The Role of the Federal Court of Cassation in Protecting Constitutional Rights and Freedoms in Criminal Proceedings

Abstract

This study examines the impact of divergent national rules on the work of international investigation teams, focusing on the challenges arising from variations in legal systems regarding evidentiary, procedural, and substantive rules, and explores mechanisms to reconcile them to ensure effective international criminal justice. The study adopted a descriptive-analytical and comparative methodology, employing semi-structured interviews and content analysis on a purposive sample of thirty (30) legal experts and international investigators from five countries representing different legal systems and from the United Nations. The results revealed that differences in rules of evidence, particularly standards for the admissibility of evidence and confessions, constitute the greatest obstacle to international investigation teams, followed by procedural disparities concerning investigative confidentiality and defense rights. The findings also showed that the absence of prior legal coordination mechanisms further complicates international operations, while the European Joint Investigation Teams (JITs) model and the UN Office on Drugs and Crime (UNODC) have demonstrated success in overcoming these challenges through pre-established procedural agreements and standardized guiding tools. The study concluded that the optimal solution lies not in fully harmonizing national rules, but in developing flexible protocols that allow States to agree in advance on applicable rules while respecting internationally recognized minimum standards of defense rights.