La. Stat. tit. 45 § 1176
The commission and any parochial or municipal body having similar powers in the fixing of just and reasonable rates charged or to be charged by public utilities, shall investigate the reasonableness and justness of all contracts, agreements and charges entered into or paid by such public utilities with or to other persons, whether affiliated with such public utilities or not, and shall have the power to disallow as an operating expense of any public utility such part of the amount so paid by it under any such contract or agreement as the commission or parochial or municipal body may find, after hearing, to be unjust or unreasonable and designed for the purpose of concealing, abstracting or dissipating the net earnings of the public utility.
La. R.S. § 45:1176