R.I. Gen. Laws § 31-21-10: Restriction of parking on state highways.

The state traffic commission, with respect to highways under its jurisdiction, may place signs prohibiting or restricting the stopping, standing, or parking of vehicles on any highway where in its opinion, as evidenced by resolution or order entered in its minutes, such stopping, standing, or parking is dangerous to those using the highway or where the stopping, standing, or parking of vehicles would unduly interfere with the free movement of traffic on it. The signs shall be official signs and no person shall stop, stand, or park any vehicle in violation of the restrictions stated on the signs.