Saturday, June 1, 2013
Several people have asked me to explain the Daubert rule and compare it to the Frye rule. Today is a good opportunity to do that since we are experiencing a bit of calm before the storm.
Judge Nelson scheduled a Frye hearing for June 6 and 7 to determine whether to permit the State to present expert testimony identifying voices in the background of a 911 call. The purpose of a Frye hearing is to determine whether to admit evidence derived from a new or novel scientific theory or methodology. In Frye v. United States, 293 F. 1013 (D.C. Cir. 1923), the Court held that such evidence should be excluded unless the new or novel scientific theory or methodology is generally accepted in the relevant scientific community.
I previously wrote about the Frye rule here. Basically, it is a counting heads test that does not require the trial judge to understand the new or novel scientific theory or methodology.
The disadvantage of the Frye rule is that it may result in the exclusion of results obtained with theories and methodologies that are capable of producing accurate and reliable results, but are too new to have passed the test of peer review and become generally accepted in the relevant scientific community.
This hole in the Frye rule eventually led to the SCOTUS adopting a new rule in Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993). Significant changes in long existing legal rules generally require compelling facts, particularly if the rule change is going to cost corporate America big money. Daubert was such a case.
Writing for the majority, Justice Blackmun described that set of facts at pp. 582-583:
Petitioners Jason Daubert and Eric Schuller are minor children born with serious birth defects. They and their parents sued respondent in California state court, alleging that the birth defects had been caused by the mothers’ ingestion of Bendectin, a prescription antinausea drug marketed by respondent. Respondent removed the suits to federal court on diversity grounds.
After extensive discovery, respondent moved for summary judgment, contending that Bendectin does not cause birth defects in humans and that petitioners would be unable to come forward with any admissible evidence that it does. In support of its motion, respondent submitted an affidavit of Steven H. Lamm, physician and epidemiologist, who is a well-credentialed expert on the risks from exposure to various chemical substances. Doctor Lamm stated that he had reviewed all the literature on Bendectin and human birth defects—more than 30 published studies involving over 130,000 patients. No study had found Bendectin to be a human teratogen (i. e., a substance capable of causing malformations in fetuses). On the basis of this review, Doctor Lamm concluded that maternal use of Bendectin during the first trimester of pregnancy has not been shown to be a risk factor for human birth defects.
Petitioners did not (and do not) contest this characterization of the published record regarding Bendectin. Instead, they responded to respondent’s motion with the testimony of eight experts of their own, each of whom also possessed impressive credentials. These experts had concluded that Bendectin can cause birth defects. Their conclusions were based upon “in vitro” (test tube) and “in vivo” (live) animal studies that found a link between Bendectin and malformations; pharmacological studies of the chemical structure of Bendectin that purported to show similarities between the structure of the drug and that of other substances known to cause birth defects; and the “reanalysis” of previously published epidemiological (human statistical) studies.
The Court held that Rule 702 of the Federal Rules of Evidence replaced the Frye Rule. Rule 702 states:
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, if
(1) the testimony is based on upon sufficient facts or data,
(2) the testimony is the product of reliable priniciples and methods, and
(3) the witness has applied the principles and methods reliably to the facts of the case.
[Note that the language beginning with “or otherwise, if” was added to the rule in 2000 after the SCOTUS decided Daubert]
Application of Rule 702 must involve a consideration of the following factors discussed at pp. 592-595:
Faced with a proffer of expert scientific testimony, then, the trial judge must determine at the outset, pursuant to Rule 104(a), whether the expert is proposing to testify to (1) scientific knowledge that (2) will assist the trier of fact to understand or determine a fact in issue. This entails a preliminary assessment of whether the reasoning or methodology underlying the testimony is scientifically valid and of whether that reasoning or methodology properly can be applied to the facts in issue. We are confident that federal judges possess the capacity to undertake this review. Many factors will bear on the inquiry, and we do not presume to set out a definitive checklist or test. But some general observations are appropriate.
[Note that the previous paragraph changes the trial court’s job from counting heads to functioning as a gatekeeper]
Ordinarily, a key question to be answered in determining whether a theory or technique is scientific knowledge that will assist the trier of fact will be whether it can be (and has been) tested. “Scientific methodology today is based on generating hypotheses and testing them to see if they can be falsified; indeed, this methodology is what distinguishes science from other fields of human inquiry.” Green 645. See also C. Hempel, Philosophy of Natural Science 49 (1966) (“[T]he statements constituting a scientific explanation must be capable of empirical test”); K. Popper, Conjectures and Refutations: The Growth of Scientific Knowledge 37 (5th ed. 1989) (“[T]he criterion of the scientific status of a theory is its falsifiability, or refutability, or testability”) (emphasis deleted).
Another pertinent consideration is whether the theory or technique has been subjected to peer review and publication. Publication (which is but one element of peer review) is not a sine qua non of admissibility; it does not necessarily correlate with reliability, see S. Jasanoff, The Fifth Branch: Science Advisors as Policymakers 61-76 (1990), and in some instances well-grounded but innovative theories will not have been published, see Horrobin, The Philosophical Basis of Peer Review and the Suppression of Innovation, 263 JAMA 1438 (1990). Some propositions, moreover, are too particular, too new, or of too limited interest to be published. But submission to the scrutiny of the scientific community is a component of “good science,” in part because it increases the likelihood that substantive flaws in methodology will be detected. See J. Ziman, Reliable Knowledge: An Exploration of the Grounds for Belief in Science 130-133 (1978); Relman & Angell, How Good Is Peer Review?, 321 New Eng. J. Med. 827 (1989). The fact of publication (or lack thereof) in a peer reviewed journal thus will be a relevant, though not dispositive, consideration in assessing the scientific validity of a particular technique or methodology on which an opinion is premised.
Additionally, in the case of a particular scientific technique, the court ordinarily should consider the known or potential rate of error, see, e. g., United States v. Smith, 869 F. 2d 348, 353-354 (CA7 1989) (surveying studies of the error rate of spectrographic voice identification technique), and the existence and maintenance of standards controlling the technique’s operation, see United States v. Williams, 583 F. 2d 1194, 1198 (CA2 1978) (noting professional organization’s standard governing spectrographic analysis), cert. denied, 439 U. S. 1117 (1979).
Finally, “general acceptance” can yet have a bearing on the inquiry. A “reliability assessment does not require, although it does permit, explicit identification of a relevant scientific community and an express determination of a particular degree of acceptance within that community.” United States v. Downing, 753 F. 2d, at 1238. See also 3 Weinstein & Berger ¶ 702, pp. 702-41 to 702-42. Widespread acceptance can be an important factor in ruling particular evidence admissible, and “a known technique which has been able to attract only minimal support within the community,” Downing, 753 F. 2d, at 1238, may properly be viewed with skepticism.
The inquiry envisioned by Rule 702 is, we emphasize, a flexible one. Its overarching subject is the scientific validity—and thus the evidentiary relevance and reliability—of the principles that underlie a proposed submission. The focus, of course, must be solely on principles and methodology, not on the conclusions that they generate.
And there you have it.