R.I. Gen. Laws § 15-1-8: Recognition of relationships entered into in another state or jurisdiction.

If two (2) persons are within the jurisdiction of Rhode Island and have a legal union other than a marriage that provides substantially the same rights, benefits and responsibilities as a marriage and the union was validly entered into in another state or jurisdiction and the union is not prohibited by this chapter then they shall be afforded the same rights, benefits and responsibilities as a valid marriage in this state.