The term “risk” has a fairly precise meaning in scientific parlance. The following is a typical definition:
RISK The probability that an event will occur, e.g., that an individual will become ill or die within a stated period of time or by a certain age. Also, a nontechnical term encompassing a variety of measures of the probability of a (generally) unfavorable outcome. See also probability.
Miquel Porta, ed., A Dictionary of Epidemiology 212-18 (5th ed. 2008)(sponsored by the Internat’l Epidemiological Ass’n).
In other words, a risk is an ex ante cause. The probability is not a qualification about whether there is a causal relationship, but rather whether any person at risk will develop the outcome of interest. Such is the nature of stochastic risks.
Regulatory agencies often use the term “risk” metaphorically, as a fiction to justify precautionary regulations. Although there may be nothing wrong with such precautionary initiatives, regulators often imply a real threat of harm from what can only be a hypothetical harm. Why? If for no other reason, regulators operate with a “wish bias” in favor of the reality of the risk they wish to avert if risk it should be. We can certainly imagine the cognitive slippage that results from the need to motivate the regulated actors to comply with regulations, and at times, to prosecute the noncompliant.
Plaintiffs’ counsel in personal injury and class action litigation have none of the regulators’ socially useful motives for engaging in distortions of the meaning of the word “risk.” In the context of civil litigation, plaintiffs’ counsel use the term “risk,” borrowed from the Humpty-Dumpty playbook:
“When I use a word,” Humpty Dumpty said, in rather a scornful tone, “it means just what I choose it to mean—neither more nor less.”
“The question is,” said Alice, “whether you can make words mean so many different things.”
“The question is,” said Humpty Dumpty, “which is to be master — that’s all.”
Lewis Carroll, Through the Looking-Glass 72 (Raleigh 1872).
Undeniably, the word mangling and distortion have had some success with weak-minded judges, but Humpty-Dumpty linguistics had a fall recently in the Third Circuit. Others have written about it, but I am only just getting around to read the analytically precise and insightful decision in Gates v. Rohm and Haas Co., 655 F.3d 255 (3d Cir. 2011). See Sean Wajert, “Court of Appeals Rejects Medical Monitoring Class Action” (Aug. 31, 2011); Carl A. Solano, “Appellate Court Consensus on Medical Monitoring Class Actions Solidifies” (Sept. 12, 2011).
Gates was an attempted class action, in which the district court denied plaintiffs’ motion for certification of a medical monitoring and property damage class. 265 F.R.D. 208 (E.D.Pa. 2010)(Pratter, J.). Plaintiffs contended that they were exposed to varying amounts of vinyl chloride exposure in air, and perhaps in water at levels too low to detect. Gates, 655 F.3d at 258-59. The class’s request for medical monitoring foundered because plaintiffs were unable to prove that they were all exposed to a level of vinyl chloride that created a significant risk of serious latent disease for all class members. Id. at 267-68.
With no scientific evidence in hand, the plaintiffs tried to maintain that they were “at risk” on the basis of EPA regulations, which set a very low, precautionary threshold, but the district and circuit courts rebuffed this use of regulatory “risk” language:
The court identified two problems with the proposed evidence. First, it rejected the plaintiffs’ proposed threshold—exposure above 0.07µ/m3, developed as a regulatory threshold by the EPA for mixed populations of adults and children—as a proper standard for determining liability under tort law. Second, the court correctly noted, even if the 0.07 µ/m3 standard were a correct measurement of the aggregate threshold, it would not be the threshold for each class member who may be more or less susceptible to diseases from exposure to vinyl chloride.18 Although the positions of regulatory policymakers are relevant, their risk assessments are not necessarily conclusive in determining what risk exposure presents to specified individuals. See Federal Judicial Center, Reference Manual on Scientific Evidence 413 (2d ed.2000) (“While risk assessment information about a chemical can be somewhat useful in a toxic tort case, at least in terms of setting reasonable boundaries as to the likelihood of causation, the impetus for the development of risk assessment has been the regulatory process, which has different goals.”); id. at 423 (“Particularly problematic are generalizations made in personal injury litigation from regulatory positions…. [I]f regulatory standards are discussed in toxic tort cases to provide a reference point for assessing exposure levels, it must be recognized that there is a great deal of variability in the extent of evidence required to support different regulations.”).
Thus, plaintiffs could not carry their burden of proof for a class of specific persons simply by citing regulatory standards for the population as a whole. Cf. Wright v. Willamette Indus., Inc., 91 F.3d 1105, 1107 (8th Cir.1996) (“Whatever may be the considerations that ought to guide a legislature in its determination of what the general good requires, courts and juries, in deciding cases, traditionally make more particularized inquiries into matters of cause and effect.”).
Plaintiffs have failed to propose a method of proving the proper point where exposure to vinyl chloride presents a significant risk of developing a serious latent disease for each class member.
Plaintiffs propose a single concentration without accounting for the age of the class member being exposed, the length of exposure, other individual factors such as medical history, or showing the exposure was so toxic that such individual factors are irrelevant. The court did not abuse its discretion in concluding individual issues on this point make trial as a class unfeasible, defeating cohesion.
Id. at 268. For class actions, the inability to invoke a low threshold of “permissible” exposure may be the death knell of medical monitoring and personal injury class actions. The implications of the Gates court’s treatment of “regulatory risk” is, however, more far reaching. Sometimes risk is not really risk at all. The ambiguity of the risk in risk assessment has confused judges from the lowest magistrate up to Supreme Court justices. It is time to disambiguate. See General Electric v. Joiner, 522 U.S. 136, 153-54 (1997) (Stevens, J., dissenting in part) (erroneously assuming that plaintiffs’ expert witness was justified in relying upon a weight-of-evidence methodology because such methodology is often used in risk assessment).
