DES exposed individuals, send’s post-operative reports also reflected his opinion that plaintiff’s injuries were caused by DES. ” Dr. Town-
The district court held the declarations of Doctors Townsend and Sack were insufficient to defeat summary judgment, stating:
Although expert testimony may defeat summary judgment, the declaration must put forward facts or a reasonable basis for the opinion. A declaration which simply presents an expert opinion without factual support is inadequate to defeat summary judgment.
It is not clear whether the district court ruled that a declaration of expert opinion was not admissible evidence without a recitation of the facts upon which the opinion was based, or that such a declaration in an affidavit, though admissible, was insufficient to create an issue of disputed fact barring summary judgment in the circumstances of this case. We think the ruling was wrong on either ground.
By the express terms of Fed.R.Evid. 705, “[t]he expert may testify in terms of opinion or inference and give his reasons therefore without prior disclosure of the underlying facts or data unless the court requires otherwise.” The court did not “require otherwise” in this case; it simply accorded the declarations of opinion no weight and granted summary judgment against plaintiff.
The court apparently rejected Dr. Sack’s declaration solely on the ground that Dr. Sack’s affidavit did not include the facts on which his opinion was based, remarking “Dr. Sack’s declaration ... does not state facts setting forth the basis for reaching the opinion that plaintiff’s condition was caused by DES.” But Dr. Sack said he based his opinion upon “ ‘changes’ in the tissue of [plaintiff’s] vaginal area.” In view of the presumption established by Rule 705 that supporting facts need not be stated unless requested, it would be unfair to grant summary judgment against plaintiff without affording an opportunity to supply them. If the judge in his discretion decided more detail was desirable, plaintiff should have been permitted to supply it.
The district court discounted Dr. Townsend’s declaration on a different ground, stating, “[Ajlthough he states that plaintiff’s condition is commonly associated with cases involving DES, he offers neither expert testimony that plaintiff was exposed to DES nor facts to support such an opinion.” But Dr. Townsend stated that the changes he observed in plaintiff’s tissue were “commonly seen in DES exposed offspring and rarely seen in non-DES exposed individuals.” This was a statement of fact, and it is a reasonable inference from this fact that plaintiff’s mother had taken DES during her pregnancy with plaintiff. As the party against whom summary judgment was sought, plaintiff was entitled to have such inferences drawn in her favor.
The district court relied on United States v. Various Slot Machines on Guam, 658 F.2d 697, 699-701 (9th Cir.1981), and Thornhill Publishing Co. v. GTE Corp., 594 F.2d 730, 738 (9th Cir.1979). But neither of those cases support the exclusion of the expert opinion evidence in this case.
Thornhill is farthest from the mark. It does not involve expert testimony. The court held inadequate to bar summary judgment the affidavit of a businessman which stated that an alleged violation of the Sherman Act affected interstate commerce, but did not provide specific facts supporting this conclusion. The court held the affidavit failed to meet the requirement of Fed.R.Civ.P. 56(e) that affidavits in opposition to a properly supported motion for summary judgment “must set forth specific facts showing that there is a genuine issue for trial.”
Slot Machines, like this case, does involve affidavits of expert opinion in opposition to summary judgment. The court held that “in the context of a motion for summary judgment, an expert must back up his opinion with specific facts.” 658 F.2d at 700. It thus presents the possible tension between the requirements of Rule 56(e) that such affidavits “must set forth specific facts,” and the provision of Fed.R.Evid.