R.I. Gen. Laws § 5-8-17: Public works.

This state and its political subdivisions, such as county, city, town, township, borough, or legally constituted boards, districts, commissions, or authorities, shall not engage in the construction of public works involving the practice of engineering unless the engineering drawings and specifications and estimates have been prepared by, and the construction is executed under the direct supervision of, a registered professional engineer or supervision of the Rhode Island department of transportation when applicable to a municipal transportation project. Any contract executed in violation of this section is null and void.