Iowa Code Title VIII. Transportation [Chs. 306-330B] § 321.174. Operators licensed--operation of commercial motor vehicles

1. A person, except those expressly exempted, shall not operate any motor vehicle upon a highway in this state unless the person has a driver's license issued by the department valid for the vehicle's operation.

3. A licensee shall have the licensee's driver's license in immediate possession at all times when operating a motor vehicle and shall display the same upon demand of a judicial magistrate, district associate judge, district judge, peace officer, or examiner of the department. If the licensee has been issued a commercial learner's permit, the licensee's driver's license includes both the licensee's commercial learner's permit and the licensee's underlying commercial or noncommercial driver's license. However, a person charged with violating this subsection shall not be convicted and the citation shall be dismissed by the court if the person produces to the clerk of the district court, prior to the licensee's court date indicated on the citation, a driver's license issued to that person and valid for the vehicle operated at the time of the person's arrest or at the time the person was charged with a violation of this section. Upon dismissal, the court or clerk of court shall assess the costs of the action against the defendant named on the citation.