Ala. Code § 40-21-18
The Department of Revenue shall carefully examine and consider said statements and information and shall hear evidence and secure further and additional information as far as may be in its power, whenever it may deem it necessary to do so, to show the true value of properties of such corporations, associations, companies, and individuals and the true value of that portion thereof which is situated within this state and within the respective counties, cities, towns, or other tax districts in this state; and each interested company, corporation, association, or individual may appear before said department and introduce material and relevant testimony before the same touching the true value of said property within this state and the apportionment thereof. From these statements, evidence and information adduced before it, the Department of Revenue shall ascertain, fix, and determine the true value of such property and of the portion thereof which is situated within this state and the respective value of the several portions within the different counties and cities, towns and school districts, or other tax districts having a special assessment in this state, in which such portions are taxable; and for that purpose said department may require and compel by subpoenas to be issued by it any person or persons, or the officers and agents, or any of them, of any company, corporation, or association embraced by the provisions of this title to appear before it with such books, papers, documents, and information as the department may require and to submit themselves to examination by said department, and it shall have all the powers with respect thereto conferred upon it by this title.
Ala. Code § 40-21-18 (1975)