(a) In addition to any other requirements imposed by common law, constitution, statutes, or regulations:

(1) In any contested case, all parties shall be afforded an opportunity for hearing after reasonable notice served personally or by mail;

(2) The notice shall include:

(A) A statement of the time, place, and nature of the hearing;

(B) A statement of the legal authority and jurisdiction under which the hearing is to be held;

(C) A reference to the particular section of the statutes and rules involved;

(D) A short and plain statement of the matters asserted. If the agency or other party is unable to state the matters in detail at the time, the notice may be limited to a statement of the issues involved. Thereafter, upon application, a more definite and detailed statement shall be furnished; and

(E) A statement as to the right of any party to subpoena witnesses and documentary evidence through the agency;

(3) Opportunity shall be afforded all parties to be represented by legal counsel and to respond and present evidence on all issues involved;

(4) Unless precluded by law, informal disposition may be made of any contested case by stipulation, agreed settlement, consent order, or default;

(5) Unless specifically precluded by statute, in addition to the agency, any contested case may be held before any agency representative who has been selected and appointed by the agency for such purpose. Before appointing a hearing representative, the agency shall determine that the person under consideration is qualified by reason of training, experience, and competence;

(6) The agency, the hearing officer, or any representative of the agency authorized to hold a hearing shall have authority to do the following: administer oaths and affirmations; sign and issue subpoenas; rule upon offers of proof; regulate the course of the hearing, set the time and place for continued hearings, and fix the time for filing briefs; dispose of motions to dismiss for lack of agency jurisdiction over the subject matter or parties or for any other ground; dispose of motions to amend or to intervene; provide for the taking of testimony by deposition or interrogatory; and reprimand or exclude from the hearing any person for any indecorous or improper conduct committed in the presence of the agency or the hearing officer;

(7) Subpoenas shall be issued without discrimination between public and private parties. When a subpoena is disobeyed, any party may apply to the superior court of the county where the contested case is being heard for an order requiring obedience. Failure to comply with such order shall be cause for punishment as for contempt of court. The costs of securing the attendance of witnesses, including fees and mileage, shall be computed and assessed in the same manner as prescribed by law in civil cases in the superior court;

(8) A record shall be kept in each contested case and shall include:

(A) All pleadings, motions, and intermediate rulings;

(B) A summary of the oral testimony plus all other evidence received or considered except that oral proceedings or any part thereof shall be transcribed or recorded upon request of any party. Upon written request therefor, a transcript of the oral proceeding or any part thereof shall be furnished to any party of the proceeding. The agency shall set a uniform fee for such service;

(C) A statement of matters officially noticed;

(D) Questions and offers of proof and rulings thereon;

(E) Proposed findings and exceptions;

(F) Any decision (including any initial, recommended, or tentative decision), opinion, or report by the officer presiding at the hearing; and

(G) All staff memoranda or data submitted to the hearing officer or members of the agency in connection with their consideration of the case; and

(9) Findings of fact shall be based exclusively on the evidence and on matters officially noticed.

(b) In proceedings before the agency, the hearing officer, or any representative of the agency authorized to hold a hearing, if any party or an agent or employee of a party disobeys or resists any lawful order of process; or neglects to produce, after having been ordered to do so, any pertinent book, paper, or document; or refuses to appear after having been subpoenaed; or, upon appearing, refuses to take the oath or affirmation as a witness; or after taking the oath or affirmation, refuses to testify, the agency, hearing officer, or other representative shall have the same rights and powers given the court under Chapter 11 of Title 9, the "Georgia Civil Practice Act." If any person or party refuses as specified in this subsection, the agency, hearing officer, or other representative may certify the facts to the superior court of the county where the offense is committed for appropriate action, including a finding of contempt. The agency, hearing officer, or other representative shall have the power to issue writs of fieri facias in order to collect fines imposed for violation of a lawful order of the agency, hearing officer, or other representative.

(c) Subsection (a) of this Code section and the other provisions of this chapter concerning contested cases shall not apply to any case arising in the administration of the revenue laws, which case is subject to a subsequent de novo trial of the law and the facts in the superior court or in the Georgia Tax Tribunal in accordance with Chapter 13A of this title.