All officers and employees who travel at the expense of the state or any of its departments, agencies, boards, bureaus, or commissions shall file with the Comptroller an itemized statement of all expenses incurred, including those for transportation, in connection with such travel at the expense of the state, agency, institution, board, bureau, or commission before any warrant shall issue for such expenses.
Ala. Code § 41-4-57 (1975)