What can you do if your son who does not live at home was involved in an auto accident with your car but the insurance company claims he is more than an occasional driver?

Basically the definition is as follows. Any person who has regular access to your vehicle would not be considered an occasional driver. If your son has insurance on his own vehicle then that coverage would follow him to a borrowed vehicle and there would be no need for this question. If he has no other auto or auto insurance and / or his drivers license reflects your home address, then obviously he is an authorized regular driver of your vehicle. Where the person lives, At home, not at home, does not determine his status as an occasional or regular driver. The question is does he have regular access to the vehicle in question whenever he needs or wants to drive. The best way to prove that he is an occasional driver would be to demonstrate that he owned his own vehicle at the time of the accident, that his vehicle was insured at the time. that the address on his drivers license reflects an address other than yours and that his vehicle was registered at his home address which is also not your address. State laws require that Drivers Licenses and Vehicles be registered at the address of the owner. If he had no vehicle, no insurance, and/or had a vehicle or drivers license registered at your address then it would likely be impossible to prove that he is only an occasional driver.