R.I. Gen. Laws § 21-16-2
A person, firm, or corporation who shall knowingly sell or expose for sale in any restaurant or other place where food products are sold for consumption on the premises any article of food or food preparation falsely represented as kosher or as having been prepared in accordance with the orthodox or traditional Hebrew religious requirements, either by direct statements, orally or in writing, or by display of the word "kosher" in English or Hebrew letters, or by the display of any sign or mark in simulation of that word, or by the display of any insignia, six-pointed star, or any mark which might reasonably be calculated to deceive or lead a reasonable person to believe that a representation is being made that the food sold is kosher or prepared in accordance with the traditional or orthodox Hebrew religious requirements, or who shall sell or expose for sale in a restaurant or other place both kosher and non-kosher food or food preparation, or who shall prepare, handle, combine, or serve kosher foods in a manner not sanctioned by the traditional or orthodox Hebrew religious requirements, who fails to display on his window signs and all display advertising in block letters at least four inches (4") in height "kosher and non-kosher food served here" shall be guilty of a misdemeanor.
R.I. Gen. Laws § 21-16-2