La. Stat. tit. 45 § 1196
Any person or body, politic or municipal, complaining of anything done or omitted to be done by any railroad, steamboat or other watercraft, sleeping car, express, telephone or telegraph company, or other person subject to regulation and control by the commission, in contravention of any order, rule, regulation, rate, or classification adopted or approved by the commission may apply to the commission by petition, briefly stating the facts. A statement of the complaint shall be forwarded by the commission to the common carrier, who shall be called upon to satisfy the complaint, or to answer the same in writing within a reasonable time, to be specified by the commission. If such persons subject to the control of the commission shall make reparation for the injury alleged to have been done, the common carrier shall be relieved of liability to the complainant only for the particular violation complained of. If the complaint is not satisfied within the time specified, or there shall appear to be any reasonable ground for investigation of complaint, it shall be the duty of the commission to investigate the matters complained of as it deems proper.
La. R.S. § 45:1196