R.I. Gen. Laws § 42-40-5: Travel expenses of employees of this state.

A sending agency in this state may, in accordance with the travel regulations of that agency, pay the travel expenses of employees assigned to a receiving agency on either a detail or leave basis, but shall not pay the travel expenses of those employees incurred in connection with their work assignments at the receiving agency. If the assignment or detail will be for a period of time exceeding eight (8) months, travel expenses may include expenses of transportation of immediate family, household goods, and personal effects to and from the location of the receiving agency. If the period of assignment is less than eight (8) months, the sending agency may pay a per diem allowance to the employee on assignment or detail.