CSS WHICH WAS INSTALLED BY AN OFFICER IN THE MIDDLE REAR SEAT AND RESTRAINED BY REAR LAP SEATBELT. WHILE DRIVING MADE A SUDDEN STOP, AND CSS WHICH WAS RESTRAINT BY THE MIDDLE REAR LAP BELT RELEASED, CAUSING THE CSS TO FLY OUT AND HIT THE DRIVER'S HEADREST. CHILD SUSTAINED INJURIES. PLEASE PROVIDE FURTHER INFORMATION.*AK