Evidence is information that exists in physical or digital form—such as written agreements and e-mail communications—as well as testimony from witnesses who have personal knowledge of facts relevant to a dispute. Evidence generally must be relevant to be admitted in court and considered by the factfinder (judge or jury) in resolving a lawsuit. And some forms of evidence, such as expert witness testimony, must be shown to be sufficiently reliable (as determined by the judge) to be admitted in evidence.

In Vermont, as in other jurisdictions, evidence must be relevant and reliable to be admissible in court. Relevance means that the evidence must have a direct bearing on the case and be helpful in determining the facts at issue. Reliability pertains to the quality of the evidence, ensuring that it is trustworthy and credible. Physical and digital evidence, such as written agreements and email communications, must be authenticated to be admitted. This involves proving that the evidence is what it purports to be. Testimony from witnesses, including expert witnesses, is subject to the same standards of relevance and reliability. Expert witness testimony, in particular, must be based on sufficient facts or data and be the product of reliable principles and methods that the expert has applied to the facts of the case. The judge acts as the gatekeeper in determining the admissibility of evidence, assessing both its relevance and reliability before it can be considered by the factfinder, whether that be a judge or a jury.