The commission shall have power, either as a commission or by any of its members, to subpoena witnesses and take testimony, and administer oaths to any witness in any proceeding or examination instituted before it or conducted by it with reference to any matter within its jurisdiction. In all hearings or proceedings before the commission the evidence of witnesses and the production of documentary evidence may be required at any designated place of hearing; and in case of disobedience to a subpoena or other process the commission or any party to the proceedings before the commission may invoke the aid of any circuit court in requiring the evidence and testimony of witnesses and the production of papers, books and documents. And such court, in case of refusal to obey the subpoena issued to any person or to any public utility subject to the provisions of this chapter, shall issue an order requiring such public utility or any person to appear before such commission and produce all books and papers, if so ordered, and give evidence touching the matter in question. Any failure to obey such order of the court may be punished by such court as contempt thereof. A claim that any such testimony or evidence may tend to criminate the person giving the same shall not excuse such witness from testifying, but such witness shall not be prosecuted for any offense concerning which he is compelled hereunder to testify.