(a) Except as provided in subparagraph (b), testimony in the form of an opinion or inference otherwise admissible is not objectionable because it embraces an ultimate issue to be decided by the trier of fact.

(b) No expert witness testifying with respect to the mental state or condition of a defendant in a criminal case may state an opinion or inference as to whether the defendant did or did not have the mental state or condition constituting an element of the crime charged or of a defense thereto. Such ultimate issues are matters for the trier of fact alone.

ADVISORY COMMITTEE NOTE

This rule is the federal rule, verbatim, and comports with Rule 56(4), Utah Rules of Evidence (1971). See Edwards v. Didericksen, 597 P.2d 1328 (Utah 1979).

This rule is identical to Rule 704 of the Federal Rules of Evidence as amended in 1984.