Iowa Admin. Code r. 129-6.10
The presiding officer may, on the presiding officer's own motion or as requested by a party, order hearings or argument to be held by telephone conference or other electronic means in which all parties have an opportunity to participate. The presiding officer will determine the location of the parties and witnesses for telephone or other electronic hearings. The convenience of the parties or witnesses, as well as the nature of the case, shall be considered when the location is chosen. The presiding officer may permit any witness to testify by telephone or other electronic means. If there is a prehearing conference, the parties shall disclose at or before the prehearing conference whether any witness will be testifying by telephone or other electronic means. If there is not a prehearing conference, the parties shall disclose not less than three business days prior to the hearing date whether any witness will be testifying by telephone or other electronic means unless any law, rule, or order of the presiding officer requires disclosure sooner. Objections, if any, shall be filed and served on all parties at least three business days in advance of hearing.
Iowa Admin. Code r. 129-6.10