What defines relevant evidence according to Rule 401?

Relevant evidence is defined under Rule 401 as evidence that makes a fact more or less probable than it would be without the evidence. Specifically, this means that the information must have a direct connection to the facts at issue in the case, influencing the decision-making process regarding those facts.

For instance, if you are trying to establish that a party was at a particular location during a crucial time, evidence that places that party at that location would be relevant because it directly affects the likelihood that the party was indeed present.

In contrast, evidence that is simply entertaining does not directly impact the determination of the facts relevant to the case and thus fails to satisfy the criteria for relevance. Similarly, evidence that merely supports a side's claims may be persuasive but does not automatically make it relevant unless it meets the threshold of affecting the probability of a fact. Finally, while expert testimony can certainly be relevant, relevance is not restricted to evidence presented by experts alone; many forms of evidence can meet the relevance criterion.