[DavidI]

Take a photo of the car and report it anonymously. Give the police the license plate, make and model. It made be a stolen car that was dumped. In many cases, the bad guys change the license plates stolen from another car called "cold plating." Either way, in California a member of law enforcement would come out, mark the tires and street with a date and give the owner 72 hours to move the vehicle. If after the 72 hours it has not been moved, it would be towed away.

Good luck, David