(1) Any person aggrieved by a suspected violation of the Age Discrimination in Employment Act shall file with the Equal Opportunity Commission a formal complaint in such manner and form prescribed by the commission. The commission shall make an investigation and may initiate an action to enforce the rights of such employee under the provisions of the act. If the commission does not initiate an action within sixty days after receipt of a complaint, the person aggrieved may bring a civil action in any court of competent jurisdiction for such legal or equitable relief as will effectuate the purposes of the act. Filing of an action by either the commission or the person aggrieved shall be a bar to the filing of the action by the other.
(2) A written charge alleging violation of the Age Discrimination in Employment Act shall be filed within three hundred days after the occurrence of the alleged unlawful employment practice, and notice of the charge, including a statement of the date, place, and circumstances of the alleged unlawful employment practice, shall be served upon the person against whom such charge is made within ten days thereafter.
(3) A respondent shall file with the commission a written response to the written charge of violation within thirty days after service upon the respondent. Failure to file a written response within thirty days, except for good cause shown, shall result in a mandatory reasonable cause finding against the respondent by the commission. Failure by any complainant to cooperate with the commission, its investigators, or its staff, except for good cause shown, shall result in dismissal of the complaint by the commission.
(4) In connection with any investigation of a charge filed under this section, the commission or its authorized agents may, at any time after a charge is filed, issue or cause to be served interrogatories and shall have at all reasonable times access to, for the purposes of examination, and the right to copy any evidence or records of any person being investigated or proceeded against that relate to unlawful employment practices covered by the act and are relevant to the charge under investigation. The commission may seek preparation of and judicial enforcement of any legal process or interrogatories through the office of the Attorney General.