The objective of the present study was to develop the diagnostic criteria for determining the positions of the participants of a road traffic accident inside the passenger car compartment based on the analysis of the characteristic features of vertebral lesions in the victims. The archival documents of forensic medical expertises were used to analyze the specific characteristics of fractured cervical vertebra in the victims of the accident inside the passenger car compartments including the drivers (n=92), the occupants of the forward (n=43) and rear (n=37) seats of the car. Localization and mechanisms behind the formation of vertebral lesions in the cervical part of the spinal column associated with the intra-compartment injury is of primary importance for the diagnostic purposes. The character of an injury to the cervical region gives evidence of the position of the driver and the occupants of the car inside the passenger compartment at the moment of the accident. Injuries to the cervical, thoracic, and/or sacral vertebrae may be indicative of the seat (either driver's, forward or rear) occupied by the victim(s). The fractures of the sacral part of the vertebral column are of negligible value for the differential diagnostics between the positions of the driver and/or other victims because they equally frequently occur in the drivers and occupants of both the forward and rear seats. Nevertheless, the proposed criteria made it possible to construct the mathematical model in the form of the logistic regression equations and to use them for making the probabilistic predictions as regards the positions of the participants of a road traffic accident inside the passenger car compartment based on the selected combination of pathomorphological characteristics in the victims.