Scope of application as a criterion for classifying the principles of civil procedural law

The subject of the research is one of the key problems in the theory of principles of civil procedural law – the problem of their classification. The novelty of the study lies in the fact that the classification of principles by scope of action is considered through the prism of justifying civil procedural law as an independent branch, which includes three sub-branches: civil procedural law, arbitration procedural law, and administrative procedural law. The research focuses on the works of scholars in the field of civil procedure dedicated to the theory of principles of civil procedural law, as well as the norms of procedural (civil, arbitration, and administrative) legislation, through which the principles of civil procedural law are directly and indirectly enshrined. Special attention is paid to analyzing the state of procedural doctrine regarding principles that express the legal uniqueness of the branch of civil procedural law, principles that determine the specifics of individual institutions of this branch, as well as the correlation of these principles with each other. The methodological framework of the research consists of the following methods: analysis, synthesis, systemic-structural, formal-logical, theoretical-forecasting, comparative-legal, interpretation of legal norms. The main conclusions drawn from the research are as follows. The scope of action retains its significance as a central criterion for classifying principles, through which the principles expressing the specificity of the subject of regulation, such as civil procedure, are brought into a legally and logically coherent system. From the perspective of the identification function of principles, the scope of action, as a classification criterion, has three aspects (forms of expression): 1) procedural law as a collection of two fundamentally different in legal nature procedural branches (criminal procedural law and civil procedural law); 2) civil procedural law as a kind of mega-branch, the subject of regulation of which is the administration of justice in civil matters in the broadest sense (civil, administrative, and economic dispute cases), that is, civil procedure; 3) the institution of civil procedural law.