Opinions and Expert Testimony
Explore the rules regarding admissibility of both lay and expert opinion testimony, as well as the Daubert standard for reliability as it relates to expert opinion.
Witnesses who testify in court are usually limited to statements of fact. If you recall, one of the requirements for witness competency is personal knowledge of the matter, defined as an observation of a perceived fact. However, there are two exceptions that allow witnesses to testify to opinions or unobserved facts in order to explain confusing or complicated matters to the court: A witness may provide lay opinions or expert testimony to help explain what certain facts mean or imply in a...