D.C. Mun. Regs. tit. 4, r. 4-422
The hearing examiner may exclude evidence from the record if it is incompetent, irrelevant, immaterial, or unduly repetitious.
Admissions or representations made in connection with prior settlement negotiations shall be excluded from the record.
Hearsay evidence may be admitted into the record at the discretion of the hearing examiner and accorded such weight as the hearing examiner deems warranted by the circumstances.
The parties may stipulate as to any matter of fact. A stipulation shall satisfy a party's burden of proving that fact.
The hearing examiner may, on the motion of a party or sua sponte, take official notice of matters of common knowledge or of any information contained in the records of the Commission, or of other matters that can be verified. Official notice of any fact shall satisfy a party's burden of proving that fact.
Where any decision of the hearing examiner or the Hearing Tribunal rests on official notice of a material fact not appearing in the evidence of the hearing record, any party shall, upon timely request, be given the opportunity to introduce evidence showing to the contrary.
The hearing examiner and the Hearing Tribunal shall not be bound by any other rules of evidence.
D.C. Mun. Regs. tit. 4, r. 4-422