Title 7: Opinions and Expert Testimony
ER 701: OPINION TESTIMONY BY LAY WITNESSES
If the witness is not testifying as an expert, the witness' testimony in the form of opinions or inferences is limited to those opinions or inferences which are
(a) rationally based on the perception of the witness,
(b) helpful to a clear understanding of the witness' testimony or the determination of a fact in issue, and
(c) not based on scientific, technical, or other specialized knowledge within the scope of rule 702.
[Amended effective September 1, 1992; September 1, 2004.] Comment 701 [Deleted effective September 1, 2006.]
ER 702: TESTIMONY BY EXPERTS
If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education, may testify thereto in the form of an opinion or otherwise.
[Adopted effective April 2, 1979.] Comment 702 [Deleted effective September 1, 2006.]
ER 703: BASES OF OPINION TESTIMONY BY EXPERTS
The facts or data in the particular case upon which an expert bases an opinion or inference may be those perceived by or made known to the expert at or before the hearing. If of a type reasonably relied upon by experts in the particular field in forming opinions or inferences upon the subject, the facts or data need not be admissible in evidence.
[Amended effective September 1, 1992.] Comment 703 [Deleted effective September 1, 2006.]
ER704: OPINION ON ULTIMATE ISSUE
Testimony in the form of an opinion or inferences otherwise admissible is not objectionable because it embraces an ultimate issue to be decided by the trier of fact.
[Adopted effective April 2, 1979.] Comment 704 [Deleted effective September 1, 2006.]
ER 705: DISCLOSURE OF FACTS OR DATA UNDERLYING EXPERT OPINION
The expert may testify in terms of opinion or inference and give reasons therefor without prior disclosure of the underlying facts or data, unless the judge requires otherwise. The expert may in any event be required to disclose the underlying facts or data on cross examination.
[Amended effective September 1, 1992.] Comment 705 [Deleted effective September 1, 2006.]
ER 706: COURT APPOINTED EXPERTS
(a) Appointment. The court may on its own motion or on the motion of any party enter an order to show cause why expert witnesses should not be appointed, and may request the parties to submit nominations. The court may appoint any expert witnesses agreed upon by the parties, and may appoint witnesses of its own selection. An expert witness shall not be appointed by the court unless the witness consents to act. A witness so appointed shall be informed of the witness' duties by the court in writing, a copy of which shall be filed with the clerk, or at a conference in which the parties shall have opportunity to participate. A witness so appointed shall advise the parties of the witness' findings, if any; the witness' deposition may be taken by any party; and the witness may be called to testify by the court or any party. The witness shall be subject to cross examination by each party, including a party calling the witness.
(b) Compensation. Expert witnesses so appointed are entitled to reasonable compensation in whatever sum the court may allow. Except as otherwise provided by law, the compensation shall be paid by the parties in such proportion and at such time as the court directs, and thereafter charged in like manner as other costs.
(c) Disclosure of Appointment. In the exercise of its discretion, the court may authorize disclosure to the jury of the fact that the court appointed the expert witness.
(d) Parties' Experts of Own Selection. Nothing in this rule limits the parties in calling expert witnesses of their own selection.
[Amended effective September 1, 1992.] Comment 706 [Deleted effective September 1, 2006.]