Keep good science in toxic tort cases; plaintiff lawyers can use a new section of the Restatement (Third) of Torts to help judges widen the gates to causation evidence.

Your auto mechanic does not perform your emergency appendectomy, your family doctor doesn't serve your plumbing needs, and your lawyer does not draw up the blueprints to remodel your home. In an ideal world, judges would not determine the validity of scientists' opinions about science. However, as plaintiffs in civil litigation have noticed, we are not living in an ideal world.

Since the Supreme Court's ruling in Daubert v. Merrell Dow Pharmaceuticals, Inc., (1) plaintiffs injured by toxic exposures have forced the unfortunate reality that judges in many jurisdictions have the power to second-guess the scientific judgment of the plaintiff's expert witnesses. Although Daubert standards do not apply in every jurisdiction, if you practice in toxic torts, you need to know how to meet them. How can plaintiff lawyers best deal with the challenge?

Litigators with substantial experience in the Daubert trenches stress that the first step is preparation. It starts with contemplating Daubert hurdles in determining whether to accept the case, continues with considering Daubert when you choose your experts, and ends only after a final judicial determination that your expert's opinion will be admitted in evidence.

You must learn the science at least as well as the scientists themselves and explain scientific concepts in plain English to the court. And, of course, you must be thoroughly familiar with the legal doctrines and precedents that guide the court's "gatekeeping" function with respect to expert testimony.

If you have managed to do all this--and doing so properly requires outrageous amounts of expertise, time, and money--you have done probably all that you can do to protect your experts from Daubert challenges. The scary truth is that courts have been routinely excluding expert testimony. The Daubert framework--originally intended merely to preclude jurors' consideration of "junk science"--is now often used to exclude well-reasoned scientific opinions by highly regarded scientists with substantial bodies of published data to support their views.

The defense bar has convinced many federal and state court judges that determining causation in a toxic-tort case is a matter of applying objective scientific formulas, which, when properly employed by qualified experts, lead to a single "scientific" outcome. But reasonable, qualified scientists disagree with one another as frequently as reasonable lawyers do--that is, all the time.

Nevertheless, trial lawyers should not be surprised that a misguided perception of science has taken firm root in the judiciary. After all, most judges are no better qualified to address the validity, of an expert's scientific opinions than most auto mechanics are to perform appendectomies. Moreover, as preeminent scholars have observed, the Daubert opinion strongly encourages judges to bias themselves against any scientific opinion that undercuts corporate scientific hegemony:

   The [Daubert] opinion) ... suggests that
   motions for summary judgment or directed
   verdicts may be employed by judges
   who don't trust jurors to treat anticorporate
   science with the appropriate disdain. Since
   those remedies are only effective against
   those who bear the burden of proof, this
   suggests flint the Court supposes that the
   persons most deserving of special protection
   from spurious expertise are corporations
   and other wealthy defendants--the
   very parties most capable of manufacturing
   or purchasing questionable scientific
   opinions. (2)

Recently, the American Law Institute (ALI) joined the effort to counter judicial misunderstanding of scientific evidence. Over the last several years, the ALI, which publishes restatements on many areas of substantive law, has been developing the Restatement (Third) of Torts, and several parts have already been approved.

At the ALI annual meeting in May, the membership tentatively approved the restatement's [section] 28 Comment c, which tackles the problem of scientific proof of causation. (3) The black-letter portion of [section] 28 relates to the burden of proof but does not specifically discuss issues relating to scientific evidence. Nonetheless, Comment c--entitled "Toxic Substances and Disease"--devotes more than 15 pages exclusively to this subject and contains a 36-page Reporters' Note explaining the comment. (4)

Comment c represents more than two years of work by the two Reporters on the torts project, Professor Michael Green of Wake Forest University School of Law and Dean William Powers Jr. of the University of Texas School of Law. A National Academy of Sciences panel made up of epidemiologists, occupational medicine doctors, and toxicologists met with the Reporters and other ALl members to critique an earlier draft of the comment, (5) and the Reporters have acknowledged that Comment c "benefitted significantly" from that discussion. (6)

Plaintiff attorneys will find that Comment c provides a valuable tool to break down judicial misperceptions about scientific evidence. (7) The comment begins by discussing the difference between proof of causation in a typical traumatic-injury case and proof in a case involving toxic-exposure injuries. The introduction describes the special difficulties in the latter type of case:

   When a passenger in all automobile collision
   suffers a broken limb, potential causal
   explanations other than the collision are
   easily ruled out; common experience reveals
   that the forces generated in a serious
   crash can cause a fracture. By contrast, the
   causes of some diseases, especially those
   with significant latency periods, are generally
   much less well understood. Even known
   causes for certain diseases may explain only
   a fraction of the incidence of such diseases,
   with the remainder due to unknown causes.
   ... Science continues to develop a better
   understanding of the biological steps in the
   development of diseases, but current knowledge
   in this respect is considerably more
   modest than for traumatic injury. As a consequence,
   courts in toxic-substances cases
   often must assess various alternative methods
   ... [for determining] factual causation. (8)

