For your delectation and delight, desultory dicta on the law of delicts.

New-Age Levellers – Flattening Hierarchy of Evidence

October 30th, 2011

The Levelers were political dissidents in England, in the middle of the 17th century.  Among their causes, Levelers advanced popular sovereignty, equal protection of the law, and religious tolerance.

The political agenda of the Levelers sounds quite noble to 21st century Americans, but their ideals have no place in the world of science:  not all opinions or scientific studies are created equally; not all opinions are worthy of being taken seriously in scientific discourse or in courtroom presentations of science; and not all opinions should be tolerated, especially when they claim causal conclusions based upon shoddy or inadequate evidence.

In some litigations, legal counsel set out to obscure the important quantitative and qualitative distinctions among scientific studies.  Sometimes, lawyers find cooperative expert witnesses, willing to engage in hand waving about “the weight of the evidence,” where the weights are assigned post hoc, in a highly biased fashion.  No study (that favors the claim) left behind.  This is not science, and it is not how science operates, even though some expert witnesses, such as Professor Cranor in the Milward case, have been able to pass off their views as representative of scientific practice.

A sound appreciation of how scientists evaluate studies, and of why not all studies are equal, is essential to any educated evaluation of scientific controversies.  Litigants who face high-quality studies, with results inconsistent with their litigation claims, may well resort to “leveling” of studies.  This leveling may be advanced out of ignorance, but more likely the leveling is an attempt to snooker courts with evidence from exploratory, preliminary, and hypothesis-generating studies as somehow equal to, or greater than, the value of hypothesis-testing studies.

Some of the leveling tactics that have become commonplace in litigation include asserting that:

  • All experts witnesses are the same;
  • All expert witnesses conduct the same analysis;
  • All expert witnesses read articles, interpret them, and offer opinions;
  • All expert witnesses are inherently biased;
  • All expert witnesses select the articles to read and interpret in line with their biases;
  • All epidemiologic studies are the same;
  • All studies are flawed; and
  • All opinions are, in the final analysis, subjective.

This leveling strategy can be seen in Professor Margaret Berger’s introduction to the Reference Manual on Scientific Evidence (RMSE 3d), where she supported an ill-defined “weight-of-the-evidence” approach to causal judgments. SeeLate Professor Berger’s Introduction to the Reference Manual on Scientific Evidence” (Oct. 23, 2011).

Other chapters in the RMSE 3d are at odds with Berger’s introduction.  The epidemiology chapter does not explicitly address the hierarchy of studies, but it does describe cross-sectional, ecological, and secular trend studies are less able to support causal conclusions.  Cross-sectional studies are described as “rarely useful in identifying toxic agents,” RMSE 3d at 556, and as “used infrequently when the exposure of interest is an environmental toxic agent,” RMSE 3d at 561.  Cross-sectional studies are described as hypothesis-generating as opposed to hypothesis testing, although not in those specific terms.  Id. (describing cross-sectional studies as providing valuable leads for future research).  Ecological studies are described as useful for identifying associations, but not helpful in determining whether such associations are causal; and ecological studies are identified as a fertile source of error in the form of the “ecological fallacy.”  Id. at 561 -62.

The epidemiology chapter perhaps weakens its helpful description of the limited role of ecological studies by citing, with apparent approval, a district court that blinked at its gatekeeping responsibility to ensure that testifying expert witnesses did, in fact, rely upon “sufficient facts or data,” as well as upon studies that are “of a type reasonably relied upon by experts in the particular field in forming opinions or inferences upon the subject.” Rule 703. RMSE 3d at 561 n.34 (citing Cook v. Rockwell International Corp., 580 F. Supp. 2d 1071, 1095–96 (D. Colo. 2006), where the district court acknowledged the severe limitations of ecological studies in supporting causal inferences, but opined that the limitations went to the weight of the study). Of course, the insubstantial weight of an ecological study is precisely what may result in the study’s failure to support a causal claim.

