Thank you. If your son is not named on the insurance, then, yes you and your husband can be liable. It is possible that the insurance company would not provide coverage of any accident that he's involved in and then you/your husband would be liable under a theory called "negligent entrustment." This, of course, assumes that your son CAUSED the accident.
If your son did not cause the accident, then you do not have a liability exposure.
You may want to seriously consider signing the car over into your son's name only and having the insurance in his name. That way, you are out of the liability look.
Or, at a minimum, have your son added to the insurance policy
. If he's not on the policy, you are exposed.
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