La. Civ. Code art. 3128
Current with operative changes from the 2024 Third Special Legislative Session
The arbitrators may likewise pronounce by their award on the interest and costs; but their silence on that subject is not a cause of nullity. If legal interest would have been payable by law from date of judicial demand, such legal interest awarded by the arbitrators shall attach from the date the matter was submitted to arbitration.
La. C.C. § 3128