States Slow to Adopt Daubert Evidence Rule

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By Bruce Kaufman

April 21 — More than two decades after the U.S. Supreme Court adopted the Daubert test for evaluating the reliability of scientific evidence in federal courtrooms, nearly a quarter of the states have retained their own standards.

In many of the holdout jurisdictions—including California, New York, New Jersey, Illinois, Maryland, Washington and the District of Columbia—the standard for admitting expert evidence in courtrooms closely follows the century-old Frye test, which was developed for evaluating then-novel polygraph testimony.

That test, which comes from Frye v. United States, 293 F. 1013 (D.C. Cir. 1923), asks whether “novel” expert opinions are based on techniques that are “generally accepted” as reliable in the relevant scientific field.

Over the last 20 years, most states have gravitated toward the broader standards set forth in Daubert v. Merrell Dow Pharms, 509 U.S. 579 (1993), either through legislation or judicial rulings.

The Daubert test requires trial judges to ensure that all scientific testimony, not just novel proof, is the product of a sound methodology before being admitted for trial.

A few states, including Virginia, Missouri, Nevada and North Dakota are hybrid jurisdictions and not easily categorized. Virginia, for example, seems to view the Daubert standards as instructive, but refuses to adopt them.

Is Daubert the Best Approach?

Unlike Frye, the Daubert standard is a judicial distillation of a key evidentiary tenet—Rule 702 of the Federal Rules of Evidence—and has continued to evolve through a series of Supreme Court rulings.

Daubert's relative freshness would seem to offer trial courts the most cutting-edge guidance in keeping questionable evidence from juries in high-stakes litigation.

But is Daubert the best approach at the state level?

And are the practicalities of courtroom challenges to experts in Frye states likely to differ meaningfully from those in Daubert jurisdictions?

Interviews with leading litigators and law professors, all seasoned experts in evidence law, offer a mixed bag.

Deciding What is `Good Science.'

Paul Rothstein, a professor at Georgetown Law School and author of “Federal Rules of Evidence, 3d” (2015), wasn't taken aback that more states haven't shifted to the Daubert standards.

“Judges do not feel competent to decide what is good science, as Daubert commands them to do,” Rothstein told Bloomberg BNA.

Rothstein said that states may also be reluctant to switch over to Daubert because it “hasn't worked out very well in federal courts.”

The criteria Daubert sets out—testability/testing, peer review, low error rate, professional standards, acceptability in the discipline, all leading to reliability—are “so spongy that the cases come out all over the place,” he said.

Rothstein said a key failure of Daubert is there is no specification of the “required DEGREE of reliability” or of any of the criteria, nor of priorities amongst them. “Nor do they purport to be definitive or exclusive; nor is there anything about how general or specific a judge is to be in selecting the principles to which the criteria apply,” Rothstein said.

The Daubert opinion forces us to ask: “How reliable is reliable?” But the answer is “left open,” Rothstein said.

Since the decision itself also emphasizes “flexibility,” the Daubert admissibility rulings around the country are “subjective and not at all uniform,” he said.

As a result, civil and criminal trial lawyers often can't predict results, he said. And they can't counsel their clients about outcomes with any degree of certainty.

“Civil clients can't estimate in advance whether the chances of success justify spending the money to litigate a case or not,” Rothstein said.

To the extent one can see any pattern in outcomes, Daubert seems to be applied by judges more rigorously against plaintiffs in civil cases than against prosecutors in criminal cases, he said.

Daniel J. Capra, a professor at Fordham Law School in New York, told Bloomberg BNA that, in civil cases, the Daubert rules are worthwhile because the parties tend to be well funded and can better absorb the added cost of so-called mini-trials over evidentiary disputes.

But in criminal cases, the Frye approach works well enough, he said, and doesn't call out for change.

What Litigators Need to Tell Experts

In preparing for trial in a court that rigorously applies Daubert, Rothstein said litigators need to advise their expert witnesses to do much more than merely say their techniques and the principles they employed are accepted in the relevant field, in order to lay a foundation for the admissibility of their testimony.

