Mandatory Nature of Lawful Prosecutor’s Assignments and Instructions in Pre-Trial Investigation: Limits of the Investigator’s Procedural Independence and Their Significance for Criminal Procedural Proof

Abstract

The relevance of the study is determined by the need to ensure an appropriate balance between prosecutorial procedural guidance and the investigator’s independence as a holder of criminal procedural competence established by law, as well as by the increased procedural significance of written assignments and instructions issued by a prosecutor, non-compliance with which may have direct consequences for the investigator’s further participation in a particular pre-trial investigation. This issue becomes particularly important where a prosecutor’s assignment or instruction concerns the conduct of investigative (search) actions, covert investigative (search) actions, or other procedural actions whose results are used in criminal procedural proof.
The purpose of the article is to examine the legal nature and limits of the mandatory nature of lawful written assignments and instructions issued by a prosecutor during pre-trial investigation, to determine their correlation with the investigator’s procedural independence, as well as to clarify the legal consequences of their non-execution or improper execution and the significance of the relevant procedural violations for criminal procedural proof.
It is substantiated that the mandatory nature of a prosecutor’s assignment or instruction is determined by its lawfulness, which encompasses the proper authority of the issuing subject, the limits of criminal procedural competence, the lawfulness of its content, and compliance with the required written form.
It is established that the investigator’s procedural independence does not exclude the binding nature of lawful written requirements issued by the prosecutor; however, their execution may neither alter the scope of the investigator’s competence established by law, substitute the required judicial control, nor justify a violation of procedural form.
The article demonstrates the difference in the legal significance of a written assignment for an investigator and for an officer of an operational unit, as well as the specific features of the binding nature of assignments and instructions within the model of procedural interaction between the National Anti-Corruption Bureau of Ukraine and the Specialized Anti-Corruption Prosecutor’s Office.
It is concluded that a violation related to the issuance and execution of a prosecutor’s assignments and instructions acquires evidentiary significance not merely by virtue of its occurrence, but only where it directly affects the competence of the relevant subject, the procedure for conducting a procedural action established by law, or criminal procedural safeguards on which the lawful formation of a specific item of evidence depends.