Our Stolen Futurea book by Theo Colborn, Dianne Dumanoski, and John Peterson Myers


Chemical and Engineering News
7 July 2003

Daubert rules challenge courts.
Critics argue that 1993 decision on scientific evidence denies justice, compromises science

Bette Hileman, C&EN, Washington.

Ten years ago, on June 28, 1993, the U.S. Supreme Court issued an opinion that laid out specific guidelines for determining what scientific evidence is admissible in court. The guidelines established by Daubert v. Merrell Dow Pharmaceuticals Inc. came to be known as Daubert standards. In its decision, the high court instructed federal judges to act as "gatekeepers" in the courtroom, applying standards that require expert testimony to be both reliable and relevant before it is allowed to be presented to a jury.

Under the ruling, evidence presented in court by scientific experts must be based on a testable peer-reviewed theory with a known error rate and must be generally accepted by the scientific community. The Supreme Court cautioned, however, that these criteria are not to be used as a checklist on each component of the evidence.

At the time, the Daubert standards sounded reasonable to most observers. Almost no one was in favor of allowing scientific testimony in the courtroom that is based on pure speculation and universally rejected by experts in the field.

But, critics now say, what started as an attempt to improve the quality of scientific evidence in the courtroom has had unanticipated consequences. They say that Daubert standards have resulted in the exclusion of critical data, thereby compromising justice. Some judges have misinterpreted Daubert; others have thrown out all the evidence when the scientific experts in the case seem to disagree. Also, critics argue, judges look at the strength of each individual component of the evidence and exclude those components that appear weak, rather than assessing the evidence as a whole, as scientists do.

Moreover, a few judges have made the Daubert standards even stricter than the Supreme Court intended. As a result of these developments, critics say, judges have dismissed many meritorious cases with summary judgments.

The Daubert opinion "has resulted in a concerted campaign to manufacture uncertainty about scientific evidence," says David M. Michaels, professor in the department of occupational and environmental health at George Washington University School of Public Health. Since this ruling, much more science-based evidence has been excluded from civil cases than was previously, he contends.

"Often, there is only one expert witness who is willing to testify, and if you strike that one out, the plaintiff's case just crumbles."

BEFORE THE DAUBERT ruling, juries played a large role in assessing the validity of scientific testimony. The plaintiff's lawyer and experts presented their side, and the defense cross-examined them. The jury then decided which side had stronger, more legally defensible, arguments. Usually, judges did not exclude expert witnesses before cases went to trial. Even when they considered the evidence to be presented by the witnesses somewhat weak, judges usually let the cases go forward and allowed the juries to decide on the merits of the evidence.

Now, in tort law cases--personal injury law--scientific experts are often excluded, greatly reducing the plaintiff's chances of winning the case. In some instances, this means that time is saved and frivolous cases do not go to trial. But in other instances, Daubert standards are called into play, and plantiffs who claim to have been harmed by a chemical may not be able to present their case to a jury.

"After the expert is knocked out, the plaintiff, of course, can't show causation," says Margaret A. Berger, a law professor at Brooklyn Law School. "So the judge will grant summary judgment for the defendant. And that is the end of the case."

Don Evans, senior counsel at the American Chemistry Council, explains it this way: "Often, there is only one expert witness who is willing to testify, and if you strike that one out, the plaintiff's case just crumbles. Your day in court is basically stripped."

According to a study by the RAND Institute for Civil Justice, the percentage of summary judgments granted after the Daubert decision more than doubled, and 90% of the judgments favored the defendant.

Although the Daubert decision applies only to federal courts, many state supreme courts have adopted criteria similar to the Daubert standards. "The great majority are moving toward tightening the rules of admissibility of scientific evidence," Evans says. Berger adds that even those states that have not formally adopted Daubert "screen their expert witnesses in a way they didn't before Daubert."

