By ignoring Milward’s expert witnesses’ omissions from, and abridgements of, WOE and IBE, the appellate court blinded itself to these witnesses’ distortions of scientific method. The need for judgment, which the Milward court was keen to honor, does not mean that there are not aberrant or deviant judgments, or deviations from the standard of scientific care that are disqualifying. The need for judgment must also allow for equipoise and uncertainty that stands in the way of an inculpatory or exonerative verdict. And then there is the business of questionable research practices that subvert causal judgment. The district court had followed and acknowledged the showing of questionable research practices that pervaded Martyn Smith’s for-litigation opinions. The cheerleaders for Milward seem eager to obscure these practices by their insistence that causation is, after all, only a judgment.
The Milward decision, in its embrace of some truly aberrant methodology and judgment, and some absence of methodology, made some of its own whoopers. Martyn Smith’s incompetent analyses of the epidemiologic evidence had been thoroughly debunked in the district court, but the circuit court glibly adopted Smith’s characterizations. The appellate court failed to understand and come to grips with Smith’s rejiggering of data, and his inconsistently redefining exposures and outcomes in epidemiologic studies to make up new, fanciful results that favored his WOE-ful opinion. The appellate court also failed to understand that scientific judgment is not some vague, amorphous, unstructured decision that turns on whatever looks to be “explanatory.” Even the International Agency for Research on Cancer, which issues hazard classifications that are distorted by non-scientific precautionary principle reasoning, insists that three streams of evidence (epidemiologic, toxicologic, mechanistic) be considered separately, in accordance with criteria, with attention to the validity of each study, and synthesized into a judgment of causality following a carefully structured analysis.[1]
The appellate court in Milward took the demonstration of Smith’s failure to calculate odds ratios correctly to be something that merely went to the weight, not the admissibility, on the theory that a jury, which does not have access to the Reference Manual or to the actual studies as published, could sort it all out. And yet, when the court improvidently set out a definition of what an odds ratio is, it bungled the definition beyond understanding:
“An odds ratio represents the difference in the incidence of a disease between a population that has been exposed to benzene and one that has not.”[2]
The court’s definition is not even wrong. The difference between incidence of a disease in an exposed group and a non-exposed group is the risk difference. It is not an odds ratio. Perhaps the court might have realized what most third graders know, that there is a difference between a ratio (division) and a difference (subtraction). And of course, the odds of exposure is not the same as the incidence of a disease. The relevant odds ratio represents the odds of exposure in cases with APML diagnoses divided by the odds of exposure in study subjects without APML. The odds ratio does involve measurements of incidence although in some cases the odds ratio will approximate a risk ratio, which does involve a ratio of incidences. This is not some hyper-technicality; it is a vivid display that Chief Judge Lynch, writing for a panel of three judges of the First Circuit, had no idea of what she was reviewing or writing.
Richter and Capra devote two pages to a discussion of the Milward case and its embrace of WOE and IBE. There is not, in this discussion, a single adjective of approval or of disapproval. The attention to this one intermediate appellate court opinion far exceeds any other case decided at a level below the Supreme Court, and an engaged reader must ask why the authors of the first chapter of the new Reference Manual wrote about this case at all, especially given the 2023 amendments to Rule 702, which would suggest that Milward was bad law when decided in 2011, and clearly and emphatically bad law in December 2025, when the new Manual was published.
The chapter provides one not-so-subtle clue of the authors’ intent. At the conclusion of their extended, uncritical, and incomplete exposition of Milward,[3] Richter and Capra refer the reader to a law review symposium,[4] “[f]or a detailed analysis of the Milward decision and the weight of the evidence approach to scientific reasoning.” Like Richter and Capra’s coverage of Milward, the cited symposium was hardly an objective analysis; rather, it was more like a drunken celebration at a family reunion.
There have been many law review articles that have discussed the Milward case, but Richter and Capra chose to cite to one particular symposium, which was sponsored by two corporations, the Center for Progressive Reform (CPR) and the Robert A. Habush Foundation. The Center for Progressive Reform (CPR) is a not-for-profit corporation. Its website describes the CPR as a “research and advocacy organization that works in the service of responsive government; climate justice, mitigation, and adaptation; and protecting against environmental harm.”[5] CPR describes one of its key activities as defending science from corporate interference. Presumably its own corporate activities and those of the lawsuit industry are acceptable, but those of corporate manufacturing industry are not. From reviewing CPR’s website, it is not clear that the CPR believes manufacturing corporations should even be allowed to defend against lawsuits. Milward’s retained expert witness Carl Cranor is a “member scholar” at CPR, which makes CPR’s sponsorship of the symposium rather incestuous.[6]
CPR is also apparently comfortable with one highly politicized “corporation,” namely the American Association for Justice (AAJ), which is the trade group for the American lawsuit industry.[7] The AAJ describes itself as a corporation, or a “collective,” that supports plaintiff trial lawyers as their “collective voice … on Capitol Hill and in courthouses across the nation … .” The Robert A. Habush Foundation is endowed by the AAJ, and serves its “educational” mission. Through the Habush Foundation, the AAJ funds educational programs, “think tanks,” and writing projects designed to influence judges, law professors, lawyers, and the public, on issues of importance to the AAJ: “the civil justice system and individual rights” for bigger, better, and more profitable litigation outcomes. The AAJ may be a “not-for-profit” corporation, but it represents the interests of one of the most powerful, wealthiest, interest groups in American society — the plaintiffs’ bar.
