(a) Applicability of Federal Rules of Evidence. The Federal Rules of Evidence shall apply to proceedings held under this part only as a general guide. The Presiding Officer may admit any relevent and probative evidence.

(b) Burden of proof. (1) Complaint counsel shall have the burden of sustaining the allegations of any complaint.

(2) Any party who is the proponent of a legal and/or factual proposition shall have the burden of sustaining the proposition.

(c) Presumptions. A presumption imposes on the party against whom it is directed the burden of going forward with evidence to rebut or meet the presumption, but does not shift to such party the burden of proof in the sense of the risk of nonpersuasion, which remains throughout the hearing upon the party on whom it was originally cast.

(d) Admissibility. All relevant and reliable evidence is admissible, but may be excluded if its probative value is substantially outweighed by unfair prejudice or by considerations of undue delay, waste of time, immateriality, or needless presentation of cumulative evidence.

(e) Official notice—(1) Definition. Official notice means use by the Presiding Officer of extra-record facts and legal conclusions drawn from those facts. An officially noticed fact or legal conclusion must be one not subject to reasonable dispute in that it is either (i) generally known within the jurisdiction of the Presiding Officer or (ii) known by the Presiding Officer in areas of his or her expertise; or (iii) capable of accurate and ready determination by resort to sources whose accuracy cannot reasonably be questioned.

(2) Method of taking official notice. The Presiding Officer may at any time take official notice upon motion of any party or upon its own initiative. The record shall reflect the facts and conclusions which have been officially noticed.

(3) Opportunity to challenge. Any party may upon application in writing rebut officially noticed facts and conclusions by supplementing the record. The Presiding Officer shall determine the permissible extent of this challenge; that is, whether to limit the party to presentation of written materials, whether to allow presentation of testimony, whether to allow cross-examination, or whether to allow oral argument. The Presiding Officer shall grant or deny the application on the record.

(f) Objections and exceptions. Objections to evidence shall be timely interposed, shall appear on the record, and shall contain the grounds upon which they are based. Rulings on all objections, and the bases therefore, shall appear on the record. Formal exception to an adverse ruling is not required to preserve the question for appeal.

(g) Offer of proof. When an objection to proffered testimony or documentary evidence is sustained, the sponsoring party may make a specific offer, either in writing or orally, of what the party expects to prove by the testimony or the document. When an offer of proof is made, any other party may make a specific offer, either in writing or orally, of what the party expects to present to rebut or contradict the offer of proof. Written offers of proof or of rebuttal, adequately marked for identification, shall accompany the record and be available for consideration by any reviewing authority.