28 CFR § 68.37 - Waiver of right to appear and failure to participate or to appear.
(a) Waiver of right to appear. If all parties waive in writing their right to appear before the Administrative Law Judge or to present evidence or argument personally or by representative, it shall not be necessary to give notice of and conduct an oral hearing. A waiver of the right to appear and present evidence and allegations as to facts and law shall be made in writing and filed with the Chief Administrative Hearing Officer or the Administrative Law Judge. Where such a waiver has been filed by all parties and they do not appear before the Administrative Law Judge personally or by representative, the Administrative Law Judge shall make a record of the relevant written evidence submitted by the parties, together with any pleadings they may submit with respect to the issues in the case. Such documents shall be considered as all of the evidence in the case and decision shall be based on them.
(b) Dismissal - Abandonment by party. A complaint or a request for hearing may be dismissed upon its abandonment by the party or parties who filed it. A party shall be deemed to have abandoned a complaint or a request for hearing if: