Section 22. The journals, files and papers of the senate and of the house of representatives shall be in the custody of their respective clerks during the session to which they relate and after that session they shall be in the custody of the state secretary. The clerk of each branch shall at all times have access to the journals, files and papers. Copies of such journals, files and papers, certified by the clerk of the branch to which they originally appertained or by the state secretary, shall be evidence in like manner as the originals.