The rules in this article are designed to avoid unnecessary restrictions concerning the admissibility of opinion evidence; however, as this note makes clear, an adverse attorney may, by timely objection, invoke the court's power to require that before admission of an opinion there be a showing of the traditional evidentiary prerequisites. Generally, it is not intended that evidence which would have been inadmissible under pre-existing law should now become admissible.

A major objective of these rules is to eliminate or sharply reduce the use of hypothetical questions. With these rules, hypothetical questions should seldom be needed and the court will be expected to exercise its discretion to curtail the use of hypothetical questions as inappropriate and premature jury summations. Ordinarily, a qualified expert witness can be asked whether he has an opinion on a particular subject and then what that opinion is. If an objection is made and the court determines that the witness should disclose the underlying facts or data before giving the opinion, the witness should identify the facts or data necessary to the opinion.

In jury trials, if there is an objection and if facts or data upon which opinions are to be based have not been admitted in evidence at the time the opinion is offered, the court may admit the opinion subject to later admission of the underlying facts or data; however, the court will be expected to exercise its discretion so as to prevent the admission of such opinions if there is any serious question concerning the admissibility, under Rule 703 or otherwise, of the underlying facts or data.