(1) Unless otherwise required by the court, an expert may testify in terms of opinion or inferences and give reasons without prior disclosure of the underlying facts or data. On cross-examination the expert shall be required to specify the facts or data.
(2) Prior to the witness giving the opinion, a party against whom the opinion or inference is offered may conduct a voir dire examination of the witness directed to the underlying facts or data for the witness’s opinion. If the party establishes prima facie evidence that the expert does not have a sufficient basis for the opinion, the opinions and inferences of the expert are inadmissible unless the party offering the testimony establishes the underlying facts or data.
Presenting an Expert's Opinion: This statute outlines the procedure for how expert testimony is presented and challenged in court.
(1) Opinion First, Details Later:
Generally, an expert can state their opinion first and give their reasons for it without first laying out every single fact or piece of data they relied on. The burden then shifts to the cross-examining attorney to ask about the specific underlying facts and data. This makes the direct examination more efficient and straightforward.
(2) Challenging the Foundation (Voir Dire):
This provides a crucial right to the opposing party. Before an expert states their ultimate opinion to the jury, the opposing lawyer can request to "voir dire" the expert. This is a mini-examination, usually conducted outside the jury's presence, where the lawyer can question the expert about the facts and data they used to form their opinion. If the lawyer can show the judge that the expert lacks a sufficient basis for their opinion, the judge can rule the opinion inadmissible, and the jury will never hear it.
