In the words of the Thunderbird Tribunal, „the term `legitimate expectations` refers to … a situation in which the conduct of a Party creates reasonable and reasonable expectations on the part of an investor (or investment) to act on the basis of that conduct, so that a failure by [the State] to meet those expectations could result in harm to the investor (or investment). 1 The legitimacy of an expectation can therefore be derived only if it is based on the sanction of law or custom or on a defined procedure applied in a regular and natural system. Although the GCHQ case states that „effect is given in public law“ for a legitimate trust, the legitimacy of a trust is not conceived as a conclusive label that ensures the provision of recourse by the court, but rather justifies protection of appearance. It can be refuted by a suppression of public interests.  „may divert attention from the question itself, namely what is necessary to ensure that the decision is made fairly in the circumstances in which the decision is to be made, given the legal framework within which the decision is to be made.“ The right of trust has been one of the most interesting areas of the development of judicial review law in recent years. It departs from the more traditional grounds for challenging the decisions of public authorities, such as procedural violations and misconduct. The first arbitral awards directly related to legitimate expectations were as follows: Therefore, it can be said that this doctrine is a form of control of the administrative authority. Where representation has been made, the doctrine of the protection of legitimate expectations essentially imposes on the authority the obligation to act fairly, taking into account all the relevant factors relating to such a legitimate expectation.2 It also adds to the authority the obligation not to act in a way that circumvents legitimate expectations without having any reason of public policy; to justify this.3 In addition to its application in the United Kingdom, the procedural relationship of trust was established by the Federal Court of Australia in GTE (Australia) Pty. Ltd.c. Brown (1986).
 In this case, the Minister of State for Administrative Services, acting on behalf of the Minister of State for Industry and Trade, imposed anti-dumping duty on the applicant. The applicant brought an action, arguing that the authorities had denied her natural justice by failing to respect it, by not respecting it, in order to give a hearing towards the end of the investigation into whether the duties should be collected and by derogating from certain procedures. Applying Ng Yuen Shiu and the GCHQ case, the court agreed that the plaintiff`s legitimate expectations had been disappointed by the lack of a hearing and that it had been unfair for the authorities not to comply with the procedures.  It is a principle of administrative law that public decision-makers should be required to meet the legitimate expectations they create. If a decision-maker has not met a legitimate expectation in the decision-making process, the decision may be challenged. Expectation cannot be the same as anticipation. It is different from a wish, wish or hope and does not constitute a claim or claim based on a right. As serious and sincere as a wish, desire or hope may be, and as confident as one can turn to them to satisfy them, they alone cannot constitute enforceable expectations, and mere disappointment has no legal consequences. A pious hope, which itself leads to a moral obligation, cannot constitute a legitimate expectation.10 Courts consider not only the relevance of the expectation, but also other considerations, such as the manner in which it is presented. In GCHQ, Lord Diplock noted that a lawful trust is a trust that „has consequences that have consequences in public law, while an expectation or hope that a benefit or advantage will continue to be appreciated, while it may very well be maintained by a `reasonable` man, would not necessarily have such consequences.“  This is a question of law that must be decided on an objective basis with full reference to the facts.  However, in the case of united policyholders, the government of Trinidad and Tobago had never accepted that a promise of support made to policyholders of a large insurance company in the aftermath of the global financial crisis raised legitimate legal expectations. Nevertheless, the Privy Council concluded that it was entitled to withdraw any guarantees that might have been given.
To ask a public body to meet a legitimate expectation, the court issues a mandatory order (also known as mandamus). It is a prerogative that directs a public body to perform a public duty and is often used to force public bodies to exercise the powers conferred on them.  When considering a right to the protection of a legitimate expectation against the decision of a public authority, courts deliberate on three essential considerations: A procedural relationship of trust arises when an authority agrees that it will follow a particular procedure before making a decision on the merits of a particular case. Examples of procedural trusts are trust in consultation and a fair trial.  There is a legitimate expectation on the basis of reasons when an authority makes a statement of the final decision and the outcome it will take in a particular case.  The Court`s case-law has developed the doctrine of the protection of legitimate expectations in Bangladesh since 1987 […].