If the insurer making or issuing a contract or policy at a rate or premium less than that provided by any filing shall, at any hearing held pursuant to §§ 27-9-16 - 27-9-21, or pursuant to § 27-9-15, show to the satisfaction of the commissioner that the rate or premium was used in good faith to meet an equally low or lower net cost to the insured of a competitor, that showing shall be prima facie evidence that the rate or premium used is not unfairly discriminatory, and if the insurer using the rate or premium shall show to the satisfaction of the commissioner that it is writing a kind or class of insurance at a profit, that showing shall be prima facie evidence that the rate or premium used is not inadequate.
R.I. Gen. Laws § 27-9-20