Foundation (evidence)

In common law, a foundation is sufficient preliminary evidence of the authenticity and relevance for the admission of material evidence in the form of exhibits or testimony of witnesses. Although the word "Foundation" does not appear in the Federal Rules of Evidence, scholars have argued that its existence is displayed, albeit implicitly, when viewing all the rules in context. Material evidence is important evidence that may serve to determine the outcome of a case. Exhibits include real evidence, illustrative evidence, demonstrative evidence, and documentary evidence. The type of preliminary evidence necessary to lay the proper foundation depends on the form and type of material evidence offered. Further, a proper foundation must be laid with respect to witness testimony. The type of questioning and evidence necessary to properly lay a witness foundation differs based on what the witness is testifying to, and in what capacity they are testifying. The lack of foundation is a valid objection that an adverse party may raise during trial. The Federal Rules of Evidence states rules regarding a piece of evidence's relevancy and whether or not it is admissible. F.R.E. 402 states relevant evidence is admissible unless otherwise excluded by: "The U.S. Constitution, a federal statute, the Federal Rules of Evidence, or other rules proscribed by the Supreme Court." F.R.E. 402 further provides that irrelevant evidence is inadmissible. F.R.E. 401 outlines the test for whether or not evidence is relevant. The rule states: "Evidence is relevant if: (a) it has any tendency to make a fact more or less probable than it would be without the evidence; and (b) the fact is of consequence in determining the action." In determining these two factors, courts question what issues are consequential in a particular case, and whether the evidence a party seeks to admit has any tendency to prove or disprove a fact at issue. This is called weighing the evidence's probative value, which is a term used to describe the amount which a fact either proves or disproves an issue.