Sec. 12. APPEALS OF BENEFIT DECISIONS. (a) A member who is eligible for retirement for length of service or disability or who has a claim for temporary disability, or any of the member's beneficiaries, who is aggrieved by a decision or order of the board, whether on the basis of rejection of a claim or of the amount allowed, may appeal from the decision or order of the board to a district court in the county in which the board is located by giving written notice of the intention to appeal. The notice must contain a statement of the intention to appeal, together with a brief statement of the grounds and reasons the party feels aggrieved. The notice must be served personally on an officer of the board not later than the 20th day after the date of the order or decision. After service of the notice, the party appealing shall file with the district court a copy of the notice of intention to appeal, together with the affidavit of the party making service showing how, when, and on whom the notice was served.

(b) Not later than the 30th day after the date of service of the notice of intention to appeal on the board, an officer of the board shall file with the district court a transcript of all papers and proceedings in the case before the board. When the copy of the notice of intention to appeal and the transcript have been filed with the court, the appeal is considered perfected, and the court shall docket the appeal, assign the appeal a number, fix a date for hearing the appeal, and notify both the appellant and the board of the date fixed for the hearing.

(c) At any time before issuing a decision on the appeal, the court may require further or additional proof or information, either documentary or under oath. On issuing a decision on the appeal, the court shall give to each party to the appeal a copy of the decision and shall direct the board as to the disposition of the case. The final decision or order of the district court is appealable in the same manner as are civil cases generally.