The Secretary of Labor and Employment or his duly authorized representative is hereby empowered to inquire into financial activities of legitimate labor organizations upon the filing of a complaint under oath and duly supported by the written consent of at least twenty percent (20%) of the total membership of the labor organization concerned and to examine their books of accounts and other records to determine compliance or non-compliance with the law and to prosecute any violations of the law and the union constitution and by-laws: Provided, That such inquiry or examination shall not be conducted during the sixty (60) days freedom period nor within the thirty (30) days immediately preceding the date of election of union officials.