After describing the nature of the problem, Comment c points out that many courts have been overzealous in their efforts to shield juries from supposed "junk science":

   Causation is a question of fact normally left
   to the jury, unless reasonable minds cannot
   differ. Appellate or trial court review of jury
   findings affects the allocation of power
   between judges and juries. Until about the
   early 1980s, a qualified expert witness's
   opinion that a toxic agent was a factual
   came of the plaintiff's disease was treated as
   sufficient evidence. A few celebrated cases
   and case congregations, such as the Agent
   Orange and Bendectin litigations, led some
   courts to distrust juries' ability to resolve
   cases based on conflicting general expert-opinion
   evidence. Courts began to scrutinize
   the scientific evidence employed and
   to examine carefully the bases for an expert's
   opinion on factual causation. Some
   courts then tried to develop bright-line
   rules based on science for adequate proof
   of factual causation. The high water mark
   for this overreliance on scientific thresholds
   occurred in the Bendectin litigation when
   one court announced a blanket rule that a
   plaintiff could not make out a sufficient
   case without statistically significant epidemiologic
   evidence. (9)

Here, the comment explicitly refers to the Texas Supreme Court's decision in Merrell Dow Pharmaceuticals, Inc. v. Havner, which held that, to satisfy her burden of proof, the plaintiff, who had taken Bendectin during pregnancy, was required to provide statistically significant epidemiologic evidence that she was more than twice as likely to bear a child with birth defects as were women who had not been exposed. (10)

This "doubling of the risk" requirement has been discussed approvingly by several courts and imposed as a bright-line rule by both the Havner court and the Ninth Circuit on remand from the Supreme Court in Daubert. (11) Comment c debunks the judicial assumptions that underlie these decisions:

   These courts may be relying on a view that
   "science" presents an "objective" method of
   establishing that, in all cases, reasonable
   minds cannot differ on the issue of factual
   causation. Such a view is incorrect. First, scientific
   standards for the sufficiency of evidence
   to establish a proposition may be
   inappropriate for the law, which itself must
   decide the minimum amount of evidence
   permitting a reasonable (and therefore
   permissible) inference as opposed to speculation
   that is not permitted.... Second, scientists
   report that an evaluation of data and
   scientific evidence to determine whether
   an inference of causation is appropriate
   requires judgment and interpretation.
   Scientists are subject to their own value
   judgments and preexisting biases that may
   affect their view of a body of evidence.
   There are instances in which although one
   scientist or group of scientists comes to one
   conclusion about factual causation, they
   recognize that another group that comes to
   a contrary conclusion might still be "reasonable."
   Judgments about causation may
   also be affected by the comparative costs of
   errors, as when caution counsels in favor of
   declaring an uncertain agent toxic because
   the potential harm it may cause if toxic is so
   much greater than the benefit forgone if it
   were pertained to be introduced. Courts,
   thus, should be cautious about adopting
   specific "scientific" principles, taken out of
   context, to formulate bright-line legal rules
   or conclude that reasonable minds cannot
   differ about factual causation. (12)

Explaining methodology

The comment not only takes aim at correcting the general judicial misunderstanding of the nature of scientific reasoning, but also provides guidance in specific areas relating to evidentiary proof of causation.

For example, one of the most frequently cited sources of "methodology" for determining a causal relationship between a particular exposure and a particular disease is a set of guidelines set out by Sir Austin Bradford Hill in the 1960s. This list of considerations, often called the "Hill criteria" or "Hill guidelines," suggests an analytical framework for scientists addressing the question of causation.

But, just as judges generally misperceive science as providing a formulaic, "correct" answer, they also misunderstand the role of the Hill criteria in assessing causation. The framework is necessarily broad, and its use in a particular context is subjective; reasonable scientists may come to different ball equally plausible opinions.

Judging causation

Nonetheless, a search of published federal district court opinions reveals that the Hill guidelines are mentioned by name in 11 cases. In all but one, the court determined that the plaintiff expert's causation testimony should be excluded as unreliable. (13)

This is not because plaintiff experts ignore or misapply the Hill criteria, but because defense lawyers have convinced trial court judges that there is only one way to apply those factors "scientifically." That so called scientific approach nearly always leads to the pro-corporate conclusion that no casual relationship exists.

Comment c explains the Hill guidelines' limitations:

   No algorithm exists for applying the Hill
   guidelines to determine whether an association
   truly reflects a casual relationship is
   spurious. Because the methodology involves
   assessing multiple unranked factors judgment
   is required and in some cases, reasonable
   scientist can come to differing conclusions
   whether a body of epidemiologic
   data justifies an  causation vel
   non. Similarly reasonable scientists may in
   some instances disagree on  whether the
   absence of an association is  is exonerative of
   the agent or is merely inconclusive. (14)

Ultimately the comment should provide helpful guidance to judges who otherwise misunderstand the scientific method, and correcting such judicial misunderstanding should lead to more scientific evidence passing the admissibility threshold.