The Milward symposium agenda and papers from its participants were published at the website for the Wake Forest Journal of Law and Public Policy, but now are marked as “currently private. If you would like to request access, we’ll send your username to the site owner for approval.”
The symposium cited by Richter and Capra for “analysis,” was very much a family affair. The choice of venue, at the Wake Forest Law School, was connected to the web of interests involved. CPR board member, Sid Shapiro, is a law professor at Wake Forest. Shapiro presented at the symposium, along with the Wake Forest professor Michael Green. Cranor, Shapiro’s CPR colleague, and party expert witness for plaintiff, presented.[8] There was only one practicing lawyer who presented at the symposium, Steven Baughman Jensen, who was a past chair of the AAJ’s Section on Toxic, Environmental, and Pharmaceutical Torts. Jensen represented Milward, and hired Cranor as one of the plaintiff’s expert witnesses. Attorney Jensen’s contribution to the symposium has been published along with Cranor’s as well, in the proceedings of the Milward symposium were published volume 3, no. 1 of the Wake Forest Journal of Law and Public Policy,[9] which is now also marked private. Jensen also published an abbreviated paean to Milward in in the AAJ’s trade journal.[10] No defense counsel or defense expert witness participated at the symposium, referenced by Richter and Capra.
Consistent with the financial, advocacy, and political interests of the symposium sponsors, the articles are almost all partisan high-fives for the Milward decision. Writing for the Federal Judicial Center and the National Academies, the authors of a chapter on the law of expert witnesses, a legal issue, for the Reference Manual, should have been aware of the partisan nature of the CPR-AAJ sponsored symposium. They should have flagged the advocacy nature of the symposium, and identified the funding sources and the conflicts created. Furthermore, Richter and Capra should have cited papers that criticized the Milward case, from various perspectives, including its failure to adhere to the law of Rule 702.[11] Their failure to do so is a significant failure of this chapter.
[1] IARC MONOGRAPHS ON THE IDENTIFICATION OF CARCINOGENIC HAZARDS TO HUMANS – PREAMBLE (2019).
[2] Milward, 639 F.3d at 23.
[3] Richter & Capra at 33n.96 (“For a detailed analysis of the Milward decision and the weight of the evidence approach to scientific reasoning…”).
[4] Symposium: Toxic Tort Litigation: After Milward v. Acuity Products, 3 WAKE FOREST JOURNAL OF LAW & POLICY 1 (2013).
[5] The Center for Progressive Reform, at https://progressivereform.org/, last visited on Feb. 24, 2026
[6] Carl Cranor Biography, Center for Progressive Reform, Member Scholars, at https://progressivereform.org/member-scholars/
[7] The AAJ was previously known by the more revealing name, Association of Trial Lawyers of America (ATLA®).
[8] Carl F. Cranor, Milward v. Acuity Specialty Products: Advances in General Causation Testimony in Toxic Tort Litigation, 3 WAKE FOREST JOURNAL OF LAW & POLICY 105 (2013).
[9] Steve Baughman Jensen, Sometimes Doubt Doesn’t Sell: A Plaintiffs’ Lawyer’s Perspective on Milward v. Acuity Products, 3 WAKE FOREST JOURNAL OF LAW & POLICY 177 (2013).
[10] Steve Baughman Jensen, Reframing the Daubert Issue in Toxic Tort Cases, 49 TRIAL 46 (Feb. 2013).
[11] See Eric Lasker, Manning the Daubert Gate: A Defense Primer in Response to Milward v. Acuity Specialty Products, 79 DEF. COUNS. J. 128, 128 (2012);
David E. Bernstein, The Misbegotten Judicial Resistance to the Daubert Revolution, 89 NOTRE DAME L. REV. 27, 29, 53-58 (2013); David E. Bernstein & Eric G. Lasker, Defending Daubert: It’s Time to Amend Federal Rule of Evidence 702, 57 WM. & MARY L. REV. 1, 33 (2015); Richard Collin Mangrum, Comment on the Proposed Revision of Federal Rule 702: “Clarifying” the Court’s Gatekeeping Responsibility over Expert Testimony, 56 CREIGHTON LAW REVIEW 97, 106 & n.45 (2022); Thomas D. Schroeder, Toward a More Apparent Approach to Considering the Admission of Expert Testimony, 95 NOTRE DAME L. REV. 2039, 2045 (2020); Lawrence A. Kogan, Weight of the Evidence: A Lower Expert Evidence Standard Metastasizes in Federal Court, Washington Legal Foundation Critical Legal Issues WORKING PAPER Series no. 215 (Mar. 2020); Note, Judicial Conference Amends Rule 702. — Federal Rule of Evidence 702, 138 HARV. L. REV. 899, 903 (2025); Nathan A. Schachtman, Desultory Thoughts on Milward v. Acuity Specialty Products, DOI: 10.13140/RG.2.1.5011.5285 (Oct. 2015), available at https://www.researchgate.net/publication/282816421_Desultory_Thoughts_on_Milward_v_Acuity_Specialty_Products .
