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Commentary By Peter W. Huber

Tires, Bees and Expertise

Do bumblebees always take off into the wind? Until recently, you might have called any old beekeeper to testify as an expert on that point, in federal courts from Florida to Michigan. “The beekeeper does not know any more about flight principles than the jurors,” two federal appellate courts had agreed. “But he has seen a lot more bumblebees than they have.”

Last week, however, a unanimous Supreme Court disagreed. The case, Kumho Tire Co. v. Carmichael actually concerned the testimony of a “tire failure expert”; the beekeepers had crept into the lower court’s opinion only for illustration. But with bees and tires alike, been-there-done-that isn’t enough to qualify you as an expert in federal court after all.

It was the fourth time in six years that the court has ruled on the use of expert testimony. Each time, fringe experts were sent packing. The first decision, in 1993, knocked out an epidemiologist who, alone in her profession, maintained that a morning-sickness drug caused birth defects. The second helped dispatch an expert who believed that small-cell lung cancer is promoted by exposure to PCBs. The third, an expert vouching for the reliability of polygraphs. Last week was the tire guy’s turn.

The Beekeeper Kind

The trial judge had concluded that Dennis Carlson’s views on tire failure didn’t meet the requirement of “reliability” set out in the Supreme Court’s 1993 opinion. But it didn’t have to, the appellate court had ruled. His expertise wasn’t “scientific”; it was more of the beekeeper kind. On matters pertaining to the flight of the bumblebee, an aeronautical engineer might qualify as an expert, too, but federal courts didn’t have to be that picky, not with “technical” experts. Yes they do, the Supreme Court unanimously concluded in last week’s ruling.

As a mechanical engineer with Michelin for 10 years, Mr. Carlson had surely seen a lot of tires. Yet, as Justice Stephen Breyer’s opinion noted, the analysis Carlson offered at trial didn’t sound like anything he’d have relied on at Michelin. He’d looked at some photographs of the failed tire, but hadn’t actually examined it until the morning of his deposition. A tire that failed must have been defective, he reasoned, if its remains didn’t show at least two specific signs of tire abuse. There had been two—the failed tire was worn bald, and had twice been repaired (inadequately) for punctures—but Mr. Carlson managed to discount them both. When pressed for detail on just how he knew there was a defect, he not only conceded but insisted that the “subjectiveness” of his analysis made it impossible to clarify things any further.

Explaining why such testimony was properly excluded, Justice Breyer’s opinion provides a short primer on tire “separation,” “overdeflection,” “bead groove,” tread wear and sidewall deterioration. You will find in his opinion helpful citations to the technical literature on rim flange abrasion and bead contact pressure measurements. Such papers, you will discover, are published under the auspices of the Society of Automotive Engineers and the Rubber Division of the American Chemical Society. You will also find something almost never seen before in a Supreme Court opinion on any subject: an illustration. It depicts the multi-layered innards of the modern pneumatic tire.

The details may seem whimsical, but they make a larger point, one surely obvious to most people outside the legal profession. Major industries in our modern economy are built on a vast, fast-growing infrastructure of systematized knowledge. A hundred million drivers aren’t cruising the American highway on the wheels of subjective impression. Whatever your business—engineering, immunology, lithography, software, failure analysis and no doubt beekeeping, too—the intellectual underpinnings of your livelihood are solidifying day by day. New science, newer technology, vast databases, statistical analyses and computer simulations have overtaken old wing-and-a-prayer ways of doing business. As Justice Breyer pointed out, no one else in the tire industry seems to draw fine distinctions the way Mr. Carlson does, or use his methods, or endorse them in any published article. In a brand new industry that might not tell you much. In one as huge and high-tech as tires, it tells you all you need to know—not about tires, but about the kind of “expertise” Mr. Carlson offered in court.

Systematic forms of inquiry are rapidly superseding the traditional tools of legal process, too—those centered on the lay witness and his accidental perceptions. The defense’s analysis of the failed tire in last week’s case uncovered a startlingly detailed history of neglect and wear. The only thing it didn’t uncover, really, was any defect in original manufacture. In other fields, forensic experts have become skilled at identifying and tracing genes, fibers, hairs, fabrics and dust. DNA testing provides all but ironclad pronouncements on key facts in rape and paternity cases. Yet another remarkable science ascertains dates of death by correlating the life cycles of maggots and other insects with the age of their host cadavers.

The Supreme Court’s 1993 ruling on expert testimony was the first in its entire history, but three more followed quickly. Lower courts now make pivotal rulings on expert testimony in almost every major trial. This is bad news for lawyers, the brokers of confusion and uncertainty. The more uncertain the key facts, the more lawyers get to litigate them. Hard science dispels uncertainty. Fog and smoke always advance the livelihood of at least one side’s lawyers, and usually of both. But the Supreme Court is now consistently calling for less smoke and more reliable experts. As Justice Antonin Scalia summed things up in his one-paragraph concurrence last week, federal judges must apply “reasonable means of excluding expertise that is fausse and science that is junky.”

Since 1993, the trial bar’s response has centered mainly on what might be called the science of personal destruction. Plaintiffs’ lawyers have taken to dumping harassing subpoenas, and in some instances lawsuits too, on mainstream scientists, the institutions that employ them, the journals that publish them, the professional peers who review their work and even newspaper reporters who write about it. The Mayo Clinic, Carnegie Mellon University, the editor of the New England Journal of Medicine and a reporter for the New York Times have all been among the targets.

“Diversity science” seems to be crystallizing as the trial bar’s second line of defense. A recent opinion piece in the Times put it this way: “Scientists continue to be mostly white and mostly male, [and] tend to represent only part of the population.”

There is a rare political opportunity here for people who believe in objective science—one that cuts across settled political alignments. Commitment to the norms of disciplined, systematic, scientific inquiry exists quite independent of views on taxes, abortion, the death penalty or school prayer. That commitment should unite corporate America with the more liberal scientific establishment, including major segments of academic communities. English professors and sociologists won’t sign up, but chemists, biologists, immunologists, engineers and physicians ought to. Professionals in these fields have strong reason to affirm the difference between hard science and the marshmallow kind.

Every Political Stripe

Professional associations have already taken to filing friend-of-the-court briefs in key cases. The Supreme Court cites them respectfully. In a major speech and a follow-up article published in the journal Science last year, Justice Breyer called for greater involvement of the mainstream scientific communities in legal process. Real scientists of every political stripe, and every corporation whose business depends on an infrastructure of reliable knowledge ought to help make that happen.

When the occasion warrants, serious beekeepers should be heard from too—not because they’ve “seen a lot of bees,” but because they study their field systematically, because their insights about Hymenoptera are based on published, tested, reliable methods, not subjective impression. Most of them, one might add, work with honeybees, not bumblebees—a detail, I suppose, but one that six appellate judges of the been-there-done-that school apparently overlooked. Say what you will about the flight characteristics of Bombus. When it comes to honey, Apis delivers most of the goods.