In general, if your son was driving a vehicle that was covered under the same policy that listed him as a driver, he should be covered for the accident up to the limits of applicable coverages. (Unless, he was doing something that went against the policy rules of your husband's car insurance company.) The surcharge for the "at fault" accident will follow your son. In general, your husband's insurance company will raise your husband's car insurance rates if they have to pay for a claim.