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This study presents the case law of the Polish Constitutional Tribunal referring to the ne bis in idem principle and the case law of the European Court of Human Rights issued on the basis of Article 4 of Protocol No. 7 to the European Convention on Human Rights. The work also includes the discussion of solutions adopted in Polish law in the case when a person meets both the signs of a crime/offense and the premises of administrative responsibility of a punitive (repressive) nature in a single unlawful act. For many years, a system-wide solution to this type of convergence was missing in Polish law. The situation changed last year with the introduction of Article 189f to the Code of Administrative Procedure. However, as indicated in the study, this provision does not fully implement the ne bis in idem standard developed by the European Court of Human Rights.