The ray of clarity in the epidemiology chapter about the hierarchical nature of studies is muddled by an attempt to level epidemiology and toxicology.  The chapter suggests that there is no hierarchy of disciplines (as opposed to studies within a discipline).  RMSE 3d at 564 & n.48 (citing and quoting symposium paper that “[t]here should be no hierarchy [among different types of scientific methods to determine cancer causation]. Epidemiology, animal, tissue culture and molecular pathology should be seen as integrating evidences in the determination of human carcinogenicity.” Michele Carbone et al., “Modern Criteria to Establish Human Cancer Etiology,” 64 Cancer Res. 5518, 5522 (2004).)  Carbone, of course, is best known for his advocacy of a viral cause (SV40), of human mesothelioma, a claim unsupported, and indeed contradicted, by epidemiologic studies.  His statement does not support the chapter’s leveling of epidemiology and toxicology, and Carbone is, in any event, an unlikely source to cite.

The epidemiology chapter undermines its own description of the role of study design in evaluating causality by pejoratively asserting that most epidemiologic studies are “flawed”:

“It is important to emphasize that all studies have ‘flaws’ in the sense of limitations that add uncertainty about the proper interpretation of the results.9 Some flaws are inevitable given the limits of technology, resources, the ability and willingness of persons to participate in a study, and ethical constraints. In evaluating epidemiologic evidence, the key questions, then, are the extent to which a study’s limitations compromise its findings and permit inferences about causation.”

RSME 3d at 553.  This statement is actually a significant improvement over the second edition, where the authors of the epidemiology chapter asserted, without qualification:

“It is important to emphasize that most studies have flaws.”

RMSE 2d 337.  The “flaws” language from the earlier chapter was used on occasion by courts that were set on ignoring competing interpretations of epidemiologic studies.  Since all or most studies are flawed, why bother figuring out what is valid and reliable?  Just let the jury sort it out.  This is not an aid to gatekeeping, but rather a prescription for allowing the gatekeeper to call in sick.

The current epidemiology chapter essentially backtracks from the harsh connotations of its use of the term “flaws,” by now equating the term with “limitations.”  Flaws and limitations, however, are quite different from one another.  What is left out in the third edition’s description is the sense that there are indeed some studies that are so flawed that they must be disregarded altogether.  There may also be limitations in studies, especially observational studies, which is why the party with the burden of proof should generally not be allowed to proceed with only one or two epidemiologic studies.  Rule 702, after all, requires that an expert opinion to be based upon “sufficient facts or data.”

The RSME 3d chapter on medical evidence is a refreshing break from the leveling approach seen elsewhere.  Here at least, the chapter authors devote several pages to explaining the role of study design in assessing an etiological issue:

3. Hierarchy of medical evidence

With the explosion of available medical evidence, increased emphasis has been placed on assembling, evaluating, and interpreting medical research evidence.  A fundamental principle of evidence-based medicine (see also Section IV.C.5, infra) is that the strength of medical evidence supporting a therapy or strategy is hierarchical.

When ordered from strongest to weakest, systematic review of randomized trials (meta-analysis) is at the top, followed by single randomized trials, systematic reviews of observational studies, single observational studies, physiological studies, and unsystematic clinical observations.150 An analysis of the frequency with which various study designs are cited by others provides empirical evidence supporting the influence of meta-analysis followed by randomized controlled trials in the medical evidence hierarchy.151 Although they are at the bottom of the evidence hierarchy, unsystematic clinical observations or case reports may be the first signals of adverse events or associations that are later confirmed with larger or controlled epidemiological studies (e.g., aplastic anemia caused by chloramphenicol,152 or lung cancer caused by asbestos153). Nonetheless, subsequent studies may not confirm initial reports (e.g., the putative association between coffee consumption and pancreatic cancer).154

John B. Wong, Lawrence O. Gostin, and Oscar A. Cabrera, “Reference Guide on Medical Testimony,” RMSE 3d 687, 723 -24 (2011).  The third edition’s chapter is a significant improvement of the second edition’s chapter on medical testimony, which does not mention the hierarchy of evidence.  Mary Sue Henifin, Howard M. Kipen, and Susan R. Poulter, ” Reference Guide on Medical Testimony,” RMSE 2d 440 (2000).  Indeed, the only time the word “hierarchy” appeared in the entire second edition was in connection with the hierarchy of the federal judiciary.

