N.D. Cent. Code § 28-31-09
In an original cause in the supreme court, whether in response to an order to show cause or an alternative writ of any kind, the respondent shall appear by written motion, answer, or return. This may be submitted to the supreme court without waiver at one or different times, as may best suit the convenience of the court and the parties, for purposes of expedition. Upon a hearing, the parties may present, in support of the issues, affidavits and counter affidavits. If, for the determination of controverted facts, a further hearing and additional evidence become necessary, the court, upon application made therefor, shall determine the method of taking, and the time for the return of, additional testimony, whether the same be by additional evidence, by deposition, or by oral testimony taken before the court, or by reference either to a trial court or some designated commissioner or referee.
N.D.C.C. § 28-31-09