D R U G A N D M E D I C A L D E V I C EThis article has two purposes. <strong>The</strong> firstis to examine hindsight bias in pharmaceuticalfailure- to- warn cases and other legalcontexts. <strong>The</strong> second is to offer practicaltips to mitigate the effects of hindsight bias.Hindsight Bias in Failureto-WarnCasesFailure-to-warn cases invite hindsight bias.It is critical at the outsetof a case, or as early aspossible, to develop adefense story that willtake jurors back in time.16 n <strong>For</strong> <strong>The</strong> <strong>Defense</strong> n <strong>October</strong> <strong>2010</strong>To establish a failure- to- warn claim in apharmaceutical product liability case, aplaintiff must prove that the defendant“knew or should have known” that thedrug in question was dangerous but failedto adequately warn either the medical communityor the public. See, e.g., Anderson v.Owens- Corning, 810 P.2d 549 1002–1003(Cal. 1991); Wolfgruber v. Upjohn Co., 423N.Y.S.2d 95, 97 (N.Y. App. Div. 1979). This“knew or should have known” standardopens the door to hindsight bias, bothwhen jurors consider liability and whenplaintiffs bring up after- the- fact- of- injuryremedial measures to establish liability.Of the two aspects of the standard, the“knew” aspect or the “should have known”aspect, it is “should have known” thatmostly leads to hindsight bias. Under the“knew” aspect of the standard, the questionis what the company actually knew atthe time of a plaintiff’s injury. This raisesan objective question. <strong>The</strong> issue turns onactual facts—such as laboratory data orclinical trial results—that show what thecompany’s state of knowledge was duringthe time in question.In contrast, the “should have known”part of the standard is subjective. As a result,there is great opportunity for hindsightbias to creep in and affect the interpretationof the facts. Under the “should have known”standard, the question is not what a companyknew, but what it might have known ifit had simply done more. In some cases, thisprovokes a moral judgment. With the introductionof morality, the question shifts fromwhether a company should have known ofthe risk to whether the company is “good”or “bad.” Jurors perceive that a “good company”would have done more studies beforeputting a drug on the market, and a “badcompany” would not. Because many jurorsalready have a negative view of the pharmaceuticalindustry, they may surrenderto hindsight bias and, on the basis of currentknowledge, find that a defendant is abad company that should have done moreto protect patients.Of course, regardless of the standard,the facts of almost any failure- to- warn casecan invite hindsight bias. Take this classicscenario: (1) a plaintiff is injured while takinga medication; (2) after the injury, dataemerges showing that the medication maycause the injury at issue; and (3) the FDAapproves a revised label—which was not ineffect when the plaintiff took the medication—warningnew patients that the injuryin question is a possible side effect.Under these circumstances, it is not difficultto understand how hindsight biascan play a role in a juror’s decision- makingprocess. Jurors exist in the present in theirown here and now. At the time when theyare asked to apply the “knew or shouldhave known standard,” they are not askedto weigh the issues in the abstract but inthe face of a living, breathing plaintiffwho claims to have been injured by a defendant’sdrug. When confronted with anactual plaintiff and an actual injury, it isdifficult for jurors to put a plaintiff’s storyaside, travel back in time mentally, and explorewhat a manufacturer actually knewor should have known at that time. On topof this, most jurors view their role as unravelingthe mystery of what happened toa plaintiff, why it happened, and decidingwhom to blame. <strong>For</strong> those jurors looking forsomeone to blame, hindsight bias makes iteasier for them to hold a defendant responsibleand to find favorably for the plaintiff.Moreover, and apart from the desire tofind someone or something to attribute aserious injury to, most of us have a difficulttime discarding some of the informationthat we have when we want to make a“correct” judgment. As Fiegenson noted,“jurors are inclined to take into accountwhatever evidence they think will helpthem reach a substantively correct result.”Feigenson, at 105. As a result, jurors tendto resist “debiasing” efforts. Even whenlegal instructions direct jurors to assessthe reasonableness of conduct from thetime before or at the time of harm, jurorsare more likely to take the ex post perspectivebecause this allows them to useall the information that they have at hand.According to Fiegenson, the psychologicalresearch teaches that jurors are morelikely to think, “If I know the outcome ofthe parties’ conduct, why make believe thatI don’t? <strong>The</strong> outcome is what really happened,and taking it into account will helpme to reach a just decision about responsibilityfor what happened.” Id.<strong>The</strong> issue of hindsight bias is furthercomplicated by the doctrine of subsequentremedial measures, which can compoundhindsight bias. A common example of asubsequent remedial measure in failure- towarnpharmaceutical cases is the existenceof a revised label after the fact that warns ofthe very injury alleged by a plaintiff. Whilethe law does not expressly permit a plaintiffto present this evidence during a trial,the plaintiff likely will have many opportunitiesto present evidence of a defendant’schanges that were made to the warningafter a plaintiff suffered an injury.