The tension, contradictions, and differing emphases among the various chapters of the RSME 3d point to an important “flaw” in the new edition.  The chapters appear to have been written largely in isolation, and without much regard for what the other chapters contain.  The chapters overlap, and indeed contradict one another on key points.  Witness Berger’s rejection of the hierarchy of evidence, the epidemiology chapter’s inconstant presentation of the concept without mentioning it by name, and the medical testimony chapter’s embrace and explicit presentation of the hierarchical nature of medical study evidence.  Fortunately, the laissez-faire editorial approach allowed the disagreement to remain, without censoring any position, but the federal judiciary is not aided by the contradiction and tension in the approaches.

Given the importance of the concept, even the medical testimony chapter in RSME 3d may seem to be too little, too late to be helpful to the judiciary.  There are book-length treatments of systematic reviews and “evidence-based medicine”: the three pages in Wong’s chapter barely scratch the surface of this important topic of how evidence is categorized, evaluated, and synthesized in making judgments of causality.

There are many textbooks and articles available to judges and lawyers on how to assess medical studies.  Recently, John Cherrie has posted on his blog, OH-world, about a series of 17 articles, in the journal Aerzteblatt International, on the proper evaluation of medical and epidemiologic studies.

These papers, overall, make the point that not all studies are equal, and that not all evidentiary displays are adequate to support conclusions of causal association.  The papers are available without charge from the journal’s website:

01. Critical Appraisal of Scientific Articles

02. Study Design in Medical Research

03. Types of Study in Medical Research

04. Confidence Interval or P-Value?

05. Requirements and Assessment of Laboratory Tests: Inpatient Admission Screening

06. Systematic Literature Reviews and Meta-Analyses

07. The Specification of Statistical Measures and Their Presentation in Tables and Graphs

08. Avoiding Bias in Observational Studies

09. Interpreting Results in 2×2 Tables

10. Judging a Plethora of p-Values: How to Contend With the Problem of Multiple Testing

11. Data Analysis of Epidemiological Studies

12. Choosing statistical tests

13. Sample size calculation in clinical trials

14. Linear regression analysis

15. Survival analysis

16. Concordance analysis

17. Randomized controlled trials

This year, the Journal of Clinical Epidemiology began publishing a series of papers, known by the acronym GRADE, which aim to provide guidance on how studies are categorized and assessed for their evidential quality in supporting treatments and intervention.  The GRADE project is led by Gordon Guyatt, who is known for having coined the term “evidence-based medicine,” and written widely on the subject.  Guyatt, along with his colleagues including Peter Tugwell (who was one of the court-appointed expert witnesses in MDL 926), has described the GRADE project:

“The ‘Grades of Recommendation, Assessment, Development, and Evaluation’ (GRADE) approach provides guidance for rating quality of evidence and grading strength of recommendations in health care. It has important implications for those summarizing evidence for systematic reviews, health technology assessment, and clinical practice guidelines. GRADE provides a systematic and transparent framework for clarifying questions, determining the outcomes of interest, summarizing the evidence that addresses a question, and moving from the evidence to a recommendation or decision. Wide dissemination and use of the GRADE approach, with endorsement from more than 50 organizations worldwide, many highly influential, attests to the importance of this work. This article introduces a 20-part series providing guidance for the use of GRADE methodology that will appear in the Journal of Clinical Epidemiology.”

Gordon Guyatt, Andrew D. Oxman, Holger Schünemann, Peter Tugwell, Andre Knottnerus, “GRADE guidelines – new series of articles in Journal of Clinical Epidemiology,” 64 J. Clin. Epidem. 380 (2011).  See also Gordon Guyatt, Andrew Oxman, et al., for the GRADE Working Group, “Rating quality of evidence and strength of recommendations GRADE: an emerging consensus on rating quality of evidence and strength of recommendations,” 336 Brit. Med. J. 924 (2008).  [pdf]

Of the 20 papers planned, 9 of the GRADE papers have been published to date in the Journal of Clinical Epidemiology:

