The vehicle was placed in park with the engine running. No one was in the vehicle when, on it's own, it came out of park and rolled down our driveway, coming to a stop after hitting a tree. A person or cat could have easily been on the driveway and run and killed. It subsequently cost $10751.42 to repair the damage to the rear tailgate. No previous issues had been noted prior to this incident. This occurred in July 2001 and was submitted to our insurance company where we paid a$1000 deductible and caused our rates to go up. We have contacted Ford without any success.