<strong>The</strong> law provides an example of the broadopportunity that plaintiffs can have to presentevidence of subsequent remedial measures.See, e.g., Kimberly Eberwine, Note,Hindsight Bias and the Subsequent RemedialMeasures Rule: Fixing the FeasibilityException, 55 Case W. Res. L. Rev. 633,652–55 (2005). Although prohibited generally,plaintiffs may introduce evidence ofsubsequent remedial measures if the plaintiffseeks to prove the feasibility of a measurethat the defendant could have takenprior to the plaintiff’s injury or when thedefendant claims that “all reasonable carewas being exercised at the time.” Id. at 653(citing Kenny v. Southeastern Penn. Transp.Auth., 581 F. 2d 351, 356 (3d Cir. 1978)).Evidence introduced under this exceptioncan present challenges in a failureto-warn case, as the plaintiff might usethis exception to illustrate the relative easeby which the company could have better,or more adequately, warned the plaintiff
about the potential harm that the plaintiffsuffered. After the fact the addition to thelabel seems so simple to accomplish andis typically reinforced by the prescriberand the patient testifying that the changewould have mattered to them in their riskbenefitanalysis. Even if not taken quite sofar, the plaintiff, at a minimum, readilysuggests that the absence of the remediallanguage led the patient to believe that theprior warning did not apply to him or her.“Why not say more sooner? Why not domore if it might protect even one patientfrom the harm suffered by this plaintiff?That’s what a company that places healthover profits would do, isn’t it? Why nothere?” are often questions posed by a plaintiff’scounsel for jurors hoping to lead jurorsto conclude that it was the absence ofwill and good intentions, not the absenceof knowledge, that motivated the labelingchoices of a company.With evidence of fairly simple remedialsteps, juries may be more inclined to ignoreother evidence on the extensive researchand testing results that led a company toconclude a product exhibited no evidenceof a risk, because they know that the injuryoccurred, and the company later warned ofthe potential for this injury. See, e.g., Eberwine,at 655–58 (discussing the magnifyingeffect of subsequent remedial measuresevidence on hindsight bias in juries). <strong>The</strong>reis often no good reply to the question, whywasn’t more done sooner, why didn’t thecompany discover the risk before it wastoo late for this plaintiff? Thus, evidence ofsubsequent remedial measures directly increasesthe impact of hindsight bias in juriesbecause it supports the assumption thatthe defendant should have known of andwarned about the injury from the outset.Hindsight Bias in Other Areas<strong>The</strong> effects of hindsight bias are not limitedto failure- to- warn cases, and it is worthtaking a moment to discuss some of thoseother areas. See, e.g., Donald S. Davidsonand Marie K.N. DeBonis, Overcoming theEffects of Hindsight Bias, N.Y. L.J. S4, Col.1, Oct. 14, 2003; see Kimberly Eberwine,Note, Hindsight Bias and the SubsequentRemedial Measures Rule: Fixing the FeasibilityException, 55 Case W. Res. L. Rev.633, 636–37 (2005). Two areas that presentvaluable examples of the effects of hindsightbias can be found in patent and negligencelaw.In patent cases, hindsight can affect theissue of obviousness. A lack of obviousnessis one of the key requirements of patentability—thatthe technology in questionwas new and not obvious at the time ofthe invention. It is not difficult to imagine,however, that once a new inventionexists, stepping back in time and assessingwhether it was obvious invites hindsightbias. <strong>For</strong> instance, in KSR Int’l Co. v.Teleflex Inc., 550 U.S. 398, 399 (2007), theU.S. Supreme Court ruled that an inventor’smodification of an existing gas pedaldesign was an obvious change and, therefore,not deserving of patent protection. Itis easy to imagine how, when similar issuescome before a jury, hindsight bias mightaffect the outcome. Once the matter comesbefore a jury, the technology actually doesexist, and the jury is made of aware ofthe process by which the technology wasinvented, thereby potentially leading manyjurors to view the invention as more obviousthan it was at the time of its development.Gregory N. Mandel, Does HindsightBias Affect Obviousness Rulings?, Nat’l L.J.S2, Col. 1, Aug. 18, 2008.Courts and counsel dealing with theseissues in patent cases have suggested waysto mitigate hindsight bias in that context.<strong>For</strong> example, in KSR v. Teleflex, the U.S. SupremeCourt discussed a “teaching, suggestionor motivation” approach in whichthe patent is only proved obvious if priorinformation reveals some motivation orsuggestion that would have generated thetechnology in question. Patent law expertshave also suggested presenting a case thatfocuses on the problem that the inventionsolved. Mandel, Nat’l L.J. S2, Col. 1, Aug.18, 2008.At the core, jurors are often most interestedin the inventor and the inventionstory. While obviousness is the subject ofexpert analysis on the issue of what a personof ordinary skill in the art would have<strong>For</strong> <strong>The</strong> <strong>Defense</strong> n <strong>October</strong> <strong>2010</strong> n 17