(a) A party has the right to conduct discovery, present a direct case, cross-examine witnesses, make oral and written arguments, obtain copies of all pleadings, motions, replies, and other filed documents, receive copies of all notices issued by the commission concerning the proceeding to which the person is a party, and, as directed by the judge, otherwise fully participate as a party in the proceeding. In an enforcement proceeding, no party except the executive director may seek to amend or add to the violations alleged in the petition that initiated the case.(b) Except in enforcement matters, a person may seek leave to withdraw his or her party status at any time upon written request to the judge or by request stated on the record during a hearing. Party status is not withdrawn unless and until the judge grants the request for leave to withdraw.