AFTER DRIVER STEPPED OUT OF VEHICLE, THE GEAR SHIFT JUMPED FROM PARK INTO REVERSE. VEHICLE THEN HIT AN EMBANKMENT, WHILE TRAVELING BACKWARDS, JUMPED INTO DRIVE AND RAN OVER DRIVER, SEVERELY INJURING DRIVER. NEITHER LINCOLN DEALERSHIP NOR A FORD DESIGN ANALYSIS ENGINEER WERE ABLE TO FIND A CAUSE FOR THIS ERRATIC OCCURRANCE.