1995 TOYOTA 4RUNNER Power Train Problems

I BELIEVE, THOUGHT, SWEAR I SET MY 1995 TOYOTA 4RUNNER IN THE PARK POSITION. I RECEIVED A CALL FROM SECURITY INFORMING ME IT ROLLED AND HIT ANOTHER VEHICLE. I FOUND MY VEHICLE AND OBSERVED THAT THE SUV WAS NOT IN PARK, BUT THE DRIVE. HOW IS THIS POSSIBLE? I SHOULDN'T BE ABLE TO TAKE THE KEY OUT OF THE IGNITION WHILE THE LEVER IS IN THE DRIVE POSITION. ACCORDING TO THE MANUAL, "ON VEHICLES WITH AUTO TRANSMISSION, THE SELECTOR LEVER MUCH BE PUT IN THE "P" POSITION BEFORE TURNING THE KEY TO "LOCK" POSITION. "LOCK" - ENGINE IS OFF AND THE STEERING WHEEL IS LOCKED. THE KEY CAN BE REMOVED ONLY AT THIS POSITION." THIS IS NOT THE FIRST TIME I'VE BEEN ABLE TO TAKE THE KEY OUT OF THE IGNITION WHILE THE LEVER IS IN DRIVE POSITION. I MAKE A CONSCIOUS EFFORT TO MAKE SURE IT'S IN PARK BEFORE...