(a)

(1) The state board of equalization shall proceed to examine such assessments as made by the comptroller of the treasury, and is authorized to increase or diminish the valuation placed upon any property valued by the comptroller of the treasury, and is further authorized to require of the comptroller of the treasury any additional evidence touching one (1) or more of the properties assessed, and shall consider such additional evidence so furnished in fixing the correct value of any property so assessed, and the assessments shall not be deemed complete until corrected and approved by the board; the board is authorized to call the comptroller of the treasury at any time to perform the duties imposed upon it; provided, that if the board so desires, it shall have the power, without referring any assessment to the comptroller of the treasury, to employ experts, accountants, and to call witnesses to testify upon any assessment certified to it by the comptroller of the treasury. The board shall have the same powers to compel attendance of witnesses, production of books, papers, and documentary evidence as is by this chapter given to the comptroller of the treasury.

(2) The board has the right to call upon the federal highway administration for any valuations of property in the office of the administration and evidence in possession of such administration in support of such valuations.

(b) All of the evidence thus acquired by the board shall be considered by it in addition to the evidence transmitted to it by the comptroller of the treasury in support of the assessment so fixed by the comptroller of the treasury.

(c) Any expense incurred by the board in calling for the additional proof as to the value of any property certified to it by the comptroller of the treasury shall be by the board certified to the commissioner of finance and administration and paid by the commissioner out of any moneys in the state treasury not otherwise appropriated.