La. Stat. tit. 45 § 1194
Upon the trial of any suit brought to contest any decision, act, rule, rate, charge, classification, or order of the commission, no party shall be allowed to introduce evidence different from that which was offered in the proceeding before the commission, unless the reviewing court determines that the additional evidence is important to the cause and could not have been obtained with due diligence by the party before or during the proceeding before the commission. If the reviewing court determines that a party should be permitted to introduce additional evidence, the court shall remand the proceeding to the commission for the commission to consider the additional evidence. Upon remand, the commission may amend, rescind, or reinstate the action complained of in the suit.
La. R.S. § 45:1194