Using Scientists As Courtroom Witnesses: System Needs Improvement

Scientific issues now permeate a multitude of legal matters--the presentation of criminal evidence, cases involving intellectual property, environmental disputes, and so on. And, by all accounts, the courts are handling this surge of scientific adjudication poorly: Mishandling of scientific matters in court has been blamed for outrageous tort awards, improper criminal convictions, and even the erosion of the United States' competitiveness. In my view, the legal system's inability to properly manage scientific disputes stems in part from the problem of competition within the legal field--and the presence of scientists who, in this adversarial environment, trade the values of science for those of law. Lawyers, who dwell--and properly so--in an adversarial realm, are governed by written rules of professional conduct that require them to show loyalty to their clients, protect their clients' interests, and act as zealous advocates on their clients' behalf. These rules are suited to their profession. Scientists, on the other hand, have no written rules of professional conduct. But the scientific community appears to have developed strong unwritten professional rules--based on norms of intellectual objectivity--that are different from those governing lawyers. The differing rules properly reflect the differing goals of each discipline. The goal of law is to resolve disputes among citizens peacefully, whereas science's overriding goal is to construct a coherent view of the physical universe. Naturally, the rules of the scientific community exist to further the scientific endeavor: Scientists are expected to dedicate their discoveries to the use of the scientific community, to recognize meritorious ideas without respect to the status of the discoverer, to present their findings in an unbiased manner, and to subject new ideas or theories to rigorous testing before accepting them into the canon of scientific knowledge. In a court, however, the norms of science may quickly be superseded by those of law. A newcomer to the legal arena--such as a scientist hired as an expert--may be seduced, knowingly or not, into the "gaming" aspects of litigation, participating as an advocate and effectively adopting the advocacy style of law, rather than holding to the objective stance of science. Thus, the expert may begin to color his or her scientific testimony to obtain a "victory" for his "team," and may begin to make statements that he or she would not be comfortable making in a scientific journal or at a scientific meeting. In other cases, scientists who become associated with legal disputes may from the start be conceptually biased toward the objectives of one party. Legal disputes often have ramifications for the quality of life in our society, and it is the courts that often determine what products are allowed on the market, what substances are released into the environment, or what evidence is used to prove criminal conduct. Scientists, like everyone may have strong opinions on how these questions should be resolved, and so may be tempted to color their testimony to encourage their preferred outcome. Whatever the expert witness' motives, courts are poorly equipped to deal with the blatant advocacy, the subtle bias, or the preposterous notions that might be present in--or drive--a scientist's expert testimony. Lawyers, judges, and jurors are seldom scientifically literate, and the legal system often fails to recognize that the evidence presented in a case strays beyond the acceptable bounds of scientific opinion. Because legal decisions based upon such faulty scientific evidence are likely to be as deficient as the testimony itself, the result is legal precedent that not only is bad for the parties, but also is often bad for society generally. Of course, not all scientific experts abandon the norms of their profession to become advocates when they enter the courtroom. Even when adversarialism seems the order of the day, scientific responsibility may reassert itself. Such was the case, for example, in People v. Castro, a 1989 New York criminal proceeding in which forensic DNA was at issue. In Castro, the defendant was accused of murdering a woman and her daughter; DNA analysis was employed to try to match blood stains on the defendant's watch with the blood of the victim. Expert witnesses were recruited by both the prosecution and the defense, and adversary science quickly set in. As one expert later put it: "The court system is adversarial, and expert witnesses are encouraged to go further in their statements than they might otherwise be prepared to go." In the Castro case, however, scientific experts on both sides soon became uneasy about the quality of the DNA evidence. In a most unusual move, the experts from both the prosecution and the defense met together, without lawyers present, and reached agreement concerning the scientific soundness of the DNA data. They presented a consensus report of their findings to the court and testified concerning its contents. As the same expert put it: "We all did much better when we sat down without the lawyers and had a reasoned scientific discussion." This incident, however, remains the rare exception rather than the rule. To foster more instances of scientific responsibility in court, several mechanisms have been pro- posed to make the court system more hospitable to the norms of science. Perhaps the most enduring of these proposals has been that suggesting a process whereby factual questions of science would be considered separately from court proceedings and in which distinguished scientists would serve as the judges. In this proposed forum, it is hoped, problems stemming from a scientifically nave judiciary would be reduced, if not eliminated. Implementation of this sort of process, however, has never materialized. Indeed, the idea has been strongly criticized. Perhaps the most cogent of these criticisms is simply that science