Sec. 29. (a) All facts and information in the possession of the commission and all reports, records, files, books, accounts, papers, and memoranda of every nature whatsoever in its possession shall be open to inspection by the public at all reasonable times subject to IC 5-14-3.
(b) Nothing in this section shall be construed to limit the access of parties to rate and finance proceedings before the commission to information in the possession of another party that is relevant to the issues in the proceeding.