7 Pa. Code § 179.61
(a) Order of hearing. In a proceeding, the party having the burden of proof shall generally go forward, open and close, unless otherwise directed by the presiding officer. The order of testimony may be modified at the discretion of the hearing officer. In determining this order, the presiding officer shall take into consideration the right of the respective party to present the case or defense by oral or documentary evidence, to submit rebuttal evidence and to conduct a cross-examination as may be required for a full and true disclosure of the facts.
(c) Evidence. Neither the Commission, nor the presiding officer will be bound by the technical rules of evidence and all relevant, material and competent evidence may be received in either oral or documentary form, provided, that the Commission or the presiding officer acting hereunder may exclude evidence if:
(2) Its probative value is outweighed by: