Conn. Gen. Stat. § 4-178

In contested cases: (1) Any oral or documentary evidence may be received, but the agency shall, as a matter of policy, provide for the exclusion of irrelevant, immaterial or unduly repetitious evidence; (2) agencies shall give effect to the rules of privilege recognized by law; (3) when a hearing will be expedited and the interests of the parties will not be prejudiced substantially, any part of the evidence may be received in written form; (4) documentary evidence may be received in the form of copies or excerpts, if the original is not readily available, and upon request, parties and the agency conducting the proceeding shall be given an opportunity to compare the copy with the original; (5) a party and such agency may conduct cross-examinations required for a full and true disclosure of the facts; (6) notice may be taken of judicially cognizable facts and of generally recognized technical or scientific facts within the agency's specialized knowledge; (7) parties shall be notified in a timely manner of any material noticed, including any agency memoranda or data, and they shall be afforded an opportunity to contest the material so noticed; and (8) the agency's experience, technical competence, and specialized knowledge may be used in the evaluation of the evidence.