29 CFR § 2700.63 - Evidence; presentation of case.
(a) Relevant evidence, including hearsay evidence, that is not unduly repetitious or cumulative is admissible.
(b) The proponent of an order has the burden of proof. A party shall have the right to present his case or defense by oral or documentary evidence, to submit rebuttal evidence, and to conduct such cross-examination as may be required for a full and true disclosure of the facts.
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