has already developed a method of validating knowledge and resolving controversies--the "organized skepticism" of careful experiments and of peer review. And application of "organized skepticism" to a legal proceeding, the argument goes, tends to conform more to the norms of legal proceedings than it does to those of objective scientific assessment. An alternative proposal with more promise would involve convening "consensus conferences" designed to define the "state of the science" in areas involving scientific controversy. Under this proposal, a consensus conference would be convened on matters of scientific controversy in order to produce unbiased expert reports that would guide the decisions of courts. The conference report would seek to suggest the acceptable range of scientific opinion relevant to a particular case, including areas of uncertainty or disagreement. Because the report would be fashioned outside the courtroom, in an atmosphere of consensus- building and scientific discussion, it presumably would be largely free of the biases introduced by the traditional adversary legal system as manifested in the courtroom. The consensus conference model, however, has also received its share of criticism. Most important, the consensus process is unwieldy, requiring substantial resources--including sufficiently sophisticated personnel--to assemble and guide the panel of experts. It is difficult to determine in advance what scientific matters are likely to appear in court, and the consensus process, once initiated, may take considerable time. Meanwhile, the courts are required to move ahead with their duties, and many poor decisions may be reached before a consensus report ever appears. Moreover, science moves on, altering its views in the light of new evidence. Thus, the consensus report can only provide a snapshot of scientific opinion at a particular moment in time; within a few years, a new conference is likely to be required in order to express the changes of opinion in the scientific community on a particular matter. A less-cumbersome procedure for improving the level of science expertise in courts has been suggested: that the court, rather than the parties to the dispute, recruit the science expert. Presumably, an expert who is not being paid by one party or the other will be less inclined to identify with that party's position. The rules governing federal courts already empower trial judges to exercise this option. Under the federal rules, a judge may select a court-appointed expert and require the parties to pay for the expert's time. However, some concerns have been expressed over this option, as well. It has been suggested, for example, that juries might abdicate their fact-finding role in favor of the opinion of the court's scientific expert simply because the expert is associated with the hallowed institution of the courtroom. Perhaps a more serious problem with use of court-appointed experts centers on the question of how the experts are to be selected. Many problems of the current system arise from the inability of a scientifically illiterate judiciary to screen out experts with opinions that are not accepted by the scientific community. There is no guarantee that a court appointing its own expert would not inadvertently appoint experts with such opinions. Therefore, in order for this scheme to succeed, courts must somehow be supplied with reliable information on competent experts. I believe that the best source for such validating information would be such respected scientific societies as the American Chemical Society or the American Association for the Advancement of Science (AAAS). By maintaining a roster of competent experts, these societies could play a major role in helping the courts deal with scientific issues. This suggested role for professional societies as recommenders of scientists worthy of being court-appointed experts recently has been endorsed by the National Council of Lawyers and Scientists (NCLS), a joint committee of AAAS and the American Bar Association. In a recent report to the Carnegie Commission on Science, Technology, and Government, NCLS recommended a prominent role for professional societies in providing scientific expertise to the courts. Another intriguing suggestion has been put forward by two commentators, Nancy Ellen Abrams and R. Stephen Berry of the NCLS task force, as part of the council's Carnegie Report. This proposal attempts to assemble the best aspects of previous proposals by drawing on the power of federal judges to appoint "special masters" to oversee particularly complex portions of a case. Under this proposal, a scientifically trained special master, or "scientific referee," would be appointed to assist the court in collecting and evaluating scientific evidence. The referee would then preside over the preparation of a report by two experts of differing viewpoints that defines the acceptable range of scientific opinion by stating the areas on which the experts agree, the areas on which they disagree, and why they disagree. In a sense, the report would be equivalent to a "mini-consensus conference" report, effectively institutionalizing the sort of agreement process that spontaneously took place among the experts in the Castro case. All innovative proposals concerning a better way for science and the law to work harmoniously and productively deserve consideration. Meanwhile, the unwritten rules of acceptable scientific behavior remain in place, but they are too frequently ineffectual in serving either science or justice. Both the legal and scientific communities must increase their attention to this deficiency, for while there must always be room for adversarial lawyers in the courtroom, there should be no room for adversarial science. Dan L. Burk, a molecular biologist and attorney, currently is a Teaching Fellow at Stanford University.

Using Scientists As Courtroom Witnesses: System Needs Improvement

Interested in reading more?

Become a Member of