concurring specially-
[¶ 28] I concur with the majority. I write separately to discuss the role of the district court when the parties fail to offer documentary evidence and fail to make legal arguments.
[¶ 29] Both the majority and the dissent refer to N.D. Admin. Code § 75-02-04.1-02(7) of the child support guidelines, which states: “[i]ncome must be sufficiently documented through the use of tax returns, current wage statements, and other information to fully apprise the court of all gross income.” I understand the frustration of the dissent with the lack of documentation provided by the parties below. However, in this case, I agree with the majority’s conclusion that Hennessee’s sworn affidavit and sworn testimony constituted adequate “other information” to “fully apprise the court of all gross income” under N.D. Admin. Code § 75-02-04.1-02(7).
[¶ 30] Judges are meant to be neutral arbiters that allow the attorneys to advocate on behalf of their clients. See State v. Olson, 244 N.W.2d 718, 723 (N.D.1976) (noting the appearance of justice is diminished when a trial judge “substitutes a three-piece suit of advocacy for his robe of impartiality”). We should not turn the role of trial judges from fair and impartial adjudicators to advocates for obligees. Berg v. Ullman, 1998 ND 74, ¶ 40, 576 N.W.2d 218 (Neumann, J., dissenting). Yet, the dissent concludes that the district court should have required Hennessee to supply documents, in addition to her affidavit and sworn testimony, to determine the amount of her child support obligation. This despite the fact that current tax statements would not have been relevant because the motion to modify the child support was based on a new disability status that would not have been reflected in the tax returns and there would be no current wage statements because she is not employed. In addition, Devine brought neither a motion to compel discovery nor a motion for a continuance of the hearing for Hennessee’s failure to provide discovery.
[¶ 31] We have noted that both parties have an interest in presenting evidence, “because a movant who fails to present evidence runs the risk the motion will not be granted, while an opponent who fails to introduce evidence runs the risk the motion will be granted.” Henry v. Henry, 2000 ND 10, ¶ 7, 604 N.W.2d 234. The parties here requested the hearing and chose to go forward knowing what evidence each had, or, in the ease of Devine, what he did not have. The transcript reflects that Devine wanted to “move forward as fast as possible.” It was a tactical decision by Devine not to bring a motion to compel discovery or request a continuance, perhaps thinking the judge would deny Hennessee’s motion based on a lack of evidence.
[¶ 32] While I agree with the dissent that more documentary evidence may have been helpful to the district court, I disagree that it was mandatory. The district court’s findings of fact are supported by Hennessee’s testimony. The only question here is whether the trial court erred as a matter of law for not requiring the testimony be supported by documentary evidence in addition to her sworn affidavit.
*688[¶ 33] The facts of this case are significantly different than those in Knoll v. Kuleck, 2004 ND 199, 688 N.W.2d 370, on which the dissent relies. In that case, Kuleck, the obligor, quit his job and became self-employed. Tax returns would have been relevant to prove his income, but were not admitted into evidence, even though the obligor brought the records to court. Id. at ¶¶ 2, 15. The district court, in Knoll, admitted its findings were based on an “arbitrary number that doesn’t directly connect to anything.” Id. at ¶ 3. The obligor in this case did not quit her job, rather she became disabled. The district court here did not make an arbitrary finding on income. Rather, it was made based on Hennessee’s affidavit and testimony. This Court has affirmed findings in child support matters based on testimony not supported by documentation of the same. See Schumacher v. Schumacher, 1999 ND 10, ¶ 6, 589 N.W.2d 185 (concluding party was entitled to claim medical deductions to reduce his child support obligations based solely on his testimony, despite no documentation of such expenses). As the majority notes, at ¶ 19, both sworn testimony and affidavits are admissible evidence the district court may consider, and the district court is the ultimate arbiter of credibility. In addition, attached to Hen-nessee’s motion and filed with the court was Exhibit A, a document called “Proposed Ruling Decision” from a Veteran’s Service Center Manager, discussing Hen-nessee’s disability rating, an estimate of her compensation, and other information. Although this exhibit was not offered into evidence, the parties and the court were aware of it, and Hennessee testified about Exhibit A, and the information it reflected, without objection from Devine. As noted in the Knoll case, an obligor’s lawyer may not have the expertise to navigate the increasingly arcane child support rules “that seem destined to eventually riyuval the complexity of the Internal Revenue Code.” Knoll, at ¶ 15 (Sandstrom, J., concurring). As in Knoll, the document in Exhibit A was available, but the obligor’s attorney did not offer it in evidence. Based on these circumstances, the district court did not err in deciding the motion on the evidence before it.
[¶ 34] LISA FAIR McEVERS