(a) Unless specifically stated otherwise, the state officials designated in Code Sections 45-7-4, 45-7-20, and 45-7-21 shall not receive from state funds any compensation, salary, contingent expense allowance, longevity pay, or allowance of any kind other than that specified or provided for in such Code sections. The annual salary for each such official shall be paid in equal monthly or semimonthly installments.

(b) Members of the General Assembly may be reimbursed from funds of the executive and judicial branches of state government for their service upon advisory or investigative boards, committees, commissions, and other similar entities of the executive and judicial branches, subject to the following conditions:

(1) Such reimbursement shall be limited to actual expenses incurred or to actual travel expenses incurred and a per diem allowance not to exceed the per diem allowance paid to members of the General Assembly for service on interim committees of the General Assembly, provided that a mileage allowance for use of a personal motor vehicle may be substituted for actual expenses incurred in the use of the vehicle; and

(2) No such reimbursement shall be paid to any member of the General Assembly for any day upon which the member of the General Assembly receives compensation or reimbursement from the legislative branch of state government.

Members of the General Assembly are expressly authorized to receive reimbursement as provided for in this subsection, and the executive and judicial branches of state government are expressly authorized to pay reimbursement as provided for in this subsection.