The City Council shall have the power to inquire into the official conduct of any department, agency, office, officer or employee of the City, and for that purpose shall have the power to administer oaths, subpoena witnesses, compel the production of books, papers and other evidence material to the inquiry. The City Council may provide by ordinance penalties for contempt in failing or refusing to obey any such subpoena or to produce any such books, papers, or other evidence, and shall have the power to punish such contempt in the manner provided by such ordinance.