Vol. 9, No. 5, Pg. 32. Organization and Admissibility of Complex Scientific Evidence: Helping your Jury Understand.

• Author: By Timothy W. Bouch and D. Jay Davis Jr.

South Carolina Lawyer

1998.

Vol. 9, No. 5, Pg. 32.

Organization and Admissibility of Complex Scientific Evidence: Helping your Jury Understand

32ORGANIZATION AND ADMISSIBILITY OF COMPLEX SCIENTIFIC EVIDENCE: HELPING YOUR JURY UNDERSTANDBy Timothy W. Bouch and D. Jay Davis Jr.Scientific evidence, expert witnesses, technological principles, volumes of literature--all are commonplace in today's complex lawsuits. Lay juries are required to digest the facts, examine the evidence, understand it and reach a fair result--or at least your result. Unless you digest it, examine it and understand it, your clients, your reputation and your future business will suffer. Complex litigation requires organization, knowledge and communication.

Daubert--The Continuing Benchmark

With many complex trials come opportunities for use of scientific evidence. Much of this evidence is highly relevant. Some is very helpful to the trier of fact. Most of it is not.

Ever since the Supreme Court's decision in Daubert v. Merrell-Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), the courts have wrestled with the proper application of a scientific standard for admissibility under the Federal Rules of Evidence. Article Seven of the Federal Rules deals with opinions and expert testimony. Rule 702 provides: If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education may testify thereto in the form of an opinion or otherwise.

The Supreme Court held in Daubert that trial judges were to become "gatekeepers," whose task would be to ensure that an expert's testimony was both scientifically reliable and relevant. 509 U.S. at 589.

In Daubert, the Court set out a two-prong test for the admissibility of scientific evidence under the Federal Rules of Evidence. First, a court is to inquire into the: (1) scientific reliability of the evidence; and (2) the helpfulness of the evidence to the jury.

34Reliability. The Court first defined evidentiary reliability by interpreting the words "scientific knowledge" under Rule 702 to refer to knowledge which has an adequate basis in the methods of science and is subject to appropriate validation. Id. at 590. The Court found that the trial judge must assess "whether the reasoning or methodology underlying the testimony is scientifically valid." Id. at 592-93. The focus must be "solely on principles and methodology, not on the conclusions that they generate." Id. at 595.

Under Rule 702, the evidence must "assist the trier of fact to understand the evidence or to determine a fact in issue." The Court found that the evidence must have a "valid scientific connection to the pertinent inquiry as a precondition to admissibility." Id. at 592. In other words, there must be a sufficient nexus between the expert testimony and the facts of the particular case. This nexus must assist in resolving the dispute. Id.

Additional Factors. The Supreme Court provided a non-exdusive list of factors that may be considered by the trial judge. 509 U.S. at 593-94. These factors indude:

(1) Whether the theory or technique can be or has been tested (i.e., falsifiability); (2) peer review and publication of the theory or technique; (3) the known and potential rate of error, and the existence and maintenance of standards controlling the technique's operation; and (4) general acceptance of the methodology or technique in the scientific community.

The Daubert Court recognized a distinction between scientific reliability and scientific validity. Scientific validity describes how well the scientific method reaches its conclusion. Scientific reliability is the ability of the scientific method to produce consistent results when replicated. "For example, a new test for blood alcohol level may be invalid in that it grossly underestimates the amount of alcohol in one's bloodstream, and yet may be reliable in that it underestimates the blood alcohol level in one's bloodstream by the same amount every time." See "Confronting the New Challenges of Scientific Evidence." 108 Harv. L. Rev. 1480, 1534 (1995).

In Daubert, the Supreme Court directed trial judges to rely exclusively on scientific validity in their evaluation of the legal reliability prong. 509 U.S. at 590 n.9. Notwithstanding this mandate, several have found in practice that evidentiary reliability also requires some level of scientific reliability as well. See 108 Harv. L. Rev. at 1534. The test mandated by Daubert requires courts to assume a "scientific" role. This non-traditional role has proved difficult for some courts.

Legal Relevancy. The second prong of the Daubert test requires that there be a nexus between otherwise valid scientific evidence and the case at hand. It requires that the court assess the validity of the application of the science to the case.

A pre-Daubert effective application of this test occurred in In re Paoli Railroad Yard PCB Litigation, 916 F.2d 829 (3d Cir. 1990), where the court admitted evidence that polychlorinated byphenyls (PCBs) caused liver cancer even though the plaintiffs did not have liver cancer. The court found that increased risk of liver cancer was probative of increased risk of other forms of cancer and that the method was scientifically valid and legally reliable because there was some probative value in a link to other forms of cancer. Many courts have excluded other theories of extrapolation where the theory of extrapolation itself was invalid. See, e.g., Dodd-Anderson v. Stevens, 1994 Westlaw 26922 (D.Kan. 1994).

Scientific testimony can be divided into four stages, which form the basis for most, if not all, expert opinion:

(1) expert's choice of methodology; (2) application of the methodology to the facts of the case; (3) execution of the chosen methodology in the particular case; and (4) the expert's conclusions based on the execution of the methodology.

See Kesan, "An Autopsy of Scientific Evidence in a Post-Daubert World," 84 Georgetown L.J. 1985, 2018-23 (1996). These four stages are the most frequently attacked portions of the testimony. The most commonly rejected evidence in the post-Daubert world occurs where an expert's choice of methodology cannot be readily discerfga by the court. Kesan, supra, at 2023.

In Richardson v. United States, 835 F. Supp. 1236, 1239-40 (E.D. Wash. 1993), the court examined the methodology employed and the factors relied on by both experts. It determined that the experts' methodologies were faulty because they lacked scientific foundation.

In Duffee v. Murray Ohio Manufacturing Co., 879 F. Supp. 1078 (D. Kan. 1995), an 11-year-old boy was injured when his bicycle collided with a car. The parents brought suit, claiming design defects in the braking system of the bicycle. Plaintiffs hired a

35mechanical engineer to examine the brake design. His methodology was based on such "persuasive" factors as his personal experience riding bicycles, a conversation with a single bicycle retail dealer and his own backyard testing of bicycle stopping distances on the hill at the accident site. Id. at 1086.

The court found numerous flaws in the methodology used by the...