N.D. Cent. Code § 21-02.1-04
Any person interested in the proceedings for issuance or sale of the evidence of indebtedness or proceedings relating to the payment of the evidence of indebtedness may answer the petition. The provisions of title 28 and the North Dakota Rules of Civil Procedure relating to the answer to a complaint are applicable to an answer to a petition. The person answering the petition must be the defendant in the special proceeding and the political subdivision must be the plaintiff. Every material statement of the petition not specifically controverted by the answer, for the purpose of the special proceeding, is to be taken as true. Each person failing to answer the petition is deemed to admit as true all the material statements of the petition. The rules of pleading and practice provided by title 28 and the North Dakota Rules of Civil Procedure which are not inconsistent with the provisions of this chapter are applicable to the special proceeding provided for in this chapter.
N.D.C.C. § 21-02.1-04