rationale rather than hindsight or preference.