The Coherence of the Doctrine of Legitimate Expectations

The doctrine of legitimate expectations is a developing area of administrative law, and many issues remain outstanding. Promises, practices, and policies generate legitimate expectations, but what is special about them? Why do they and only they generate legitimate expectations? The lack of an obvious answer has led some commentators to claim that the doctrine is ultimately incoherent and should be disaggregated. In this paper, we challenge this claim by arguing, first, that promises, practices, and policies each comprise or make applicable a certain type of rule, and second, that having a legitimate expectation is a matter of such a rule binding a public body to act in some way. This rule-based account gives the doctrine of legitimate expectations both coherence and distinctiveness.