The court may exclude relevant evidence if its probative value is substantially outweighed by a danger of one or more of the following: unfair prejudice, confusing the issues, misleading the jury, undue delay, wasting time, or needlessly presenting cumulative evidence.
Fed. R. Evid. 403
NOTES OF ADVISORY COMMITTEE ON PROPOSED RULES The case law recognizes that certain circumstances call for the exclusion of evidence which is of unquestioned relevance. These circumstances entail risks which range all the way from inducing decision on a purely emotional basis, at one extreme, to nothing more harmful than merely wasting time, at the other extreme. Situations in this area call for balancing the probative value of and need for the evidence against the harm likely to result from its admission. Slough, Relevancy Unraveled, 5 Kan. L. Rev. 1, 12-15 (1956); Trautman, Logical or Legal Relevancy-A Conflict in Theory, 5 Van. L. Rev. 385, 392 (1952); McCormick §152, pp. 319-321. The rules which follow in this Article are concrete applications evolved for particular situations. However, they reflect the policies underlying the present rule, which is designed as a guide for the handling of situations for which no specific rules have been formulated.Exclusion for risk of unfair prejudice, confusion of issues, misleading the jury, or waste of time, all find ample support in the authorities. "Unfair prejudice" within its context means an undue tendency to suggest decision on an improper basis, commonly, though not necessarily, an emotional one. The rule does not enumerate surprise as a ground for exclusion, in this respect following Wigmore's view of the common law. 6 Wigmore §1849. Cf. McCormick §152, p. 320, n. 29, listing unfair surprise as a ground for exclusion but stating that it is usually "coupled with the danger of prejudice and confusion of issues." While Uniform Rule 45 incorporates surprise as a ground and is followed in Kansas Code of Civil Procedure §60-445, surprise is not included in California Evidence Code §352 or New Jersey Rule 4, though both the latter otherwise substantially embody Uniform Rule 45. While it can scarcely be doubted that claims of unfair surprise may still be justified despite procedural requirements of notice and instrumentalities of discovery, the granting of a continuance is a more appropriate remedy than exclusion of the evidence. Tentative Recommendation and a Study Relating to the Uniform Rules of Evidence (Art. VI. Extrinsic Policies Affecting Admissibility), Cal. Law Revision Comm'n, Rep., Rec. & Studies, 612 (1964). Moreover, the impact of a rule excluding evidence on the ground of surprise would be difficult to estimate.In reaching a decision whether to exclude on grounds of unfair prejudice, consideration should be given to the probable effectiveness or lack of effectiveness of a limiting instruction. See Rule 106 [now 105] and Advisory Committee's Note thereunder. The availability of other means of proof may also be an appropriate factor.
COMMITTEE NOTES ON RULES-2011 AMENDMENT The language of Rule 403 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.