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Five Grounds for Judicial Review

Judicial review stands as a cornerstone of administrative law, providing a mechanism through which the decisions of public bodies can be challenged in court. This process ensures that such decisions are made legally, fairly, and reasonably. While the grounds for judicial review have evolved over time, they broadly encompass illegality, irrationality, procedural impropriety, and, in some contexts, proportionality. This article delves into these grounds, elucidating their significance and application in judicial review.

Principle of Illegality

Illegality refers to situations where a public authority has acted outside the scope of its powers (ultra vires). This ground ensures that any decision, action, or failure to act is founded upon a proper legal basis and adheres to the law. Illegality may arise from a myriad of situations such as misinterpreting the law, failing to comply with statutory procedures, making decisions without the authority to do so, or exercising discretion for an improper purpose. The legal scrutiny under this ground ensures that public bodies do not overstep their legal boundaries, maintaining the rule of law.

Principle of Irrationality

Irrationality, often associated with the Wednesbury unreasonableness standard in the UK, challenges decisions that are so unreasonable that no reasonable authority would ever have come to them. This ground is inherently tied to the principle of reasonableness, serving as a check against arbitrary or absurd decisions. This ground is famously articulated in the Wednesbury unreasonableness test, derived from the case of Associated Provincial Picture Houses v Wednesbury Corporation [1948]. It sets a high threshold for challengers, as the courts are generally reluctant to substitute their judgment for that of the decision-maker.

Principle of Procedural Impropriety

Procedural impropriety targets the process by which a decision was made, rather than the decision itself. This ground encompasses failures to follow statutory procedures, breaches of natural justice, and failures to provide adequate reasons for a decision. Natural justice, with its twin pillars of the right to a fair hearing and the rule against bias, ensures that decisions are made in a fair and transparent manner. By enforcing procedural standards, this ground of judicial review upholds the principles of fairness and integrity in administrative processes.

Principle of Proportionality

Proportionality has gained prominence, especially in the context of human rights and European Union law. While not a standalone ground in all jurisdictions, it serves as an essential principle in evaluating whether the means used to achieve a legitimate aim are appropriate and necessary. The proportionality test typically involves assessing whether a decision is suitable to achieve its purpose, whether it is necessary, and whether the benefits outweigh the adverse impacts. This ground is particularly relevant in cases involving the balance between individual rights and public interests, offering a nuanced approach to judicial review that complements the traditional grounds.

Principle of Legitimate Expectation

The doctrine of legitimate expectation protects individuals from arbitrary changes in policy or promises made by public bodies. It arises when a public body's representations or conduct leads an individual to expect a certain outcome. This expectation can be procedural, such as the expectation of a fair hearing, or substantive, where the individual expects to benefit from a specific policy or practice. If a public authority fails to fulfil these expectations without a compelling justification, it may be grounds for judicial review.

Together, these grounds of judicial review form a comprehensive framework for challenging administrative decisions. They ensure that public bodies act within their legal limits, make decisions that are reasonable and fair, and respect the rights and freedoms of individuals. By providing a means to hold public authorities accountable, judicial review plays an indispensable role in upholding democracy, the rule of law, and good governance.

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