In case a witness is duly subpoenaed and refuses to attend, or in case a witness appears and refuses to testify or to produce required books or papers, the official body hearing the appeal shall, in writing, report such refusal to the district court of the county, and said court shall proceed with said person or witness as though said refusal had occurred in a proceeding legally pending before said court.
Iowa Code § 400.25
Contempts, chapter 665