R.I. Gen. Laws § 20-13-8
It is unlawful for any person to have in his or her possession a loaded rifle or loaded shotgun or a rifle or shotgun from the magazine of which all shells and cartridges have not been removed, in or on any vehicle or conveyance or its attachments while upon or along any public highway, road, lane, or trail within this state; provided, however, that the provisions of this section shall not apply to deputy sheriffs, the superintendent and members of the state police, prison or jail wardens or their deputies, members of the city or town police force, or other duly appointed law enforcement officers, including conservation officers and park police, nor to members of the army, navy, air force, and marine corps of the United States, the national guard or organized reserves, when on duty, or officers or employees of the United States authorized by law to carry a concealed firearm, nor to any civilian guard or criminal investigator carrying sidearms or a concealed firearm in the performance of his or her official duties under the authority of the commanding officer of the military establishment in the state of Rhode Island where he or she is employed by the United States.
R.I. Gen. Laws § 20-13-8