4.2: ADMISSIBILITY OF EVIDENCE

Relevant Evidence

Park & McFarland (2020) stated that Federal Evidence Rule 402 declares that irrelevant evidence is inadmissible. Under the Federal Rules, however, evidence is rarely irrelevant, because Fed. R. Evid. 401 deems evidence to be “relevant” if it has “[A]ny tendency to make the existence of any fact that is of consequence to determination of the action more probable or less probable than it would be without the evidence (para. 1).”

This definition of relevance is a broad one. Under it, almost every item of evidence that a rational lawyer might offer would be relevant. For example, evidence that a defendant has been in prior accidents tends slightly to support the inference that the defendant is not a careful driver and then the further inference that the accident at issue was defendant’s fault. The prior accidents would therefore be relevant under the definition of Rule 401.

Such evidence is, however, normally excluded. In a civil case, the evidence would be inadmissible for two reasons. The evidence of other accidents is offered to prove defendant has a character trait of poor driving. Character evidence is not admissible in civil cases (Fed. R. Evid. 404(a)), and in any event character ordinarily may not be proved with evidence of specific acts of conduct (Fed. R. Evid. 405). Even without specific rules about character evidence, however, the evidence may be inadmissible because of Rule 403, discussed below.

Another example is the result of a polygraph test. Probably the result, if obtained by a reliable operator, has enough value to satisfy Rule 401’s definition of relevance. Yet the jury might give the result undue weight or be confused, and the evidence attacking or supporting the validity of the test is likely to be lengthy and tangential. One would expect the result to be excluded under Fed. R. Evid. 403, which provides that although relevant, evidence may be excluded if its probative value is substantially outweighed by the danger of unfair prejudice, confusion of the issues, or misleading the jury, or by considerations of undue delay, waste of time, or needless presentation of cumulative evidence.

Rule 403 is not the only rule designed to prevent the introduction of evidence that is prejudicial or a waste of time; it is merely the most general one. The Fed. R. Evid. also set forth specific rules for certain recurring situations in which the balance of probative value and prejudicial effect tips in favor of exclusion. See, e.g., Fed. R. Evid. 404–405 (character evidence), Fed. R. Evid. 411 (evidence of liability insurance). For purposes of this exercise, you need not become acquainted with any of the relevance rules except Rules 401, 402, and 403. If you think that evidence ought to be excluded under Rule 403 in the computer exercise, say so. If you are right and there is also a more specific rule excluding the evidence, then the computer will tell you (Park & McFarland, 2011).

Maintained in a “Chain of Custody”

Based on Ashcroft, Daniels, & Hart, (2004) in the National Institute of Justice report, the Chain of Custody form document contains a history or chronology of the journey of evidence containing complete information such as subjects / objects involved in collection and analysis activities, date / time and place collection and analysis, full names and nicknames of victims and perpetrators, agency names and full description of evidence. There are 4 things that must be considered in handling Chain of Custody (Widatama, et al., 2018), namely: Flexibility and capability in the chain of custody documentation, Interoperability between evidence obtained with the chain of custody, Security in the chain of custody documentation, Chain making of custody must be understood by everyone, especially when the case is brought to court.