327C.10  Investigation and inquiry.
  The department may investigate and inquire into the management of all common carriers subject to its jurisdiction. The department may obtain from the carriers full and complete information necessary to enable the department to perform its duties including the administration of railroad assistance agreements. The department may require the attendance and testimony of witnesses, and the production of all books, papers, tariff schedules, contracts, agreements, and documents, relating to any matter under investigation, and may inspect them; and may examine under oath or otherwise any officer, director, agent, or employee of a common carrier; and may issue subpoenas and enforce obedience to them.
[C97, §2115, 2133; C24, 27, 31, 35, 39, §7878; C46, 50, 54, 58, 62, 66, 71, 73, 75, §474.18; C77, 79, 81, §327C.10; 
81 Acts, ch 22, §22
]
86 Acts, ch 1245, §1959