The Evidence Admissibility Test in Criminal Proceedings: Concept, Case Law of the Supreme Court, and Canadian Experience

Abstract

The article examines the development of the evidence admissibility test in Ukrainian criminal proceedings. It is established that neither criminal procedural law nor case law currently provides a unified admissibility test, understood as a coherent algorithm that a judge could consistently apply to any contested item of evidence. The Supreme Court has repeatedly moved towards developing such a test. However, it has proceeded by formulating individual propositions, conclusions and legal positions that supplement and develop its previous findings. Consequently, the complete model must be reconstructed from a mosaic of judgments delivered by different chambers over the years. The purpose of the article is to define the concept and structure of the evidence admissibility test by systematising doctrinal approaches, conducting a chronological analysis of the Supreme Court’s case law and comparing the Ukrainian approach with Canadian experience, where such a test has been developed at the constitutional level. The study employs general scientific and specialised legal methods, primarily the dogmatic, comparative legal and historical legal methods. It is demonstrated that Ukrainian case law has consistently rejected the categorical concept of the “merciless exclusion” of evidence and has evolved from formal procedural criteria, including the proper source, subject, procedure for obtaining evidence and manner of its documentation, towards a substantive approach. Under this approach, the decisive considerations are the impact of the violation on human rights, the reliability of the evidence and the fairness of the proceedings as a whole. The article reconstructs the multi-level structure of the admissibility test, encompassing a formal procedural review, an assessment of whether the human rights violation was substantial, an examination of derivative evidence under the “fruit of the poisonous tree” doctrine, the related concepts of asymmetry, bad-faith error and the “broken mirror”, as well as the procedural rules governing decisions on the inadmissibility of evidence. The conceptual affinity between the Ukrainian substantive approach and the three-part test formulated by the Supreme Court of Canada is demonstrated. The expediency of the selective reception of the Canadian model of structured balancing is substantiated, provided that the distinction in Ukrainian law between the general rule and the special regime applicable to substantial violations is preserved. Proposals are formulated for the generalisation of judicial practice and the improvement of criminal procedural legislation.