The process of demonstrating to a judge that the evidence offered is what the proponent claims it is. At trial, all evidence must have a proper foundation before it is presented to the jury. The party offering the evidence bears the burden of laying the foundation and failure to do so will result in the judge excluding the evidence. Often the process of laying a foundation is simple, such as an eyewitness stating that she observed an event and is qualified to testify about what happened. Other examples of laying a foundation include showing an expert witness is knowledgeable in the field she was called to testify about or authenticating physical evidence. Although laying a foundation is a necessary step to admitting evidence, a proper foundation does not guarantee that evidence will ultimately be admitted. The evidence may still be excluded if, for example, it is irrelevant, hearsay, or will unduly prejudice the jury.
[Last updated in June of 2020 by the Wex Definitions Team]