01 Intro – GRADE evidence profiles & summary of findings tables

02 Framing question & deciding on important outcomes

03 Rating quality of evidence

04 Rating quality of evidence – study limitations (risk of bias)

05 Rating the quality of evidence—publication bias

06 Rating up quality of evidence – imprecision

07 Rating quality of evidence – inconsistency

08 Rating quality of evidence – indirectness

09 Rating up quality of evidence

The GRADE guidance papers focus on the efficacy of treatments and interventions, but in doing so, they evaluate “effects” and are thus applicable to the etiologic issues of alleged harm that find their way into court.  The papers build on other grading systems advanced previously by the Oxford Center for Evidence-Based Medicine, the U.S. Preventive Services Task Force (Agency for Healthcare Research and Quality AHRQ), the Cochrane Collaboration, as well as many individual professional organizations.

GRADE has had some success in harmonizing disparate grading systems, and forging a consensus among organizations that had been using their own systems, such as the  World Health Organization, the American College of Physicians, the American Thoracic Society, the Cochrane Collaboration, the American College of Chest Physicians, the British Medical Journal, and Kaiser Permanente.

There are many other important efforts to provide consensus support for improving the quality of the design, conduct, and reporting of published studies, as well as the interpretation of those studies once published.  Although the RSME 3d does a good job of introducing its readers to the basics of study design, it could have done considerably more to help judges become discerning critics of scientific studies and of conclusions based upon individual or multiple studies.

Historians As Expert Witnesses – A Wiki

October 28th, 2011

“The one duty we owe to history is to rewrite it.”

Oscar Wilde, The Critic As Artist (1891)

“What will history say?  History, sir, will tell lies as usual.”

George Bernard Shaw, The Devil’s Disciple (1901)

* * * * * * * * * * * * * * * * * * * * * * * * *

The Defense Research Institute recently announced that Bill Childs, a professor at the Western New England University School of Law, will be speaking the use of historians as expert witnesses in litigation.  Having puzzled about this very issue in previous writings, I look forward to Professor Childs’ contributions on the issue.  The announcement also noted Professor Childs’ creation, “the Historians as Experts Wiki,” which I knew about, but had not previously visited.

The wiki is a valuable resource of information about historians who have participated in the litigation process in all manner of cases, including art, asbestos, creationism, native Americans, holocaust, products liability, intellectual property, and voting rights.  There are pages for each historian witness, including expert witnesses in other fields, who have given testimony of an explicitly historical nature. The website is still in its formative stages, but it holds great promise as a resource to lawyers who are researching historians who have been listed as expert witnesses in their cases.

Most of my musings about historians as expert witnesses have been provoked by those who have testified about the history of silicosis.  Last year, I presented at a conference sponsored by the International Commission on Occupational Health (ICOH), about such historians.  See “A Walk on the Wild Side,” July 16, 2010.  My presentation abstract, along with all the proceedings of that conference, will be published next year as  “Courting Clio:  Historians and Their Testimony in Products Liability Action,” in: Brian Dolan and Paul Blanc, eds., At Work in the World: Proceedings of the Fourth International Conference on the History of Occupational and Environmental Health, Perspectives in Medical Humanities, University of California Medical Humanities Consortium, University of California Press (2012)(in press).

Philadelphia Courts – Structural Bias and Reverse Bifurcation

October 27th, 2011

When I studied federal courts in law school, some of the most interesting cases involving federal diversity and removal jurisdiction were decisions of the Third Circuit, on appeals from the Eastern District of Pennsylvania.  At the time, it did not occur to me that there must be strong incentives to push the boundaries of federal jurisdiction so hard to avoid state court.  A few years later, when I started to try cases in the Philadelphia County Court of Common Pleas, I “got it.”

You probably do not need to have a doctorate in economics to object when someone pisses on you, and calls it rain.  Still, it is comforting to have corroboration from someone with a doctorate.

Joshua D. Wright, a professor of law and economics at George Mason University School of Law, has written up the results of a study, “Are Plaintiffs Drawn to Philadelphia’s Civil Courts? An Empirical Examination,” published by the International Center for Law & Economics.  Professor Wright finds that the Philadelphia civil court system contains significant structural biases, which makes the Philadelphia Court of Common Pleas (PCCP) a magnet for plaintiffs from around the country, and which inflates verdicts and settlements in civil cases.

