A. At any time after the assessment of any tax or the denial of a refund or credit, if the secretary in good faith is in doubt of the correctness of the denial or liability for the payment of an assessment, the secretary may compromise the asserted liability for taxes or the denial by entering with the taxpayer into a written agreement that adequately protects the interests of the state.
B. The agreement provided for in this section is to be known as a "closing agreement". If entered into after any court acquires jurisdiction of the matter, the agreement shall be part of a stipulated order or judgment disposing of the case.
C. As a condition for entering into a closing agreement, the secretary may require the taxpayer to furnish security for payment of any taxes due according to the terms of the agreement.
D. A closing agreement is conclusive as to liability or nonliability for payment of assessed taxes or the denial of a refund or credit relating to the periods referred to in the agreement, and except upon a showing of fraud or malfeasance, or misrepresentation or concealment of a material fact:
(1) the agreement shall not be modified by any officer, employee or agent of the state; and
(2) in any suit, action or proceeding, the agreement or any determination, assessment, collection, payment, abatement, refund or credit made in accordance therewith shall not be annulled, modified, set aside or disregarded.