Rule 705. Disclosure of facts or data underlying expert opinion

Disclosure of facts or data underlying expert opinion. The expert may testify in terms of opinion or inference and give reasons therefor without first testifying to the underlying facts or data, unless the court requires otherwise. The expert may in any event be required to disclose the underlying facts or data on cross-examination.

Committee Notes

Advisory Committee’s Notes Under preexisting Alabama law, as well as the common law nationally, an expert could not give an opinion before the jury was made privy to the facts upon which the opinion was based. See Thompson v. Jarrell, 460 So.2d 148 (Ala.1984) (holding that the facts known to the expert or hypothesized must be facts in evidence); Hagler v. Gilliland, 292 Ala. 262, 292 So.2d 647 (1974). Rule 705, like its identical federal counterpart, eliminates the requirement that the underlying facts or data be disclosed as a condition precedent to the expert’s giving an opinion or other testimony. As a practical matter, this abandonment of the historic requirement is aimed primarily at the hypothetical question. See Fed.R.Evid. 705 advisory committee’s note. The hypothetical question has been much criticized for its wordiness and for its allowing counsel to arbitrarily select facts and, thereby, to fashion a hypothesis that is one-sided. See E. Cleary, McCormick on Evidence § 16 (3d ed. 1984); 2 J. Wigmore, Wigmore on Evidence § 686 (Chadbourn Rev. 1979) (observing: “It is a strange irony that the hypothetical question, which is one of the few truly scientific features of the rules of evidence, should have become that feature which does most to disgust men of science with the law of evidence.”); Judge Learned Hand, New York Bar Association Lectures on Legal Topics, 1921-1922 (characterizing the hypothetical question as “the most horrific and grotesque wen on the fair face of justice”); M. Ladd, Expert Testimony, 5 Vand.L.Rev. 414, 426 (1952). It is left to the cross-examiner to elicit the facts or data on which the opinion is based, and the witness must, if asked, disclose such information. See Polk v. Ford Motor Co., 529 F.2d 259, 271 (8th Cir.), cert. denied, 426 U.S. 907 (1976) (holding that “[t]he weakness in the underpinnings of such opinions may be developed upon cross-examination and such weakness goes to the weight and credibility of the testimony”). The