D.C. Code § 2-1803.03
The reviewing agency shall make a determination of each appeal on the basis of the record established before the administrative law judge or attorney examiner. The reviewing agency shall set aside any administrative law judge or attorney examiner order that is without observance of procedure required by law or regulations, including any applicable procedure required by subchapters I and II of this chapter, or any administrative law judge or attorney examiner order that is unsupported by a preponderance of the evidence on the record. The reviewing agency shall apply the rule of harmless error, and shall have power to affirm, reverse, or modify the order of the administrative law judge or attorney examiner. The reviewing agency may remand a case for further proceedings before the administrative law judge or attorney examiner. A reviewing agency may not modify a monetary sanction imposed by an administrative law judge or attorney examiner if that sanction is within the limits established by law or regulation.
D.C. Code § 2-1803.03