Challenges arising from the application of standards сriminal procedural law as a result of the transition of territory from one state to another

Introduction: the paper considers some aspects of the challenges the application of standards criminal procedural law as a result of the transition of territory from one state to another. The topic is is very urgent as the number of cases of change of jurisdictional status of territories arose on grounds of independent state (for example, Catalonia) or transition of territory from one state to another (for example, Crimea) Materials and Methods: descriptive, scientific-analytical, historic and legal, theoretical and legal methods, analysis and synthesis were used in the framework of comparative analysis. In the course of the study, the materials of published judicial practice were summarized. Generalization of the published cases was held. Besides, the author carried out interview of police officers of Crimea, particularly employees of the prosecutor's office and members of the economic security units and anti-corruption departments of internal affairs bodies within the research. Results: in the course of the scientific research, the problems, encountered in the activity of law enforcement bodies, were revealed, and the application of the norms of the criminal procedural law in the course of changing the jurisdiction of the territories. These problems can affect the legal status of law enforcement agencies, and the activities to investigate, review and resolve criminal cases. Discussion and Conclusion: when applying norms of criminal procedural law, the subject should be guided by the current criminal procedure law. However, when the jurisdiction of territories changes, the criminal procedural law, which is subject to application, also changes. It should be remembered that, within the framework of international human rights standards, there are general principles of criminal prosecution, such as the principle of the presumption of innocence, the principle of the administration of justice only by the court, the principle of impossibility of "turning to the worst", etc. All these principles should be respected and maintained regardless of changes in jurisdiction of different territories. Identification and solution of the problems identified will help to increase the effectiveness of activities to bring individuals to criminal responsibility and the effectiveness of the implementation of the principle of the inevitability of criminal responsibility for the crime committed while changing the legal status of the territory.