Since the proliferation of sophisticated products litigation in the 1960s, manufacturers have often been plagued by the effectiveness of adverse expert witnesses.
Expert testimony (and opinions concerning the product) may be permitted in the broad discretion of the court to aid the jurors as to those issues which may be outside the scope of their common knowledge or understanding. Complicated biomechanical, toxicology, medical, and other technical issues often require explanations by someone purportedly trained in the particular field or discipline.
The problem is frequently exacerbated by the trial judge, whose function it is to approve or disapprove of the witness as an expert. Generally, a review of the proposed expert's background, education, experience, and training guides the judge as to the admissibility of opinion the proposed witness offers.
Indeed, technical experts for the plaintiff have often demonstrated a remarkably shallow background upon which to support his or her expertise.
Case that gives judges more leeway. A United States Supreme Court case, Daubert v. Merrell Dow Pharmaceuticals Inc., 113 S. Ct. (1993), established the boundaries of acceptable expert testimony. The plaintiffs contended that their serious birth defects were caused by their mother's prenatal ingestion of Bendectin, an anti-nausea drug often prescribed in the past to expectant mothers. The available medical literature concluded that maternal use during the first trimester of pregnacy is not a risk factor for human birth defects.
The plaintiffs didn't contest the published record. Instead the plaintiffs' eight experts did animal studies, studied the structure of Bendectin compared with other drugs known to cause birth defects, reanalyzed published human statistical studies, and came to different conclusions.
The Supreme Court (SC) decided that it is the trial judge's duty to ensure the relevance and reliability of the expert testimony.
Testing the evidence. A judge must consider four flexible factors, which the SC set forth, when evaluating expert testimony. 1.) Can the theory be--and has it been--tested? Are the statements made capable of empirical testing? 2.) Has the basis of the testimony been subject to peer review or publication? (The SC left the door open so that very new theories or those too limited to be published could also be considered.) 3.) What is the known or potential rate of error for the scientific evidence offered? 4.) Has the subject matter of the testimony gained "general acceptance" in the scientific community?
The Supreme Court also cautioned that the trial courts had other tools at their disposal to limit expert testimony. They can limit hearsay testimony, appoint their own "independent" expert, and exclude evidence altogether if they believe that the evidence's prejudice would outweigh its probative value.
It remains for the future to bear out the impact of the Daubert case. The case will be binding on federal cases, but not those at the state level, since it deals with the Federal Rules of Evidence. There are a number of states, however, whose evidentiary rules track the federal rules in whole or in part. In those states, we can expect that the rationale of Daubert will be applied.
Q What are the immediate ramifications coming out of the Daubert case?
A Many members of the defense bar, with whom I concur, have hailed the decision as a victory in that it rejects a "let it all in" philosophy and requires the judge to take an active, as opposed to passive, role in the determination of admissibility. (Clifton T. Hutchinson, Daubert Confirms Judge's Gatekeeper Role, BNA Product Safety & Liability Reporter, Vol. 21, #30, Part II.) It has been suggested that defendants might invoke certain pretrial devices to dispose of expert testimony more often since Daubert was decided, for example, by filing motions in outside the presence of the jury, motions for summary judgment and even formal hearings.
On the other hand, another view holds that the Daubert decision will make little difference in the long run. Daubert is flexible enough so that a liberally inclined judge can find support for admitting controversial evidence, while a more conservative judge can likewise find support to exclude the evidence. (Reavley, Thomas M., Daubert May Be Read To Allow Broad Judicial Control in Evaluating Reliability, BNA Product Safety & Liability Reporter, Vol. 21,
Q What is the most effective method to control the "scientific" opinion evidence offered through basically unqualified experts?
A The defendant attorney should meticulously follow the four prong test, while quizzing the expert at his or her deposition to pin them down as to the source or basis for each and every opinion offered.