The Institute of Forensic Engineering, in cooperation with Dipl. Ing. Michael Weyde, PhD., has carried out series of crash-tests focused on analysis of relative motion of MPV vehicle and two types of dummy’s with full coverage. Dependence of marginal conditions (coefficient of friction vehicle – dummy, coefficient of restitution) on the impact speed has been determined by processing of individual tests (with the speed of vehicle´s impact into pedestrian ranging from 21 up to 73 km/h). The pattern of dependence of both magnitudes is similar for USI dummy and BD dummy where increase in the impact speed causes decrease in coefficient of restitution and increase in coefficient of friction vehicle – dummy. The article is dealing also with the issue of dummy´s or human body´s sliding phase after collision (mean value of dummy´s and human body´s deceleration since the moment of the first contact with the road until stopping in the final position), issue of dragging the dummy by vehicle´s movement after collision and causes of dependence of marginal conditions (coefficient of friction vehicle – dummy, coefficient of restitution) on the impact speed.