
An expert in criminal proceedings is an assistant to the trial authority. It provides special evidentiary information and assists the procedural authority conducting the proceedings at a given stage in resolving the case. In a small number of cases, the Code of Criminal Procedure indicates the specialty of experts to determine certain circumstances that require resolution in criminal proceedings. It defines procedural activities, the correct performance of which depends on the participation of an expert. The expert’s opinion is a special, self-contained source of evidence, and the special knowledge of this participant in the criminal proceedings is necessary for its issuance.
In the article, the author leaned into the issue of the categories of experts appearing in the criminal process. He discussed the position of court experts, ad hoc experts, as well as expert witnesses and expert consultants. The paper also focused on the issue of the procedural standing of a scientific institution and a specialized institution. A significant part of the study is a consideration of the procedural position of private experts.