An aggrieved person is entitled to judicial review if he can show that a decision of the public authority deprives him of some benefit or advantage which in the past he had been permitted to enjoy and which he legitimately expected to be permitted to continue to enjoy until he was given reasons for withdrawal and the opportunity to comment on such reasons [See, (1992) 4 SCC 477]. The mere legitimate expectation of a citizen may not by itself be a distinct enforceable right but failure to consider and give due weight to it may render the decision arbitrary, and this is how the requirement of due consideration of a legitimate expectation forms part of the principle of non-arbitrariness, a necessary concomitant of the rule of law [See, (1993) 1 SCC 71]. A legitimate expectation is not the same thing as anticipation, though. It is distinct and different from a desire and hope. A legitimacy of expectation can be inferred only if it is founded on the sanction of law or custom or an established procedure followed in regular and natural sequence [See, 1999 3 SCC 499].
Recently, in P. Suseela v. University Grants Commission, (2015) 8 SCC 129 Hon’ble Justice R.F. Nariman, while explaining the Doctrine of Legitimate Expectation, has laid down in his usual inimitable style that “a legitimate expectation must always yield to the larger public interest.” It is perhaps surprising that when Courts have considered the issue of whether a public authority may lawfully resile from a legitimate expectation that consideration has been either brief or it has been obiter. The “must always” observation of Justice Nariman is an instance of stretching it too far. In borrowed words, “the law has long recognized differences between procedural and substantive legitimate expectations (See,  QB 213). Though the question of when a public authority may resile from a procedural legitimate expectation on grounds of public interest factors has not attracted a great deal of attention, the issue of when a public authority is entitled to resile from a substantive legitimate expectation is more controversial.“