Okla. Stat. tit. 17, § 122

Upon ascertaining the amount of overcharge due from any public service corporation, person or firm, the Corporation Commission shall have authority to render judgment against such public service corporation, person, or firm, for the amount of such overcharge that may have been collected from the public in violation of any legal rate, or order of the Dommission, if necessary to insure the prompt payment of the same to the Commission. Such judgment shall be a lien upon the property of the public service corporation, person, or firm, and shall be collected in the same manner that fines and penalties imposed by the Corporation Commission are now authorized to be collected by law, and, when collected, shall be paid immediately by the Commission to the parties to whom it is due. Laws 1913, c. 10, p. 10, § 2.