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Evidence resources for students, bar examinees, and other researchers.

Useful Definitions

Admissibility: The quality or state of being allowed to be entered into evidence in a hearing, trial, or other official proceeding.

Authentication: Broadly, the act of proving that something (as a document) is true or genuine, especially so that it may be admitted as evidence; the condition of being so proved.

Burden of Proof: A party's duty to prove a disputed assertion or charge.

Clear and Convincing Evidence: Evidence indicating that the thing to be proved is highly probable or reasonably certain.

Demonstrative Evidence: Physical evidence that one can see and inspect (i.e. an explanatory aid, such as a chart, map, and some computer simulations) and that, while of probative value and usually offered to clarify testimony, does not play a direct part in the incident in question.

Exhibits: A document, record, or other tangible object formally introduced as evidence in court.

Finder(s) of Fact: One or more persons—such as jurors in a trial or administrative-law judges in a hearing—who hear testimony and review evidence to rule on a factual issue.

Hearsay: Traditionally, testimony that is given by a witness who relates not what he or she knows personally, but what others have said, and that is therefore dependent on the credibility of someone other than the witness. In federal law, a statement (either a verbal assertion or nonverbal assertive conduct), other than one made by the declarant while testifying at the trial or hearing, offered in evidence to prove the truth of the matter asserted.

Preponderance of the Evidence: The greater weight of the evidence, not necessarily established by the greater number of witnesses testifying to a fact but by evidence that has the most convincing force; superior evidentiary weight that, though not sufficient to free the mind wholly from all reasonable doubt, is still sufficient to incline a fair and impartial mind to one side of the issue rather than the other.

Reasonable Doubt: The doubt that prevents one from being firmly convinced of a defendant's guilt, or the belief that there is a real possibility that a defendant is not guilty. “Beyond a reasonable doubt” is the standard used by a jury to determine whether a criminal defendant is guilty.

All definitions come from Black’s Law Dictionary (11th ed. 2019).


Rules of evidence are, as the name indicates, the rules by which a court determines what evidence is admissible at trial. In the U.S., federal courts follow the Federal Rules of Evidence, while state courts generally follow their own rules. See, for example California's evidence rules, Indiana's evidence rules, or Washington's evidence rules. State rules of evidence are generally imposed by the state legislature upon the state courts.

In establishing what evidence is admissible, many rules of evidence concentrate first on the relevancy of the offered evidence. Rules of evidence also allocate among the parties the burden of producing evidence and the burden of persuading the court. The Federal Rules of Evidence also address the admissibility of hearsay and oral testimony.

[Summary from Evidence, Legal Information Institute, (last visited 10/27/2015).]

Subscription Databases

Bloomberg Law: Under the Litigation & Dockets tab, click on Litigation Resource. The Bloomberg BNA Litigation Analysis section provides links to the Digital Discovery & E-Evidence and Expert Evidence Report resources. Also on the page are links to case searches, the Federal Rules of Evidence, and other litigation-related Secondary Sources.

Lexis Advance: Browse Topics—Evidence

Browse Sources—Search “Evidence”—Texas—Texas Courtroom Evidence; Texas Evidentiary Foundations; TX – Texas Local, State & Federal Court Rules

Browse Sources—Search “Evidence”—U.S. Federal—(1) Federal Courtroom Evidence; (2) Federal Evidence Courtroom Manual; (3) Federal Evidence Practice Guide; (4) Federal Rules of Evidence Manual

Westlaw: Under Browse—Secondary Sources—Texts & Treatises—Evidence, various sources are provided, including McCormick on Evidence, Hearsay Handbook, and New Wigmore: A Treatise on Evidence.

Under Tools—West Key Number System, 157: Evidence provides additional topical limits such as Judicial Notice, Hearsay, and Opinion Evidence.

Subject Guide

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