In the late 1940s, doctors began prescribing DES (diethylstilbestrol, a synthetic estrogen developed in England in the 1930s) to prevent miscarriages. Years later it was discovered that DES could injure the reproductive system of the daughters of women who had taken it. Penelope Krist claims to be one of those injured daughters. She brought this tort suit in 1987 against Eli Lilly and Company, which along with a number of other drug companies had in 1947, the year before Penelope Krist’s mother became pregnant, begun making and selling DES for the prevention of miscarriages. Under Wisconsin law, which all agree governs the substantive issues in this diversity suit, all that Penelope Krist had to prove in order to recover damages from Lilly was that her mother had taken DES when pregnant with Penelope (which is conceded for purposes of summary judgment); that the DES caused
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the injury for which she sues (also conceded for those purposes); and that Lilly had at the time when Penelope’s mother was pregnant with her “produced or marketed the
type
(e.g., color, shape, markings, size, or other identifiable characteristics) of DES taken by the plaintiffs mother.”
Collins v. Eli Lilly Co.,
The medical records of Penelope Krisf s mother from 1948 do not indicate the brand of DES she took, but the mother (who is 68 years old) testified at her deposition in 1987 about the type of DES she took. She recalled taking, several times a day for at least six straight weeks, small, shiny, smooth, coated, red pills shaped “much like an M & M candy” (that is, convex rather than flat like an aspirin), only smaller — approximately half the size of an aspirin. She testified that in 1952 she had had a total hysterectomy, after which her doctor had prescribed DES to replace the estrogen lost by the removal of her ovaries, and that she had told her husband that the pills she received in 1952 were the same kind that she had taken during her pregnancy in 1948. When this suit was filed she was still taking the pills prescribed back in 1952 — and the pills she was taking were made by Lilly. If they were the same pills she had been taking not only in 1952 but also in 1948, then probably those pills were made by Lilly too; it is on this theory that the plaintiffs counsel named Lilly as the defendant.
After the mother had signed her deposition but before the statute of limitations for suing other manufacturers of DES had expired, Lilly’s counsel informed the plaintiff’s counsel that Lilly had not manufactured
red
DES pills in 1948. Lilly later submitted evidence to that effect (and also to the effect that it had not manufactured coated DES pills in 1948, as she had also testified). The plaintiff does not contest this evidence, yet she failed either to change her theory of the case (as she might have done, we shall see) or to join any additional defendants; her counsel told us that it would have been beyond the plaintiff’s financial means to do so. It is now too late for her to join additional defendants. Although Lilly brought additional drug manufacturers into the case as third-party defendants, to share the burden of liability should the plaintiff win a judgment against it,
Collins v. Eli Lilly Co., supra,
The district court granted Lilly’s renewed motion for summary judgment when, on the morning of trial, the plaintiff’s counsel stated that he intended to call only one witness, the plaintiff’s mother, and added — with admirable candor — that she would testify that the pills she had taken while pregnant with Penelope were small, round, red pills, just as described in her deposition.
The deposition testimony concerning the color and other properties of the pills that Penelope’s mother took during the pregnancy was given without hesitation, qualification, equivocation, uncertainty, misgiving. She expressed no doubt about the accuracy of her recollection; so far as we can glean from the transcript of the deposition, she testified with serene confidence. There are no contradictions, either within the deposition itself or between the deposition and any other evidence in the record, concerning the color of the pills. Lilly had begun manufacturing red DES pills after 1948 but before the prescription issued to the plaintiff’s mother in 1952; and while if no drug company had been manufacturing red DES pills in 1948 it would be plain that the mother’s recollection was faulty, no such evidence was presented. (On the contrary, the record contains a letter from McNeil Laboratories indicating that it manufactured red DES pills in the period when Penelope Krist’s mother was pregnant with her, although it is uncertain whether the McNeil pill was distributed in the area where she lived.) If the mother’s testimony is believed — and the plaintiff’s counsel *296 has suggested no reason not to believe it except that it concerned events almost forty years in the past — then it is plain that Lilly did not cause the injury of which Penelope Krist complains.
In resisting summary judgment, the plaintiff’s counsel argues that he would have asked the jury to disbelieve the mother’s testimony about the color (and coating) of the pills and that the jury might have done so. We are to evaluate the argument by asking whether, if the evidence at trial turned out to be the same as the pretrial evidence — and thus if the mother’s testimony would be the same at trial as the testimony in her deposition — the judge would be required to grant a directed verdict for the defendant. If so, the defendant was entitled to summary judgment.