One such structural bias is the existence of a Complex Litigation Center.  Some of the judges and administrators in charge of the Center have seen their role to be rain makers, to bring litigation business to Philadelphia.  Of course, proper venue and the doctrine of forum non conveniens may tend to get in the way of such an official business plan.

Another structural bias in the Philadelphia courts is the automatic, unthinking use of a procedure called reverse bifurcation.  Typically bifurcation requires plaintiff to establish liability before proceeding to causation and damages, but reverse bifurcation puts causation and damages first.  This bizarre procedure was first urged by Johns-Manville lawyers in asbestos litigation, to avoid the shame and shock of having the jury hear their company’s liability case at the same time that the jury heard the evidence whether plaintiff was injury.  Reverse bifurcation gave them a chance to sanitize the trial on medical causation.  If they lost an up-or-down medical issue, the Johns-Manville lawyers could settle to avoid having the ugly liability evidence shared with the jury.

Johns-Manville soon filed for bankruptcy, but the plaintiffs’ bar learned that reverse bifurcation was a wonderful procedure.  They could get a verdict after three days of trial, and the second phase of the case was virtually untriable by the defense.  Why?  Because the plaintiffs’ lawyers found that they could inject their liability case surreptitiously into the first phase.  Claiming a relevancy to fear and emotional distress, plaintiffs’ counsel asked their clients whether they ever contemplated the horror of living with the increased risks of disease they now supposedly faced, and plaintiffs responded that they had no idea of the risks when they worked at the shipyards, refineries, or other workplaces.  In summation, plaintiffs’ counsel would slip in something like “After the last few days, you, members of the Jury, now know more about asbestos than my client did after 30 years of working in the shipyard.”  Defense objections and motions in limine were studiously ignored.  Who needs to prove a failure to warn, when you can simply assert it?

Egregiously, the reverse bifurcation procedure stuck, even when defendants, unlike Johns-Manville, had potent defenses.  Some Philadelphia judges, in second phase trials, tolerate indignant arguments from plaintiff’s counsel, to the effect that first the (recalcitrant) defendant caused this injury to his client, and now that defendant wants to take away plaintiff’s money, which the jury so thoughtfully, carefully, and justly awarded in the first phase.  Winning a second phase trial, in a case that has been reverse bifurcated, is a bit like cleaning out the Augean stables.

Some judges even went so far, in phase II liability trials as to sever crossclaims of the non-settling defendant.  This procedural maneuver required the defendant to post a bond for the entire judgment, without any offsets, in order to pursue an appeal.  The lack of a final judgment seemed not to disturb anyone other than the victimized defendant.

Not all Philadelphia judges were keen on these inequitable procedures.  I recall trying an asbestos case in front of Judge Levan Gordon, who refused to be bullied by the head of the Complex Litigation Center into reverse bifurcating asbestos trials.  (O’Donnell v. Celotex Corp., PCCP July Term 1982, No. 1619; May 1989)  Judge Gordon had his own strong medicine for defendants:  he tried the cases all issues, with no bifurcation of punitive damages.  Judge Gordon tried my case, which was prosecuted by now Philadelphia Judge Sandy Byrd, straight through.  Because my adversary, Sandy Byrd, insisted on pressing negligence and punitive damages, I was able to try an empty-chair defense against the United States government, which owned and ran the Philadelphia Naval Shipyard, where plaintiff worked.  I was also able to put on a state-of-the-art defense.  And my jury saw what juries rarely see in Philadelphia, the complete story.  They refused to hold my clients responsible for what really was the negligence of the government, even though I had a weak medical defense.

The head of the Complex Litigation Center was furious that Judge Gordon had taken up three weeks of courtroom time.  Her Honor was deaf to explanations that it was plaintiffs’ choice to pursue negligence and punitive damages, which claims opened the door to the sophisticated intermediary and state-of-the-art defenses.  Somehow it was the defendants’ fault for tying up a courtroom, and for derailing the all-important case statistics.

Then, as now, there are some excellent judges in Philadelphia, who are intent to try cases fairly and impartially, with even-handed procedures.  And then there are other judges, who have helped create Philadelphia’s reputation, and the statistics that support Professor Wright’s conclusions.

