§ 40.150 Rule 401. Definition of “relevant evidence”

Evidence counts as "relevant" if it helps prove or disprove something that actually matters to the case. In other words, if a piece of evidence makes an important fact more likely to be true or less likely to be true, it's relevant.

The bar here is pretty low. Evidence doesn't have to prove something completely on its own. It just needs to nudge the odds one way or the other. For example, a receipt showing someone was in a certain city on a certain day doesn't prove they committed a crime there, but it makes it more likely they were nearby, so it would count as relevant.

This rule is basically the gatekeeper for what evidence gets to be considered at all. If evidence has nothing to do with the facts that matter in the case, it's not relevant, and it usually won't be allowed in. But if it connects in some way to a key question in the case, it clears this first hurdle, even if a judge might still keep it out for other reasons later.