9 CFR § 202.104 - Rule 4: Agency action.
(a) Informal disposition. If there appears to be any reasonable ground for doing so, the Agency Head shall investigate the matter complained of. If the Agency Head reasonably believes that there are not sufficient facts to form the basis for further proceeding, the matter may be dropped, without prejudice to subsequent court action on the same cause of action; if it is dropped, the person filing the complaint shall be informed. If the statements in the complaint, and information obtained in the investigation, seem to warrant such action, the Agency Head may make an effort to obtain the consent of the parties to an amicable or informal adjustment of the matter by communication with the parties or their attorneys or representatives. Such communication may be written or oral or both.
(b) Service of complaint. If the matter is not disposed of as provided in paragraph (a), the complaint, together with any amendment which has been filed, shall be served on the respondent with a notice that an answer is required.
(c) Service of report of investigation. A report prepared by the Agency, of its investigation of the matter complained of, and supplements to such a report, may be served on the parties and made a part of the record of the proceeding. Whether such a report or supplement shall be prepared, and whether it shall be served on the parties and made a part of the record, and its contents, shall be in the discretion of the Agency Head. The Judicial Officer shall consider information in such a report or supplement as part of the evidence in the proceeding, to the extent that such information is relevant and material to the proceeding. Any party may submit evidence in rebuttal of such information as is provided generally in these rules for the submission of evidence. Oral testimony, to the extent credible, shall be given greater weight as evidence than such information.