This paper deals with the provisions on the judicial proceedings of medieval Serbia enacted in Dusan's Code. The aim of this paper is to provide an overview and analysis of the irrational and rational evidence of that period, as well as to point to the position of the defendant, bearing in mind this system of evidence. The judicial proceedings in Dusan's Code were predominantly organized in accordance with the rules of the indictment principle, however, what can also be observed is the onset of the understanding that the violation of certain norms is not only an issue of an individual. As a rule, the decision to initiate the judicial proceedings was dependant on the will of the injured party, and only exceptionally, in the event that the offense violated the public interest, the proceedings were initiated ex officio. In the sphere of evidence, it is possible to differentiate between irrational and rational evidence. The oath, the jury and the divine courts are considered to be the irrational evidence of this period. Among the rational evidence in Serbian medieval law, there is mention of 'obličenije' (capture of the offender in the act); 'svod', which the defendant used to prove that he did not steal the object of the crime, but that he came into possession of said object through someone else; including witnesses, documents and confessions. The existence of rational evidence meant proof of the defendant's guilt, in which case the irrational evidence was not presented. It was the absence of rational evidence that led to the presentation of irrational evidence, which means that irrational evidence was subsidiary in relation to rational evidence. If the defendant's guilt was proven by rational evidence, the strength of this evidence could not be mitigated by any type of irrational evidence, therefore it was not possible to cumulatively apply rational and irrational evidence. Some of the provisions of Dusan's Code give rise to the division of social classes, which was their characteristic: different social classes used different evidence to justify the same criminal offense, and the type and severity of the imposed criminal sanction was dependant on the social class to which the defendant belonged. During the proceedings, the defendant took an oath, which, given the influence of religion on the lives of people at that time, could have influenced him to tell the truth during the proceedings. After the hearing, the defendant could not alter his original testimony, and during the proceedings he was obliged to adhere to the case in dispute and could not blame the injured party for another criminal offense.