2001 Legal Content Inc. No Claim to Original U.S. Government Works. Notes of Advisory Committee on Rules. The factors to be considered in evaluating the testimony of a witness are perception, memory, and narration. 46 Iowa L.Rev. Sometimes a fourth is added, sincerity, but in fact it seems merely to be an aspect of the three already mentioned.
Standard procedure calls for the swearing of witnesses.
While the practice is perhaps less effective than in an earlier time, no disposition to relax the requirement is apparent, other than to allow affirmation by persons with scruples against taking oaths. The demeanor of the witness traditionally has been believed to furnish trier and opponent with valuable clues. The witness himself will probably be impressed with the solemnity of the occasion and the possibility of public disgrace. Willingness to falsify may reasonably become more difficult in the presence of the person against whom directed. The Sixth Amendment right of confrontation is a manifestation of these beliefs and attitudes.