“The expert must be prepared to articulate how he/she applied particularly defined scientific principles to facts, in a logical and scientific way, to arrive at specific conclusions, and how alternative hypotheses were considered and rejected and why,” he said.

“There must not be too great and unexplained a leap from data to conclusions,” Rothstein said.

“The conclusions must not seem to be `ipse dixit' (`It is so because I say it is so').”

And, where possible, “it is best not to justify a conclusion merely by referring to the expert's generally expressed `experience,' ” he said.

Practical Differences Spelled Out

Rothstein cited other differences between Daubert and Frye.

Frye tends to keep out evidence firmly-based on sound scientific principles if the evidence or the science is new,” meaning no established track record or general acceptance within its field exists, he said.

On this standard, “which is extremely conservative and pays obeisance to establishment science, Galileo would have been rejected (as he was),” Rothstein said.

By comparison, “Daubert can be read to say that if the science is good, the evidence comes in, even if it has no track record and even if the establishment does not recognize it,” he said.

Additionally, some courts say Daubert mandates judicial scrutiny not only of whether the expert's scientific principles are sound, but also whether they were properly applied.

Frye, at least under some court interpretations, “normally makes proper application or proper protocols only a matter of weight for the fact-finder, not a matter of admissibility,” he said.

Finally, Daubert may result in “more reliable science” than Frye, he said.

The National Research Council and some scientific organizations have been stimulated by the scientific reliability language in Daubert, to undertake studies of various forensic techniques with a view to making them more scientific, Rothstein said.

Uncertain Trend Toward Uniform Standards

Are states moving toward uniform standards, especially in evidentiary law?

Jeffrey Bellin, a professor at William & Mary Law School in Williamsburg, Va., said he sees such a trend.

And Bellin, author of “The Virginia and Federal Rules of Evidence: A Concise Comparison with Commentary” (2015), predicted that trend “will likely continue” because “consistency across jurisdictions is a benefit, particularly for litigators.”

Capra, who serves as the reporter on the Judicial Conference Advisory Committee on the Federal Rules of Evidence, says most states have already adopted analogs to the federal rules of evidence. But he doesn't see an aggressive shift in the formal adoption of Daubert by states.

In Frye states, such as New York, many courts already pay homage to Daubert in their own way, a process referred to as “Daubert creep,” Capra said.

Douglas G. Smith a partner at Kirkland & Ellis in Washington, told Bloomberg BNA it's “unlikely that there will ever be a uniform set of standards for evaluating the admissibility of expert evidence, given that the standards are largely the result of judicial creation.”

Moreover, the “need for any such uniform body of rules is not particularly acute given that courts frequently look to other jurisdictions in deciding cases involving the admissibility of expert evidence,” he said.

Rothstein said that eventually “we will have something that is a mixture of Daubert and Frye everywhere.”

That mix is gradually coming to pass in a few states now, he said. But for the foreseeable future the mix will be applied “differently and inconsistently by different judges,” he said.

Rothstein also said there was no need for a single unified solution covering all scientific evidence.

“I do think rules will begin to emerge about particular kinds of scientific evidence, and the rules eventually will be widely subscribed-to by most jurisdictions via a process of cross-fertilization,” he said.

“It will come about by repeated interpreting and refining, in specific factual contexts, of whatever general test for the overall admissibility of scientific evidence the jurisdiction might have. Patterns specifically tailored to a specific kind of case and kind of evidence will emerge,” he said.

Rothstein got out his crystal ball and offered several examples.

“There will be a rule about what kind of evidence is and is not receivable (and sufficient) to prove causation in a toxic tort case,” he said.

And admissibility rules about various kinds of physician testimony in “more mundane medical cases will probably evolve, and the standard arrived at will (if current cases applying Daubert and Frye to physicians are any guide) be lower than in strictly scientific cases.”

“Although some patterns like this are already beginning to emerge, it will in all likelihood be a long time before a system of definitive rules will fully develop, if ever,” Rothstein said.

To contact the reporter on this story: Bruce Kaufman in Washington at

To contact the editor responsible for this story: Jeffrey D. Koelemay at

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