R.I. Gen. Laws § 31-14-9: Minimum speed.

(a) No person shall drive a motor vehicle at such a slow speed as to impede or block the normal and reasonable movement of traffic except when reduced speed is necessary for safe operation or in compliance with law.

(b) Police officers are authorized to enforce this provision by directions to drivers, and in the event of apparent willful disobedience to this provision and refusal to comply with direction of an officer in accordance with this section, the continued slow operation by a driver shall be a civil violation and is subject to fines enumerated in § 31-41.1-4.