Legitimate Expectation: When a Promise to Consult Creates a Legal Duty

Public bodies sometimes promise to consult. Sometimes they have always consulted in the past. Does either of those facts create a legal obligation to consult again? The doctrine of legitimate expectation says it can, but the courts set the bar high, and the gap between what practitioners assume will count and what actually does is where most of the trouble starts.

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When does a duty to consult arise without a statute?

Most consultation duties are statutory. The Town and Country Planning Act, the NHS Act 2006, the Procurement Act 2023 and dozens of other instruments tell public bodies when and how they must consult. Where a statute is silent, however, a common law duty to consult can still arise, and the mechanism is legitimate expectation.

The High Court in R (Plantagenet Alliance) v Secretary of State for Justice [2014], the case about reburying Richard III, identified four circumstances in which a duty to consult may exist: statutory requirement, an express or implied promise, an established practice of consultation, or exceptional unfairness to an identifiable group if no consultation takes place. The first is straightforward. The second and third are where public bodies most often find themselves in difficulty, usually because they did not realise their own words or habits had created an obligation they would later be held to.

How clear does a promise need to be?

Very clear. The judicial test, confirmed by the Court of Appeal in R (MP) v Secretary of State for Health and Social Care [2020], is that the promise must be “clear, unambiguous and devoid of relevant qualification.” That formulation comes from Bingham LJ in R v IRC, ex p MFK Underwriting Agents [1990], and it has become the benchmark for every procedural legitimate expectation claim since.

The last three words of that test deserve attention. “Devoid of relevant qualification” means that a hedged commitment is not a commitment at all. A strategy document that says “we will consult on changes to the scheme, including the Inquiry’s recommendation” is making a promise. One that says “we may seek views on options for reform” is not. The gap between those two formulations is a single auxiliary verb. It is also the gap between a lawful decision and a quashed one.

R (Mitchell) v Secretary of State for Justice [2021] shows what happens when the promise is clear enough. The Government’s Victims Strategy, published in 2018, stated that it would consult on revising the unspent convictions rule in the Criminal Injuries Compensation Scheme following a recommendation by the Independent Inquiry into Child Sexual Abuse. The Government then ran a broader consultation on the Scheme but never asked about that rule. Lang J held that the Strategy’s language amounted to a procedural legitimate expectation. The court ordered a fresh consultation. The Government had said it would consult. It did not. That was enough.

Compare R (Possible (10:10 Foundation)) v Secretary of State for Transport [2024], where the same judge reached the opposite conclusion. Environmental groups argued that previous consultations on aviation decarbonisation should have created an expectation of further consultation on demand management. Lang J found no consistent practice and no unequivocal promise. The earlier exercises had covered different questions at different times and on different terms. Past engagement on broadly related topics, however extensive, was not enough to bind the Government to consult on a different question years later.

Does past practice carry the same weight as an express promise?

It can, but the threshold is higher. The Court of Appeal in MP held that a past practice of consultation must have been “so settled, uniform and unequivocal” that departing from it would be an abuse of power. Brooke Energy Ltd v Secretary of State for BEIS [2018] tested that standard. Renewable energy firms argued that changes to subsidy schemes should have been consulted on because previous subsidy changes had been. The court disagreed. The earlier consultations were infrequent, they covered distinct policy questions, and they did not amount to anything approaching a uniform practice.

The pattern across these cases is consistent. One or two consultations on related matters do not bind a public body to consult on every future change in the same territory. The practice must be regular, it must cover the same type of decision, and it must be conducted in a way that would lead a reasonable person to assume it would happen again. Anything short of that, and the claim fails.

What should practitioners take from this?

Two things, and they pull in opposite directions.

For those who draft policy documents, consultation strategies, and statements of community involvement: the courts will read your published commitments as a reasonable member of the public would read them, not as you might wish you had worded them after a judicial review claim lands on your desk. If a strategy says “we will consult,” that is a promise. If you do not intend to be bound by it, do not write it. And if you have already written it, assume someone has read it and is relying on it.

For those on the other side, who believe they are owed a consultation because one happened before: the bar is genuinely high. Isolated previous consultations, general statements of willingness to listen, and broad commitments to engagement are unlikely to meet the judicial test. The expectation must be grounded in something specific and unqualified. If it is not, the claim will fail regardless of how unfair the outcome feels.

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How tCI Can Help

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