Cal. Veh. Code § 17200
Where an uninsured owner or operator has obtained a judgment against or agreed to a settlement with the owner or operator of an insured motor vehicle based on the negligence of the insured owner or operator, the amount of the judgment or settlement payable by the insured or his or her insurer shall be reduced by the amount paid or payable to the insured owner or operator or occupants of the insured motor vehicles or their heirs or legal representatives from coverage provided by an uninsured motorist endorsement where the claim of the insured, the owner, or occupants of the insured motor vehicle and the uninsured motorist arise out of the same accident. If the insured or his or her insurer becomes entitled to a reduction, the reduction shall not exceed the amount of the settlement or judgment awarded the uninsured owner or operator.
Ca. Veh. Code § 17200