The principle of the separation of powers is based on the idea that in any political society that has acquired statehood, there are three distinct functions, each carried out by a separate authority, and these functions have independent statuses. In this regard, this principle generally requires that the authority to make laws, the legislative branch, the authority to execute the laws, the executive branch, and the authority to resolve disputes arising from their implementation, the judicial branch, be entrusted to separate organs, ensuring their independence from each other. This principle was enshrined in the 1789 Declaration of the Rights of Man and of the Citizen, and it was emphasized that societies where the separation of powers is not upheld and the rights of citizens are not secured cannot be considered to have a constitution. Therefore, this principle has been elevated to the foundation of the state constitution.

Article 2 of our constitution states that the Republic of Turkey is a state governed by the rule of law. A state governed by the rule of law is one where actions and processes are in accordance with the law, based on human rights, aimed at protecting and strengthening these rights and freedoms, establishing a just legal order in every field, avoiding situations and attitudes contrary to the constitution, being bound by the superior rules of law, and open to judicial review. In countries that embrace the rule of law principle, the issue of supervising the actions and processes of the administration is always a possibility. As a requirement of the rule of law principle, it ensures that all actions and processes of the administration are subject to judicial review, which not only establishes the adherence of the executive branch to the law but also serves as the most effective safeguard of the fundamental rights and freedoms of individuals.

Those exercising public power must be bound by these rules from laws to other regulatory actions and even individual actions in their arrangements. This necessity compels the existence of a hierarchy of norms. The hierarchy of norms requires, among other things, that universally recognized legal principles, as well as constitutional provisions, laws, regulations, and bylaws, must be consistent, with each lower-level norm conforming to the higher-level norm. In this sense, a state governed by the rule of law is one where the hierarchical structure of legal norms that restrict public power is established. In this model, the validity condition of each rule is its conformity to the norm above it. Such a system obligates the presence of equality before the law and the existence of an independent judiciary against legal norms.

In this regard, two fundamental requirements are important for realizing the rule of law. Firstly, ensuring the protection of the rights and freedoms of individuals, which compels the supremacy of the law and justice, especially the constitution. Secondly, the regulation of state organs and functions in the use of power and the acceptance of the hierarchy of norms.

Like in all countries that embrace the administrative system, the public authorities in our country are endowed with the privilege of public power while using state powers. In the legal relations entered into by these public authorities with third parties, they are granted the authority to unilaterally produce legal consequences and effects, independently of the will of third parties, and even against their opposing will, often exerting such authority by force. Given these powers of public authorities, it is essential that the security of individuals in positive norms is assured, and that the actions of public authorities are subject to effective judicial review, which is considered as the main mission of a “law-abiding state.” The supervision of all actions and processes undertaken by the administration through the judiciary varies according to the legal rules in each country and is carried out by administrative judicial bodies, particularly in countries like ours that embrace the administrative system.

In administrative law, the authority of the administration to act unilaterally in legal relationships established with individuals, often in opposition to the will of the individual and even, when necessary, to forcibly establish a legal relationship, is explained by the public power it possesses. This unequal, privileged, and exclusive status based on public power is referred to as the privileges of public power. Similarly, in tax law, which involves frequent and effective interventions in many fundamental rights and freedoms such as the right to property and freedom of contract, in order to prevent arbitrariness, the rule of law principle in both tax regulations and their application by administrative and judicial authorities guarantees the protection of the fundamental rights and freedoms of individuals.

In light of this privileged status of public power, the most important guarantee of the legal security of third parties is the effective administrative adjudication in legal relationships established by the administration with third parties. Therefore, in the face of the privileges of public power possessed by the state and the administration, the establishment of the legal system in a way that is based on trust and stability is crucial, and the administrative judiciary, which will gradually conduct judicial review of the actions of the administration on behalf of individuals, plays a significant role here.

In the legal system of our country, which embraces the administrative system, the administrative judiciary is organized independently of the judicial system. In addition, our country adopts a comprehensive jurisdictional system in administrative judiciary. In countries with a narrow-jurisdiction administrative judiciary, cancellation cases are generally heard in administrative courts, while cases related to the financial liability of the administration are heard within the judicial system. In a comprehensive jurisdictional administrative judiciary system, as a rule, the legal control of actions and processes of the administration concerning public law is carried out in administrative courts, regardless of the type of the case.

The judicial review of the administration is one of the essential conditions of a state governed by the rule of law. The mere presence of the phrase “rule of law” in legal regulations does not make the system a state governed by the rule of law. Through the judicial review of the administration, administrative courts ensure that the administration acts in compliance with the law, secure the fundamental rights and freedoms against the unlawful actions and processes of the administration, maintain the legal order and stability, and create law through their precedents. Administrative judicial review not only protects individuals against the administration but also contributes to the protection of the objective (objective) legal order. Furthermore, the interpretation and application of legal rules are also expected from judicial review. On the other hand, administrative judicial authorities are subject to certain limits when conducting this review. Therefore, an administrative judicial authority cannot produce and apply a legal rule specific to the dispute before it. An administrative judicial authority should determine the applicable law for an administrative action or process. It should specify what the law is in its decision, how it should be understood, and how it should be interpreted. In addition, the judicial authority that has a view that an action is contrary to the law should indicate which legal rule the action violates in its decision.