R.I. Gen. Laws § 35-10-5: Investment of sinking fund moneys.

Notwithstanding the provisions of this chapter, any sinking fund money shall be invested in bonds or certificates of indebtedness of the state, or in bonds of the United States or of any state of the United States, or, in the commission’s discretion, in the interest bearing notes or bonds of any city, town, or fire district in the state, or of any county, city, or town in any state of the United States.