R.I. Gen. Laws § 24-10.1-9: Interpretation.

(a) Nothing in this chapter shall be construed to abrogate or affect the provisions of any lawful ordinance, regulation or resolution, which are more restrictive than the provisions of this chapter.

(b) Notwithstanding any other provisions of this chapter or the general or public laws to the contrary, the director of the department of transportation shall not regulate any on-premise or off-premise non-commercial protected speech contained within any advertising display authorized by this chapter.