The "fruit of the poisonous tree" doctrine in the administrative proceedings

Abstract

The study examined the possibility of applying the "fruit of the poisonous tree" doctrine in Ukrainian administrative proceedings in the absence of its direct codification in the Code of Administrative Proce­dure of Ukraine. The relevance of the topic is deter­mined by the fact that in public-law disputes, it is often the defect of the initial administrative action (lack of competence, procedural violations, unlawful basis for intervention) that gives rise to a "chain" of derivative evidence and decisions, which are subse­quently used by the authority to justify its position, and inconsistent approaches of courts to assessing such a chain reduce the predictability of law enforcement. The hypothesis of the study is the statement that the idea of derivative inadmissibility can be integrated into the administrative process as an evaluative principle of judicial control. In the event that a primary action is recognized as unlawful, the court must critically assess the admissibility and evidentiary value of the information obtained through this action, as well as the lawfulness of the acts based on it, taking into account the presence or absence of an independent legal basis for their obtaining or adoption. To test the hypothesis, a normative-dogmatic analysis of the rules of the Code of Administrative Procedure of Ukraine regarding evidence, their admissibility, and the active role of the court was used, as well as a comparison of these provisions with modern judicial practice of admi­nistrative courts and practice in cases of administrative offences, where the cause-and-effect logic of "derivativeness" can be traced. The research results show that the doctrine is effectively implemented through the establishment of primary illegality and the court’s refusal to rely on derivative materials; however, its application should be limited by the requirements of proportionality, the subject of proof, and the inadmissibility of excessive formalisation. The practical significance of the obtained conclusions lies in shaping guidelines for the partiesʼ argumen­tation and for motivating judicial decisions in disputes concerning derivative evidence and administrative acts. The feasibility of supplementing Part 1 of Article 74 of the Code of Administrative Procedure of Ukraine with a rule according to which the court does not take into account not only evidence obtained in violation of the law but also derivative evidence and information obtained on its basis has been justified.