R.I. Gen. Laws § 20-8-8: Powers granted supplemental.

Any powers granted in this chapter to the commission shall be regarded as in aid of, and supplemental to, and in no case a limitation upon, any of the powers vested in the commission by other laws of the state of Rhode Island or by the laws of the states of Maine, New Hampshire, Massachusetts, Connecticut, New York, New Jersey, Delaware, Maryland, Virginia, North Carolina, South Carolina, Georgia, and Florida or by the Congress or the terms of the compact.