The tribunal has proper objection when the trier of fact may be confused or misled by a lawyer serving as both advocate and witness. The opposing party has proper objection where the combination of roles may prejudice that party’s rights in the litigation. A witness is required to testify on the basis of personal knowledge, while an advocate is expected to explain and comment on evidence given by others. It may not be clear whether a statement by an advocate-witness should be taken as proof or as an analysis of the proof.
 To protect the tribunal, paragraph (a) prohibits a lawyer from simultaneously serving as advocate and necessary witness except in those circumstances specified in paragraphs (a)(1) through (a)(3). Paragraph (a)(1) recognizes that if the testimony will be uncontested, the ambiguities in the dual role are purely theoretical. Paragraph (a)(2) recognizes that where the testimony concerns the extent and value of legal services rendered in the action in which the testimony is offered, permitting the lawyers to testify avoids the need for a second trial with new counsel to resolve that issue. Moreover, in such a situation the judge has firsthand knowledge of the matter in issue; hence, there is less dependence on the adversary process to test the credibility of the testimony.
 Apart from these two exceptions, paragraph (a)(3) recognizes that a balancing is required between the interests of the client and those of the tribunal and the opposing party. Whether the tribunal is likely to be misled or the opposing party is likely to suffer prejudice