The Supreme Court’s Daubert decision revolutionized the law governing the admissibility of expert witnesses. The decision imposes a duty on trial judges to decide whether expert testimony is sufficiently reliable to be admitted as evidence in court. While there remains widespread disagreement about whether Daubert is meant to open or close the door to expert testimony, the decision’s influence on American law is undeniable.
A majority of states have adopted some version of the Daubert analysis, although states often put their own spin on the role that judges should play when the assess expert witness testimony. One scholar has applauded the Daubert “revolution” for bringing “scientific enlightenment to the law.” Another has questioned whether judges are any better than juries at evaluating expert evidence. In short, opinions about Daubert are all over the map.
The Daubert Decision
The Daubert decision was the culmination of a lawsuit commenced by Joyce and Bill Daubert. Among other deformities, their newborn son was missing three fingers and a bone in his forearm. Doctors told her that she was probably exposed to something that caused her developing embryo to deform, but they could not identify the specific cause.
About ten years later, Joyce read a newspaper article about a little girl with symptoms that were similar to her son’s. The girl’s parents were suing Merrell Dow, alleging that the birth defects were caused by Bendecin. The company marketed the anti-nausea medication as a remedy for morning sickness.
In 1983, the parents of the little girl won a $750,000 verdict against Merrell Dow. Their lawyer called a reproductive epidemiologist and a pediatrician as expert witnesses. About two weeks later, Merrell Dow pulled Bendecin from the market.
The Dauberts brought their own lawsuit against Merrell Dow. They assembled a team of expert witnesses. By that time, pharmaceutical and insurance companies had launched a public relations campaign against “junk science.” The campaign disparaged juries as being too “sympathetic” to injury victims (as if human empathy is an evil trait) and contended that experts chosen by plaintiffs (but not drug companies) were “hired guns” who slanted their unscientific opinions to favor the parties who hired them.
Merrell Dow moved to dismiss the case without a trial, based on an epidemiological study that found no “reproducible or consistent association of birth defects with Bendectin exposure.” The Dauberts challenged that study. They relied on eight experts, including experts in reproductive epidemiology, developmental biology, toxicology, biostatistics, and pharmacology. The experts reanalyzed the epidemiological data and concluded that the study advanced by Merrell Dow did not rule out the possibility that Bendectin caused birth defects.
The trial judge sided with Merrell Dow. On appeal, the Ninth Circuit applied the Frye test for expert witness admissibility. The court concluded that the methods relied upon by the Dauberts’ experts were not a “generally accepted” means of proving causation and thus could not be admitted as evidence.
The Dauberts took their case to the Supreme Court. The Court rejected the Frye test. The question, the Court said, should be whether expert testimony is reliable, not whether it is based on a methodology that is generally accepted by other scientists. While acceptance is one factor that helps a judge assess reliability, making it the only factor prevents juries from hearing reliable evidence simply because it is new or novel.
The Supreme Court reversed the Ninth Circuit’s decision. It rejected the Frye standard and crafted an admissibility test that is now known as the Daubert standard. The New York Times reported that the Court raised the bar for admitting expert testimony. The Washington Post reported that the Court lowered the bar. That controversy has continued to this day.
The Aftermath of Daubert
The Ninth Circuit applied the new standard and again rejected the Dauberts’ experts. This time, the court concluded that epidemiological evidence did not prove that Bendectin exposure would double a child’s risk of being born with birth defects. If the risk is not doubled, the court decided, it was impossible to say that birth defects were probably caused by Bendectin.
Putting aside the wisdom of the decision, the Ninth Circuit’s reasoning has been widely adopted. Judges have used it to reject expert testimony in a variety of contexts that involve potentially dangerous exposures, from chemical products and pollutants to radiation from power lines and cellphones.
The Ninth Circuit judge who wrote the decision rejecting the Dauberts’ claim later became an advocate for applying the Daubert standard in a way that benefits not just corporations accused of wrongdoing, but defendants who are accused of committing crimes. The judge noted that government crime lab employees too often view their jobs as helping prosecutors, not as seeking the truth. They rely on junk science to prove guilt without regard to its unreliability.
The legal system has been slow to reject the testimony of crime lab analysts who were allowed for decades to base opinions on anecdotal evidence rather than rigorous methodologies. While change does not come easily, courts are beginning to recognize that dubious testimony about bite marks, hair comparisons, blood spatter, and other branches of forensic science cannot be considered as proof of guilt.
What Happened to the Dauberts?
Where did the Daubert decision leave the Dauberts? Joyce feels that justice was not done because she never had her day before a jury. In the absence of any better explanation for her son’s birth defect, she still blames Merrell Dow. She might be right, but the Ninth Circuit’s questionable belief that doubling a relative risk is essential to proof of causation has become widely accepted by federal judges.
On the other hand, Joyce’s son — who is now 46 and working in the field of information technology — appreciates that a case bearing his name is being used to reduce the risk of innocent defendants being convicted on the strength of junk science. While disagreement about the application of Daubert in civil cases continues to spark controversy, there is a growing recognition of its importance as a shield against overzealous prosecutors who disguise biased opinions as “expertise” in their effort to convict accused defendants.