R.I. Gen. Laws § 44-20-34: Display of stamps in vending machines.

The tax administrator may, in his or her discretion, prohibit the sale of cigarettes through any vending machine unless that vending machine is so constructed as to permit the tax administrator’s agents to readily determine whether cigarettes being sold through the machine have the necessary tax stamps properly affixed to the packages; any machine used in violation of this prohibition by the tax administrator is presumed to be used for the sale of unstamped cigarettes.