Anderson v. Liberty Lobby, Inc.,
The jury would be confronted with a case in which a witness friendly to the plaintiff (this is an understatement) testified positively that the pills she took could not have been made by the defendant and in which irrefragable evidence established that those pills could have been made by someone other than the defendant. The only evidence in the record, therefore, would be evidence that Lilly was not the source of the plaintiff’s injury. Lapse of time can distort recollection, but it does not always have that effect and the plaintiff has made no offer to prove that it usually does. The confidence and apparent completeness of the mother’s recollection do not assure its accuracy, but neither do they provide leverage for an argument that it is inaccurate.
A party does not vouch for the truth of every statement of the witnesses he calls, even of the friendly witnesses. Fed.R.Evid. 608 and Note of Advisory Committee on Proposed Rule;
Guenther v. Armstrong Rubber Co.,
There may be answers to these questions, but answers that come out of a scholarly literature of which the plaintiff’s counsel appears to be unaware and which he in any event made no attempt to present through the affidavit of an expert who might later testify at the trial, as in such cases as
United States v. Smith,
The basic problem about testimony from memory is that most of our recollections are not verifiable. The only warrant for them is our certitude, and certitude is not a reliable test of certainty. Many people are certain that God exists. Many are certain that He does not exist. The believer and the nonbeliever are equally certain, but they cannot both be correct. Similarly, the mere fact that we remember something with great confidence is not a powerful warrant for thinking it true. It therefore becomes an empirical question whether and in what circumstances memory is accurate. Cognitive psychologists such as Loftus have tried to answer this question. The answers are controversial. Zaragoza & McCloskey, Misleading Post-event Information and the Memory Impairment Hypothesis: Comment on Belli and Reply to Tversky and Tuchin, 118 J. Experimental Psych. 92 (1989). They are based for the most part on experiments with college students, and as with much experimentation in the social sciences it is uncertain how well the experimental results generalize to “real world” situations. But although the answers certainly are not definitive, they are suggestive. The basic findings are: accuracy of recollection decreases at a geometric rather than arithmetic rate (so passage of time has a highly distorting effect on recollection); accuracy of recollection is not highly correlated with the recollector’s confidence; and memory is highly suggestible — people are easily “reminded” of events that never happened, and having been “reminded” may thereafter hold the false recollection as tenaciously as they would a true one.
All three of these findings could have been used in this case — how effectively we need not decide. The plaintiff’s counsel wanted the jury to pick and choose among the mother’s recollections of the features of the pills — to believe some and disbelieve others. It is difficult to see how the psychological research to which we have referred would have assisted counsel in this delicate operation. But it might have been used in another way: with the aid of an affidavit by an expert witness, the plaintiff’s counsel might have changed the case from one in which the plaintiff can (and is therefore required to) allege and prove what type of DES the mother took to one in which the plaintiff cannot allege or prove this, in which event Wisconsin law allows her to get by with alleging and proving merely that the defendant produced or marketed DES for use in preventing miscarriage during the period in which the plaintiff’s mother was pregnant.
Collins v. Eli Lilly Co., supra,
The plaintiff’s mother was testifying to events that happened forty years ago. Her confidence about those events had less significance than lay intuition would assign to such confidence of recollection. Her recollection that she had taken red pills in 1948 may have been the result of suggestion. She knew that the pills she was taking in 1987 were red DES pills made by Lilly. She knew that she had been taking the identical pills, made by the same company, for at least 25 years. She knew that if she was taking them in 1948 her daughter had a case against Lilly. She did not know (initially) that Lilly had not been making red DES pills in 1948. In these circumstances it was certainly possible for her to “recollect” that the pills she took in 1948 were red even if they actually were a different color. And once her memory was jogged she was likely to persist in her recollection even after she learned that she was not doing her daughter any good by remembering the pills as red. She is an honest person. She refused to change her testimony from what she actually, though quite possibly falsely, believed.
