PARK TO REVERSE: VEHICLE TRANSMISSION SELF ENGAGED FROM PARK TO REVERSE. MECHANICAL DEFECT, AS A RESULT, THE SHIFT CONTROL LEVER COULD DISENGAGE FROM THE TRANSMISSION WITHOUT WARNING. ON WED. 12/20/17 AT 3:10 P.M. ' I WAS LEAVING WORK I ENTERED MY 2013 FORD ESCAPE & STARTED THE VEHICLE WITH FOOT ON BRAKE. NOTICED MY FRONT AND BACK WINDOWS WERE COVERED WITH SNOW. ENGAGED THE WINDSHIELD WIPER ON FRONT WINDOW, & REALIZED THAT THE SNOW WAS ACTUALLY FROZEN ICE THAT NEEDED TO BE SCRAPED. VEHICLE WAS IN PARK POSITION, LET UP ON THE BRAKE AND THERE WAS NO MOVEMENT OF THE VEHICLE. SCRAPER IN HAND, GOT OUT OF THE VEHICLE TO SCRAPE THE FRONT WINDSHIELD. WHEN EXITING THE VEHICLE, THE VEHICLE WAS STILL IN PARK POSITION/MOTIONLESS. THE VEHICLE WAS MOTIONLESS FROM THE TIME I EXITED THE VEHICLE TO THE TIME I MOVED TO SIDE OF CAR ON DRIVER SIDE, TO SCRAPE THE FRONT WINDSHIELD WITH SCRAPER. I STARTED TO SCRAPE MY FRONT WINDSHIELD. AFTER 3-4 SCRAPES ON THE FRONT WINDSHIELD, I NOTICED THAT THE VEHICLE STARTING TO MOVE IN THE REVERSE DIRECTION WHICH WAS AWAY FROM WHERE I WAS STANDING. I TRIED TO OPEN THE DOOR & GET INTO VEHICLE TO APPLY THE BRAKE, HOWEVER, THE DOOR MOMENTUM KNOCKED ME TO THE GROUND & I WAS DRAGGED BY THE DOOR OF THE VEHICLE AS THE VEHICLE WAS MOVING IN THE REVERSE DIRECTION. I WAS LOOKING AT THE FRONT WHEEL AS I WAS BEING DRAGGED UNTIL THE CAR TURNED ENOUGH TO RELEASE ME FROM THE DRIVER SIDE DOOR. THE VEHICLE STOPPED WHEN ITS BACK BUMPER HIT THE VEHICLE FRONT BUM