On the basis of regulatory and doctrinal sources the authors consider the issue about which procedural subject possesses the status of an investigator in the states of the former USSR. The authors prove that the problems that are facing the CIS and the Baltic states in the sphere of organizing pre-trial proceedings, in particular, that of institutional affiliation of an investigator, are inherited from the Soviet time, since it was during this period that investigation ceased to be judicial. It is justified that the majority of the CIS countries have preserved the model of organizing pre-trial proceedings that existed in the Soviet times; and only four countries – Kazakhstan, Russia, Belarus and Ukraine attempted to create a body authorized exclusively for the conduct of preliminary investigation. It is justified that due to this fact it is impossible to consider the creation of investigative committees in the former USSR states as a universal trend. The authors demonstrate that some countries from this group have created investigative committees while others have not. At the same time in none of the legal orders preliminary investigation has become judicial.