Expert Witness Definition and Legal Meaning

On this page, you'll find the legal definition and meaning of Expert Witness, written in plain English, along with examples of how it is used.

What is Expert Witness?

n. Specialist in a subject who may present their expert opinion without being a witness to the occurrence related to the lawsuit or criminal case. If the expert is qualified by evidence of their expertise, training, or special knowledge, they are an exception to the rule against providing an opinion as testimony. The attorney for the party calling the expert must show the expert’s qualifications if they are challenged and the trial judge has the discretion to rule if he/she is qualified as an expert, or is limited on the subjects that they are an expert on. Typically, experts are paid handsomely for their services. In most jurisdictions, both sides exchange the names and addresses of proposed experts during the pre-trial depositions.