R.I. Gen. Laws § 46-25-53: Exemption from taxation.

The commission shall not be required to pay state taxes of any kind, and the commission, its projects, property, and moneys and, except for estate, inheritance, and gift taxes, any notes issued under the provisions of this chapter, and the income (including gain from sale or exchange) therefrom, shall at all times be free from taxation of every kind by the state and by the municipalities and all political subdivisions of the state.