In the end, juries--not judges--should determine the validity of two competing expert opinions that both typically tally tall within the realm of reasonable science, As Comment c concludes:

   For all of these reasons, reliances on a threshold
   increase in risk or a doubling in incidence
   in a group study to meet the requirement
   of sufficient proof of specific causation
   is usually inappropriate. So long as there is adequate
   evidence of general  causation courts
   should permit the parties to attempt to show based
   on the sorts of evidence described above [such as
   different diagnosis], whether the whether plaintiffs
   disease was more likely than not caused by the
   agent.... [In some cases], an increase of the
   incidence of disease less than a doubling
   may be sufficient to support a finding of
   causation, while in another case, even an
   increased incidence greater than two may
   not be sufficient. (15)

The plaintiff bar should commend the Reporters and other ALI members for important work that has culminated in tentative approval of Comment. In a vacuum, one could reasonably question whether the ALI should be in the business of "restating" science. Nonetheless, the judiciary's need for guidance in this area is clear: The Supreme Court has assigned judges to be "gatekeepers" of scientific proof, and judges around the country have enthusiastically embraced their new role without regard to the limits of their own understanding of scientific principles.

That this guidance comes from the cross-section of the profession represented by the ALI makes it more valuable, less vulnerable to attack on partisan grounds, and more likely to he followed by judges.

Countering misperceptions

The most effective way to praise the ALI's work is to use this tool to change judges' misguided perceptions regarding scientific evidence. Although Comment c has not yet received final approval, the ALI rules encourage citing parts of draft restatements that have received tentative approval, as Comment c has. (16) Besides merely referencing the draft, plaintiff attorneys facing expert admissibility and sufficiency challenges should take the time to explain the scientific process to judges, using the draft as a primary learning aid. Ask your experts to clarify and explain their methodological approach by describing it in terms that Comment c explicitly endorses.

Final approval of the comment by the ALI is expected sometime in 2004 or 2005.

Notes

(1.) 509 U.S. 579 (1993).

(2.) 22 CHARLES ALAN WRIGHT & KEN NETH W. GRAHAM, FEDERAL PRACTICE AND PROCEDURE [section] 5168.1, at 86-87 (Supp. 1998).

(3.) The full text of Tentative Draft No. 3 of Comment c, which was approved in May, is available on the ALI Web site at www.ali.org (click on "ALI Project Online").

(4.) The "black letter" of a section and its comments is formally approved or adopted by the ALI, but the Reporters' Note represents the views of the Reporters alone.

(5.) A transcript of the panel discussion can be found on the Website of the Science, Technology, and Law Program of the National Academies of Sciences at www7.nationalacademies.org/stl/ index.html (last visited Sept. 22, 2003).

(6.) RESTATEMENT (THIRD) OF TORTS [section] 28, cmt. c, Reporters' Note (Tentative Draft No. 3, May 15, 2003) [hereinafter "Comment c"].

(7.) Debates at the 2003 ALI annual convention provide evidence of the value of the comment for plaintiff attorneys. The motion of ALI member and tort "reform" proponent Victor Schwartz that the entire comment be placed in the Reporter's Note--so that none of it would be considered official ALI word--failed by a wide margin.

(8.) Comment c, supra note 6, at 144.

(9.) Id. at 145.

(10.) 953 S.W.2d 706 (Tex. 1997).

(11.) See Daubert v. Merrell Dow Pharms., Inc., 43 F.3d 1311, 1320-21 (9th Cir. 1995).

(12.) Comment c, supra note 6, at 145-46.

(13.) See, e.g., Soldo v. Sandoz Pharms. Corp., 244 F. Supp. 2d 434 (W.D. Pa. 2003); Magistrini v. One Hour Martinizing Dry Cleaning, 180 K Supp. 2d 584 (D.N.J. 2002), aff'd, 2003 WL 21467223 (3d Cir. June 25, 2003); Castellow v. Chevron U.S.A., 97 F. Supp. 2d 780 (S.D. Tex. 2000). The decision that admitted the plaintiff experts' causation opinion is Louderback v. Orkin Exterminating Co., 26 F. Supp. 2d 1298 (D. Kan. 1998).

(14.) Comment c. supra note 6, at 150-51.

(15.) Comment c, supra note 6, at 154 (emphasis added).

(16.) See Zenith Radio Corp. v. Hazeltine Research. Inc., 401 U.S. 321, 345 (1971) (citing adopted tentative draft of the Restatement (Second) of Torts).

STEVE BAUGHMAN JENSEN is a shareholder at Baron & Budd in Dallas.