Employing systematic document analysis and other methods, this article analyses a long-standing and still relevant issue related to the interpretation and application of the law regulating relationships in the field of European Union criminal justice within the framework of the national criminal proceedings that are taking place in EU member states. The article places special emphasis on the explanation and application of the principle of mutual recognition within the framework of one of the newest instruments of international cooperation in the European Union criminal proceedings meant to prevent conflicts of exercise of jurisdiction and to solve issues arising between two or more member states. The analysis of conflicts of exercise of jurisdiction provided in this paper is not limited to a mere explanation of the concept as such, but includes an essential analysis of other related issues,
such as the principle of mutual recognition, its influence on the recognition of criminal proceedings as parallel proceedings, and including other aspects related to the matching of the form of national criminal proceedings with the criminal proceedings taking place in another member state. Finally, significant attention is given to one of the objectives in terms of prevention and solution of conflicts of exercise of jurisdiction, namely, the ne bis in idem principle and its application in case of parallel criminal proceedings taking place in two or more member states. One of the key conclusions offered here is that in order to eliminate conflicts of exercise of jurisdiction, positive law in the process of conflicts of jurisdiction must become an effective measure in criminal justice; however, only on the condition that at least a minimum likelihood in the form of criminal proceedings adopted by different EU members states is ensured as a precondition necessary to enable a smooth application of the principle of mutual recognition