What defines direct evidence?

Direct evidence is defined as evidence that directly supports the truth of a proposition without the need for any inference or presumption. For instance, a witness who sees a crime take place can provide direct evidence; their observation is straightforward and does not require interpretation or a leap to conclude what happened. This contrasts with circumstantial evidence, which requires additional reasoning to connect it to a conclusion, as it depends on circumstantial analysis instead of direct observation.

While witness testimony can contribute to a case, it is not inherently classified as direct evidence unless it conveys firsthand knowledge of the facts in question. Moreover, expert opinions may provide interpretations or insights into evidence but do not constitute direct evidence themselves.