Furthermore, some states have adopted standards that are stricter than Daubert. Texas, for instance, now requires that a substance must cause at least a doubling of an adverse effect to prove causation. For example, if exposure to a chemical does not raise the cancer rate at least 100% over the rate in the general population, it is not considered a factor that could have induced cancer in a particular plaintiff. This is a much stricter standard than those used by federal agencies in risk assessments and one that has been criticized even by lawyers who defend industry. A less than twofold risk increase is widely accepted as causal. Mark P. Fitzsimmons, an attorney at Steptoe & Johnson, says the Texas ruling may be excessive. "A lot of people, including defense lawyers, say that is arguably an overinterpretation of the standard," he says.

BUT STATE COURTS have not responded uniformly to Daubert. A few have weakened their standards for admissibility of evidence. "There are some places that have been a failure. Illinois just leaps out at you. It has gone in the wrong direction and liberalized its standards over the years," Evans says. "Madison County, Ill., is one of the hell holes of the legal system. There, it is practically impossible to challenge speculative evidence," he explains.

The major problem with Daubert is that assessing scientific evidence is "incredibly complicated," and Daubert somehow suggests that "there can be a formula for answering these questions," Berger says. "To say that science has the tools for a precise understanding of causation is probably unrealistic," she explains. "We are at the threshold of understanding the interaction of genetics and environment and all kinds of other possible factors. To hinge everything on a very mechanical interpretation of causation seems to me unfair to plaintiffs," she says.

"There is no way plaintiffs have the information to decide these kinds of issues. The defendants have a much better sense of how to do research, what research is relevant, and what research has been done," Berger notes. "Plaintiffs have a tremendous burden, and Daubert has exacerbated that. To keep industries from going bankrupt because of unfounded claims, you don't have to swing so far" in the direction of placing additional burdens on plaintiffs, she says.

To improve the situation, Berger says, judges need to realize that the science of causation is complicated and "that applying Daubert in such a rigid way has negative policy implications." Also, "they need to be much more open to looking at a variety of different kinds of evidence," she says. They should look at the totality of studies rather than examining them piece by piece and knocking out each component individually if it appears deficient in any way, she says.

For example, some judges eliminate animal studies from consideration if the administered dose of a chemical is greater than what humans are exposed to. Yet federal agencies and pharmaceutical firms use such research all the time to help understand toxic effects. Also, judges exclude epidemiological studies if they are weak in any way, Berger says.

"Deciding which expert or study is more reliable is not supposed to be part of the judge's role," says Stanley Feldman, former Chief Justice of the Arizona Supreme Court. "To allow the trial judge to make these decisions just violates the essential core of one's right to a jury trial."

The biggest change resulting from the Daubert decision is that litigation has become "astronomically expensive" because of the added cost of Daubert hearings, Berger says. This has discouraged plaintiff's attorneys from taking cases that rely on complex scientific evidence unless the potential monetary damages are enormous, she says.

Peter F. Infante, a fellow of the American College of Epidemiology and former director of the Occupational Safety & Health Administration's Office of Standards Review, cites a case in which he believes legitimate science was kept out of the courtroom. He was prevented from testifying in Chambers v. Exxon Corp., a lawsuit involving a contractor at an oil refinery in Baton Rouge, La. After exposure to benzene, the contractor developed chronic myelogenous leukemia (CML), a rare form of cancer.

Previously, Infante had conducted a study that found a fourfold increase in CML risk from benzene exposure. But the judge excluded Infante's testimony, saying it wasn't strong enough, and issued a summary judgment in favor of the defendant. "It seems to me the judge was making a scientific determination when he did not have the expertise to do that," Infante says.

In Hollander v. Sandoz Pharmaceuticals Corp., a case involving the lactation suppressor Parlodel, the judge excluded animal studies and case reports as unreliable. He said the results of animal studies could not be extrapolated to humans. Case studies are unreliable, he said, because they "do not eliminate confounding variables." But scientists routinely use both types of research in risk assessments.

THE RAND STUDY confirms that judges are applying a very strict standard to scientific evidence. They are excluding evidence if it fails to meet even a single one of the Daubert standards, even though the Supreme Court ruling warned judges not to use the criteria as a checklist.

