Treatment of witnesses, litigants and other counsel.

(a) A practitioner shall always treat adverse witnesses and other litigants with fairness and due consideration. He should never minister to the prejudice of a client in a trial or conduct in a cause. The client has no right to demand that the practitioner representing him abuse the opposing party or indulge in offensive personal attacks. (b) A practitioner shall not attempt to obstruct Board investigations or corruptly to influence witnesses and potential witnesses during an investigation. (c) In conducting a case it is improper for a practitioner to allude to the personal history or the personal peculiarities or idiosyncracies of practitioners on the other side, or otherwise engage in personal abuse of other practitioners.