Whether the car owner's insurance will cover an accident when the vehicle was driven by a person without a valid driver's license will depend upon the terms of the owner's car insurance policy and any exclusions the policy may have written into it.

In general an insurance company will cover those that you allow to use a vehicle. So if a friend borrows your car normally your insurance follows the car and extends to any accident the driver may have while using your vehicle.

Some policies though exclude from accepting claims for drivers that are operating the car without a valid license. Others may allow the claim to go through but this accident claim would likely raise the owner's insurance premiums since it is more of a risk to an insurance company that an insured allows their vehicle(s) to be driven by unlicensed drivers.

It does matter if a person has permission to drive the vehicle or not. Typically one of the prerequisites to an insurance company accepting a claim is that the driver of the vehicle had permission to operate it. If someone unknowingly takes your vehicle without your permission than many times an insurance company will not accept claims.

How permission is given may become a legal issue though depending upon your insurance company's guidelines and state laws. For instance if you have previously allowed the person to drive your car than it could be determined that they had permission to drive your vehicle on this occasion even if they did not specifically ask to use the car.

If someone used your car and was in an accident but found not to have a valid license than you should check with your insurance company to find out if they will accept claims arising from this incident or not.