An expert witness is a person with specialized knowledge, skills, education, or experience in a particular field who is called upon to provide their expertise in legal proceedings to assist the court with understanding complex technical or scientific issues. See Finding and Researching Experts and Their Testimony White Paper.
Parties to a lawsuit have a duty to disclose to opposing counsel the identity of their expert witnesses they intend to call at trial, and to make a fair disclosure of the expert’s views. See Payne v. S.S.
Expert witness reports in civil federal court are governed by Federal Rule of Civil Procedure 26(a)(2)(b). Under this rule, the parties are required to disclose the names of their retained expert witnesses before trial, and to give the opposing party a written report, prepared and signed by the expert witness.
Extortion refers to imposing an action or obtaining something by force or coercion. The crime of extortion does exclude legitimate negotiation methods.
Extradition is the removal of a person (typically referred to as a fugitive) from a requested jurisdiction to another jurisdiction for criminal prosecution or punishment.
Extrinsic fraud is an act of deception or misrepresentation outside the event itself which deprives the victim of material information or participation. Compare to: intrinsic fraud.
An eyewitness is a person who has firsthand knowledge of an event from seeing the event. These people are often called into a court of law to give testimony about what they have seen.
A fact is something that actually occurred or a statement presented as objectively true. Determining facts is a primary role of trial courts.
[Last reviewed in July of 2025 by the Wex Definitions Team]
Failure to state a claim is a defense asserting that even if all the factual allegations in a complaint are true, they are insufficient to establish a cause of action and the case should therefore be dismissed.
