Can I be held responsible for somebody else's actions even though I did not consent to the use of my car?

In California. I left my car in the street by accident on a street sweeping day and expected a lousy ticket when I got home from picking up distant automotive parts. Instead I received a phone call that my car was involved in an accident. I did not authorize anybody to move my car nor did I tell anybody where I placed the spare keys. My mother says she let a neighbor move my car to the next block after digging around for my spare keys. Then she said the neighbor left to retreived my car and returned with the news "I think I hit a car". The plaintiff's car had severe damage while I didn't have a single scratch on my property. Now I'm not sure of what happened that day. It was October of 2011. Are there any limitations as to how soon you must file charges? I still don't believe my car was even involved in the said accident because there was not a single scratch on the bumper.