Manufacturing Certainty

October 25th, 2011

Steven Wodka is a plaintiffs’ lawyer, based in New Jersey, who has worked closely, for many years, with Dr. David Michaels, as his paid expert witness.  Yes, the David Michaels who is now the head of the Occupational Safety and Health Administration (OSHA).

When Michaels for nominated for his current post, the Democratic majority leaders in the Senate protected him from hearings, which would have revealed Michaels’ deep and disturbing conflicts of interest.  The Democratic Senators succeeded in their efforts, and Michaels was confirmed as undersecretary of the Department of Labor, on a voice vote, without hearings.

Mr. Wodka may have lost his friend, colleague, and expert witness to the OSHA, but at the same time he gained an ally in his litigation efforts on behalf of plaintiffs.  Wodka, who litigates in New Jersey and elsewhere, was troubled by court decisions that OSHA’s Hazard Communication regulations preempted his state-law tort claims. See, e.g., Bass v. Air Products, 2006 WL 1419375 (N.J. App. Div. 2006) (holding that OSHA’s hazard communication standard was a comprehensive regulatory scheme that preempted state tort failure-to-warn claims for warnings that complied with federal regulations).

Wodka may have lost his expert witness (for a while), but he gained an inside track to the Department of Labor.  Disappointed by New Jersey’s appellate court, Wodka sought an advisory opinion from the Department of Labor on the preemptive effect of HazCom.  See David Schwartz, “Solicitor Says Hazard Communication Rule Does Not Preempt Failure-to-Warn Lawsuits,” BNA (October 20, 2011).

The Department of Labor, now under control of his friend and paid expert witness, Dr. Michaels, did not disappoint.  Solicitor of Labor M. Patricia Smith, in a letter dated October 18, 2011, wrote Mr. Wodka that, notwithstanding what the appellate courts may have told him, he was correct after all.  The OSHA’s Hazard Commuication Standard, 29 C.F.R. 1200(a)(2), does not, according to the Department, preempt state tort claims alleging failures to warn.

The solicitor relied upon Section 4(b)(4) of the OSH Act, which states that nothing in the Act is intended to “enlarge or diminish or affect in any other manner the common law or statutory rights, duties or liabilities of employers and employees under any law with respect to injuries, diseases, or death arising out of, or in the course of, employment.”  The OSH Act, however, in making this disclaimer, was focused on the employer-employee relationship, with its attendant duties, rights, and obligations.  Failure-to-warn claims arise out of laws, whether statutory or common law, designed to protect consumers.  The solicitor’s analysis really misses the key point that a comprehensive scheme, such as the HazCom Act and regulations, applies to strangers to the employer-employee relationship, and constrains the nature and content of warnings communications to the employees of purchasers of chemical products and raw materials.

The solicitor was clear that “a definitive determination of conflict can only be made based on the particulars of each case.”  Smith Letter, at footnote 4.  This slight speedbump did not slow down Mr. Wodka, who was quoted by the BNA as saying that “[t]his letter makes the question clear,” and “I’m already going to move for reconsideration of one of my cases based on this letter.”

It is good to have friends in powerful places.

Of course, there is a good deal of irony involved in this story.  David Michaels has made a career out of scolding industry over conflicts of interest.  Michaels’ book, Doubt is Their Product, gets waved around in courtrooms, when defense expert witnesses testify that the plaintiffs’ evidence fails to show that a product causes harm, or has caused plaintiff’s harm.  Some people may find this scolding a little irritating, especially from someone, like Michaels, who fails to disclose his own significant conflicts of interest, from monies received as a testifying and consulting expert witness, and from running an organization,  The Project on Scientific Knowledge and Public Policy (SKAPP),  bankrolled by the plaintiffs’ counsel in the silicone gel breast implant litigation.

Doubt is not such a bad thing in the face of uncertain and inconclusive evidence.  We could use more doubt, and open-minded thought.  As Bertrand Russell wrote some years ago:

“The biggest cause of trouble in the world today is that the stupid people are so sure about things and the intelligent folks are so full of doubts.”