Evans says it is understandable that courts may use a stricter standard for the admissibility of scientific evidence than regulators at the Food & Drug Administration or the Environmental Protection Agency. FDA regulators act for preventive public health purposes, he says. "They see some things that bother them, like adverse effects from a drug, and move fast to do something for a public health purpose," he explains.

Richard O. Faulk, an attorney at the Texas firm Gardere Wynne Sewell, agrees. "There is a huge difference between what goes on in regulatory agencies and in the courts," he says. "Regulatory agencies are supposed to take the most conservative evaluation possible that will protect the maximum number of people," he says. In courts, "we're charged with the responsibility of determining as a matter of fact whether or not it is more likely that a substance causes a particular disease in a particular person. That is a totally different inquiry," he explains.

Evans also claims that if an expert uses sound science and methods and explains all of the evidence to a judge, the judge will look at the totality of the evidence rather than striking it down piece by piece. He considers Daubert a neutral ruling that simply requires the scientific rigor of expert testimony "to be equal to what's outside the courtroom." Lawyers have a role to play in the application of Daubert, he says. "It is their duty to make sure the judges have all the information necessary to assess the reliability of the evidence," he says.

In contrast, Faulk, who defends petrochemical firms, does not believe courts should take a weight-of-evidence approach to the evaluation of scientific evidence. This "approach has no relevance whatsoever to toxic tort cases," he says. In court, "the key is that each of the pieces of scientific evidence has to be sufficient in and of itself to illustrate the point that people are trying to prove," he contends.

Faulk points out that it is "fundamentally unfair to criticize the Daubert principle on the basis of any isolated or individual applications of it. Sometimes it is applied correctly and sometimes not," he says. "The rule has done an impressive job so far in making sure that reliable science is a part of the judicial process," he explains. He believes that judges should screen scientific evidence because juries have no tools with which to judge unreliable scientific evidence and "have to take it at face value."

It is hard to say what Daubert's future will be. It seems unlikely that the moderately conservative Supreme Court would overturn it in the near future. There is certainly a great deal of interest in the topic among the legal profession. Over the past decade, hundreds of articles have been written in law reviews and scholarly journals about the pros and cons of Daubert. Many legal scholars and lawyers consider the judicial trends since Daubert largely negative, but others say that it has had net positive benefits.



The Daubert Supreme Court decision suggests four questions that judges should consider in determining whether an area or field of science is reliable enough to be used in the courtroom. The decision says this list should not be regarded by judges as "a definitive checklist or test," opening the door for judges to employ criteria of their own.

Is the evidence based on a testable theory or technique?

Has the theory or technique been peer reviewed?

Does the technique have a known error rate and standards controlling its operation?

Is the underlying science generally accepted?



Three Decisions Together Are Used To Assess Scientific Testimony

* Daubert v. Merrell Dow Pharmaceuticals Inc. This 1993 case establishes new guidelines for admissibility of scientific evidence in federal courts. It tells judges they must be gatekeepers and determine what is reliable evidence and what is not. The guidelines replaced evidence rules established in 1923 by the case Frye v. U.S., which states that expert testimony must simply be generally accepted by practitioners of the particular field.
* General Electric v. Joiner. This 1997 case expands the trial court's gatekeeper role. Trial courts are called upon to assess not only "scientific" testimony, but all testimony that can be described as "scientific, technical, or other specialized knowledge." It says the trial court's scrutiny is not limited to methodology, but can extend to the expert's analysis. It states, "A court may conclude that there is simply too great an analytical gap between the data and the opinion proffered."
* Kumho Tire v. Carmichael. This 1999 case stipulates that the trial judge's gatekeeper role is to be exercised for all expert witness testimony. It says that the gatekeeper obligation is intended to ensure that technical and all other expert testimony is both relevant and based upon a reliable foundation prior to its admission. It establishes that a trial judge is vested with broad authority to determine whether and to what extent the enumerated Daubert factors are applicable to a case.





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