In making its first ruling on the proper use of scientific evidence in the courtroom, the U.S. Supreme Court has assured that a great many judges will be frantically playing catch-up on the basics of scientific method.
Yet, lawyers and scientists on all sides of the contentious debate over how much so-called "junk" science is finding its way to juries said Monday's decision, Daubert v. Merrell Dow Pharmaceuticals, was a thoughtful, fair and rational response to a messy and complex issue.
In a case involving a morning-sickness drug blamed for birth defects, the court ruled that federal judges must ensure that scientific evidence and testimony admitted in trials "is not only relevant, but reliable." The decision could have a vast and immediate effect on cases that rely in part on disputed scientific or technical matters, from the use of DNA fingerprinting and computerized ballistic analysis as evidence in criminal cases, to putative links between illness and chemical emissions from industrial plants in civil cases.
"This ruling could affect almost every piece of litigation in the federal courts from this point forward," said Paul Rothstein, professor of law at Georgetown University in Washington, D.C., who wrote a brief filed on behalf of the pharmaceutical company. "Today's world is so complicated that experts are used on almost every issue that comes to trial."
The court rejected the most rigid arguments from the defendant, that scientific testimony could be dismissed from a case just because it had not been previously published in scientific journals or was not widely accepted by mainstream scientists. But the justices insisted that this somewhat liberal allowance did not mean that the courts should serve as circuses for any crackpot scientific theory a self-described "expert" witness might care to offer.
The court said federal judges must assume strong responsibility for the quality of the scientific evidence presented in their courts, and they must look at the data under question to make sure scientific conventions were followed in generating the results. The justices suggested that federal judges must consider the basics of scientific method _ for example, whether a theory presented is subject to reproducible experimentation without being falsified, a hallmark of rigorous science.
Lawyers and scientists agreed that the ruling could swiftly improve the caliber of science in the courtroom, cutting down on the number of cases that rely on dubious scientific ground, that lawyers might have tried to ram through to litigation because they had an expert with a university degree willing to testify for them.
The ruling will also mean that a case cannot be dismissed simply because one side's expert witness is a scientific maverick whose name does not often appear in the prestigious pages of journals like The New England Journal of Medicine.
"I can't think of how the court could have come up with a better opinion," said Steven G. …