Conformity to legal rules of evidence shall not be necessary.  All evidence shall be taken in the presence of all of the arbitrators and all of the parties, except where any of the parties is absent, in default or has waived the right to be present.

(b) The arbitrator shall determine the admissibility, relevance, and materiality of the evidence offered and may exclude evidence deemed by the arbitrator to be cumulative or irrelevant.

(c) The arbitrator shall take into account applicable principles of legal privilege, such as those involving the confidentiality of communications between a lawyer and client.

(d) An arbitrator or other person authorized by law to subpoena witnesses or documents may do so upon the request of any party or independently.

R-32. Evidence by Affidavit and Post-hearing Filing of Documents or Other Evidence