Ipse dixit

Abstract: I. Introduction From the viewpoint of conventional science, the forensic identification sciences are contenders for being the shoddiest science offered to the courts.1 After being in business for nearly a century, they still have developed little that would be recognized as a scientific foundation and, consequently, have little basic science to apply to their operational activities. For much of the twentieth century, the courts readily admitted these fields, apparently because they were flying the banner of science and not because they presented sound data supporting their claims. The decision in Daubert v Merrell Dow Pharmaceuticals, Inc.2 concluded that the duty of judicial gatekeeping of expert testimony could be met only if judges were persuaded of the soundness of an expert's underlying claims.3 No me was more surprised than the judges when they realized that subjecting the forensic identification sciences to Daubert scrutiny led to the conclusion that they should be excluded.4 Consequently, after Daubert courts began to look for ways to avoid its application to the forensic identification sciences. Moreover, some forensic identification scientists looked for ways to evade Daubert scrutiny. The solution to this problem for those judges and for pseudo-scientists was to re-classify those fields as non-science.5 But Kumho Tire Co. v. Carmichael6 patched that hole, so to say, at least by its apparent terms.7 That is to say, hauling down the science flag and hosting the non-science flag does not exempt expert evidence from Daubert scrutiny.8 Together, Daubert and Kumho Tire do a remarkably clear job of commanding judges to property scrutinize fields, presumably including the forensic identification sciences, before admitting opinions from those fields' practitioners. But one can never underestimate the ingenuity of judges in finding ways to evade rules that tell them to do something that would lead to a result contrary to the one suggested by their intuitions. The post-Daubert, pre-Kumho Tire period was telling: Obeying the letter and spirit of Daubert would lead to significant exclusion of a type of evidence that the courts welcomed for most of the twentieth century. On the other hand, a ruling to admit these fields would be both a rejection of conventional science as the criterion for admission of empirical claims and a ruling in the teeth of repeated unanimous Supreme Court opinions declaring the conventional scientific method to be the touchstone for evaluating empirical claims of all kinds. The question with which this Article is concerned is: What are the prospects that Kumho Tire will compel courts to follow the commands of Daubert and to exclude expert opinions "connected to existing data only by the ipse dixit of the expert"?9 II. Defining the Fields Let us be clear about the fields that we are discussing. There are two kinds of forensic science: On the one hand, there are normal applications of basic science. On the other hand, there is individualization science, or identification science. My focus will be on the latter, though it will not be my exclusive focus. Normal forensic science does things like determining what substance something is (e.g. …

Abstract: In reply: We thank Dr Murray and his colleagues and Dr Ferguson for their interest in our article. Debate in scientific literature is important for the field to advance and for all sides to be heard. One of the senior authors of our article, a law professor (T.D.), thinks it is important to remember that the First Amendment to the US Constitution, which was at issue in the case of Brown (formerly Schwarzenegger) v Entertainment Merchants Association, allows the medical profession and the population at large to engage in vigorous substantive debate.1 We think that the letter from Ferguson speaks for itself. In this reply, we focus on the letter from Murray et al entitled A Plea for Concern because they express more disagreement and concern with our article and its premise. Unfortunately, their letter enforces the points we made in our article that some in the scientific community are acting in an overly emotional, biased, academically dishonest, and ipse dixit (legal term for something asserted but not proved) “I am the expert” manner that hampers medicine's credibility and objectivity in our courts.

Abstract: Compositional comparisons of bullet lead, where questioned samples obtained from a crime scene are compared with known-source bullets seized from a suspect, a forensic practice known as comparative bullet lead analysis (CBLA), has been admitted into evidence by courts for over 30 years as evidence of criminal guilt if the compositions were considered "analytically indistinguishable." The first part of this paper reviews the state of the technological and scientific record, with special emphasis on the permissibility of the expert witness' ultimate inference as to whether the crime scene bullet originated from the same manufacturer, molten source, batch, or box, as the bullets attributable to the suspect.The second part analyzes the state of the scientific record in light of the governing legal standards, namely, the Frye general acceptance test and the competing validation standard enunciated in Daubert and its progeny the Supreme Court's 1999 decision in Kumho Tire Co., Ltd. v. Carmichael.In the final analysis, we conclude that courts and practitioners were seduced for over three decades by the sophistication of the analytical instrumentation and precision of the generated data, and proffered evidence that was meaningless and had no probative value for judicial proceedings.