Since as we said a party is not required to vouch for everything his witness says, the plaintiff could have argued that her *298 mother correctly recalled having taken DES but that her recollections concerning the type of DES she took were untrustworthy, thus making this a case where the plaintiff cannot prove what type of DES the mother took. Of course Lilly would be free to call the plaintiff’s mother as its witness and try to prove from her testimony and McNeil’s letter that Lilly did not manufacture the pills she took back in 1948. But the plaintiff could try in turn to counter the damaging parts of the mother’s testimony with testimony by an expert witness about the vagaries of memory. It would be for the jury to decide whether the mother’s recollection about the color of the pills was correct. The case therefore could not be decided on directed verdict, which means that it could not be decided in advance of trial, on summary judgment.
The plaintiff’s counsel did not follow this route. He did not plan to present (presumably through an expert witness) grounds for disbelieving the testimony of the plaintiff’s mother, which exonerated Lilly; he planned to make the mother the plaintiff’s only witness. He intended to present the case not as one in which the plaintiff did not know what type of DES her mother had taken, but as one in which the plaintiff would prove that her mother had taken DES pills made by Lilly — nonred DES pills made by Lilly.
We do not want to be too hard on the plaintiff’s counsel. In forgoing the expert-witness route he may have been concerned with language in opinions of this court that could be thought dismissive of expert testimony in the field of perception and memory. In
United States v. Watson,
Although relevant evidence is presumptively admissible, Fed.R.Evid. 402, and the rule on expert testimony notably liberal, Fed.R.Evid. 702, a district judge has broad discretion to exclude relevant evidence that is confusing or redundant. Fed.R.Evid. 403. Not only is the cost of litigation raised by increasing the amount of evidence at trial, but the accuracy of litigation as a method for finding the truth is impaired when the additional evidence does more to distract or confuse the jury than to enlighten it. Often it does. Information is not effortlessly absorbed, especially information of a technical character. Certainly in routine cases the trial judge is not required to allow wide-ranging inquiry into the mysteries of human perception and recollection. But few cases involve recollections from forty years earlier. Such cases are not routine, and psychological evidence may be helpful to the judges and jurors required to decide them. “Perceptual psychology (a part of experimental psychology) is not ‘junk science.’ ”
Carroll v. Otis Elevator Co.,
There is a tension in our decisions. Hudson and Watson evince a more skeptical view of expert evidence on perception than Carroll does. We need not try to reconcile the tension here. It may have more to do with the particulars of the eases in question than with any deep difference of opinion on the utilization of science in litigation; it may therefore be illusory. An irony of the present case is that the plaintiffs counsel might have been able to turn Hudsonian skepticism to his own advantage. If testimony on the psychology of perception and memory would merely be addressing “an issue of which the jury already generally is aware,” this implies that, even without the aid of an expert witness, the jury in this case (if the case had been allowed to go to a jury) might have tumbled to the unreliability of the mother’s testimony despite the confidence and circumstantial detail with which that testimony was given and the salience of the fact recalled. The jury might, in short, have disbelieved the mother on its own, and if it could have done so rationally, a directed verdict (and therefore summary judgment) would be improper. But remember that the plaintiffs counsel did not want the jury just to disbelieve the mother. If he had wanted that, he would not have called her as a witness. He wanted the jury to believe her description of every feature of the pills except their color and coating. Maybe a psychologist could have guided the jury to such a conclusion (although this seems unlikely), but without such guidance a rational jury could not have reached it. Indeéd, it would have been given no chance to do so. Without an articulated theory of the mother’s partial credibility, there would be no basis for concluding at the close of the plaintiff’s case that the plaintiff had carried its burden of proof on the type of DES that her mother had taken; the judge would grant the defendant’s motion for directed verdict.
There is latent in this discussion a further tension, however: between the orthodox view that treats the issue on summary judgment as whether the moving party would be entitled to directed verdict if the proceeding were a trial rather than a summary judgment proceeding, and the “realist” view that treats the issue on summary judgment as whether the nonmovant has a prayer of winning at trial.
Mason v. Continental Illinois Nat’l Bank,
Rationality is not a synonym for omniscience. If juries could be presumed omniscient, summary judgment could never be granted; the omniscient jury does not need evidence. In deciding what a rational jury could decide, we may not impute to it knowledge that it could have obtained only from expert testimony that no party was prepared to obtain.
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The Wisconsin rule on proof of causation in DES cases (a rule that is not unique to Wisconsin,
Martin v. Abbott Laboratories,
Affirmed.
