2023 Nebraska Revised Statutes › Chapter 27 - Courts; Rules of Evidence › 27-705 - Rule 705. Disclosure of facts or data underlying expert opinion.

27-705.
Rule 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.
Source
Laws 1975, LB 279, § 53;
Laws 1982, LB 716, § 2.
Annotations
1. Testimony admissible
2. Testimony not admissible
3. Miscellaneous
1. Testimony admissible
This section permits admission of an expert opinion without prior disclosure of the underlying facts upon which the expert's opinion is based. An expert's opinion is ordinarily admissible if the witness (1) qualifies as an expert, (2) has an opinion that will assist the trier of fact, (3) states his or her opinion, and (4) is prepared to disclose the basis of that opinion on cross-examination. Gittins v. Scholl, 258 Neb. 18, 601 N.W.2d 765 (1999).
Under this section, an expert can be required to disclose on cross-examination the facts or data underlying his or her opinion; thus, an expert may be cross-examined for the purposes of testing and inquiring into the basis for his or her opinion. State v. Hankins, 232 Neb. 608, 441 N.W.2d 854 (1989).
Statute requires expert to disclose underlying facts and data if required by court but does not require court to allow testimony of all such facts and data. Expert may rely on factors not otherwise admissible, but such reliance will not affect their admissibility. Clearwater Corp. v. City of Lincoln, 207 Neb. 750, 301 N.W.2d 328 (1981).
A witness with experience in testing the type of metal from which a surgical instrument was made but not in testing surgical instruments as such, was qualified to give an opinion as an expert witness about the cause of a break in the surgical instrument. Danielsen v. Richards Mfg. Co., Inc., 206 Neb. 676, 294 N.W.2d 858 (1980).
Under this section, an expert witness may render an opinion without first disclosing the underlying data upon which that opinion is based. Northern Nat. Gas Co. v. Beech Aircraft Corp., 202 Neb. 300, 275 N.W.2d 77 (1979).
Under sections 27-702 and 27-705, an expert witness, qualified to be such, may testify in terms of opinion or inference without prior disclosure of underlying facts or data, the weight of such evidence being for the trier of facts. State v. Journey, 201 Neb. 607, 271 N.W.2d 320 (1978).
2. Testimony not admissible
Where cross-examination of an expert witness discloses there is no adequate factual basis for an expert's opinion, such opinion is irrelevant, is inadmissible, and should be stricken from consideration by a jury on proper motion of the party adversely affected by such irrelevant evidence. Sorensen v. Lower Niobrara Nat. Resources Dist., 221 Neb. 180, 376 N.W.2d 539 (1985).
Expert testimony should not be received, or if received should be stricken, if it appears that the witness is not in possession of such facts as will enable him to express a reasonably accurate conclusion as distinguished from a mere guess or conjecture. Fletcher v. State, 216 Neb. 342, 344 N.W.2d 899 (1984).
Expert testimony should not be received if it appears the witness is not in possession of such facts as will enable him to express a reasonably accurate conclusion as distinguished from a mere guess or conjecture. Clearwater Corp. v. City of Lincoln, 202 Neb. 796, 277 N.W.2d 236 (1979).
The valuation testimony of a landowner's expert witness should have been stricken where his testimony as to the value of the land has no adequate basis. Clearwater Corp. v. City of Lincoln, 202 Neb. 796, 277 N.W.2d 236 (1979).
3. Miscellaneous
An expert is not required to testify to the underlying facts or data before stating his or her opinion. Boyle v. Welsh, 256 Neb. 118, 589 N.W.2d 118 (1999).
A trial court may, either on its own motion or in response to an objection, require an expert to disclose the underlying facts or data upon which the opinion is to be based before permitting the expert to render his opinion. Forehead v. Galvin, 220 Neb. 578, 371 N.W.2d 271 (1985).
Although this rule substantially liberalizes the requirements for an expert witness, it does not mean that such a witness is no longer required to disclose the basis of an opinion if asked to do so by the court or on cross-examination, nor is the jury entitled to consider an opinion with no adequate basis. Dawson v. Papio Nat. N.R.D., 206 Neb. 225, 292 N.W.2d 42 (1980).