A witness may testify to a matter only if evidence is introduced sufficient to support a finding that the witness has personal knowledge of the matter. Evidence to prove personal knowledge may consist of the witness's own testimony. This rule does not apply to a witness's expert testimony under Rule 703.
Fed. R. Evid. 602
NOTES OF ADVISORY COMMITTEE ON PROPOSED RULES "* * * [T]he rule requiring that a witness who testifies to a fact which can be perceived by the senses must have had an opportunity to observe, and must have actually observed the fact" is a "most pervasive manifestation" of the common law insistence upon "the most reliable sources of information." McCormick §10, p. 19. These foundation requirements may, of course, be furnished by the testimony of the witness himself; hence personal knowledge is not an absolute but may consist of what the witness thinks he knows from personal perception. 2 Wigmore §650. It will be observed that the rule is in fact a specialized application of the provisions of Rule 104(b) on conditional relevancy. This rule does not govern the situation of a witness who testifies to a hearsay statement as such, if he has personal knowledge of the making of the statement. Rules 801 and 805 would be applicable. This rule would, however, prevent him from testifying to the subject matter of the hearsay statement, as he has no personal knowledge of it. The reference to Rule 703 is designed to avoid any question of conflict between the present rule and the provisions of that rule allowing an expert to express opinions based on facts of which he does not have personal knowledge.
NOTES OF ADVISORY COMMITTEE ON RULES-1987 AMENDMENTThe amendments are technical. No substantive change is intended.
NOTES OF ADVISORY COMMITTEE ON RULES-1988 AMENDMENTThe amendment is technical. No substantive change is intended.
COMMITTEE NOTES ON RULES-2011 AMENDMENT The language of Rule 602 has been amended as part of the restyling of the Evidence Rules to make them more easily understood and to make style and terminology consistent throughout the rules. These changes are intended to be stylistic only. There is no intent to change any result in any ruling on evidence admissibility.