Finding: Detailed patterns of distribution of ammunition are unknown, and as a result an expert should not testify as to the probability that a crime scene bullet came from the defendant.145 Geographic distribution data on bullets and ammunition are needed before such testimony can be given.

Recommendation: The conclusions in laboratory reports should be expanded to include the limitations of compositional analysis of bullet lead evidence.146 In particular, a further explanatory comment should accompany the laboratory conclusions to portray the limitations of the evidence. Moreover, a section of the laboratory report translating the technical conclusions into language that a jury could understand would greatly facilitate the proper use of this evidence in the criminal justice system.147 Finally, measurement data (means and standard deviations) for all of the crime scene bullets and those deemed to match should be included.

145  

See State v. Noel, 697 A.2d 157, 162 (N.J. Super. App. Div. 1997) (“Nor was any testimony offered as to marketing, that is, whether, as seems likely, bullets from the same billets would be shipped together by the manufacturer and hence that there would be a concentration of such bullets in a specific geographical region.”), rev’d on other grounds, State v. Noel, 723 A.2d 602 (N.J. 1999).

The defense attorney in United States v. Jenkins, CR. No. 3:96-358, U.S. Dist. Ct., South Carolina, Columbia Div., Sept. 30, 1997, argued: “No company has still today provided us with any information from which we know whether all of this ammunition ended up in Columbia, South Carolina, or whether it was randomly distributed all over the country.” Transcript at 157.

Testimony of Charles Peters, Commonwealth v. Wilcox, Kentucky, Feb. 28, 2002, Transcript, (Daubert hearing & trial testimony). Question: “And do we have any information as to the geographic distribution of these bullets?” Peters: … “Uh, I, I don’t know the information. I, uh, obviously, uh, uh, to answer that question would bring somebody in from PMC.”

146  

Professor Anna Harrison, Mount Holyoke College, during a symposium on discovery, remarked: “Then the information you are receiving is not scientific information. For a report from a crime laboratory to be deemed competent, I think most scientists would require it to contain a minimum of three elements: (a) a description of the analytical techniques used in the test requested by the government or other party, (b) the quantitative or qualitative results with any appropriate qualifications concerning the degree of certainty surrounding them, and (c) an explanation of any necessary presumptions or inferences that were needed to reach the conclusions.” Symposium on Science and The Rules of Legal Procedure, 101 F.R.D. 599, 632 (1984) (emphasis added).

147  

This recommendation will reduce the potentially misleading character of the evidence. See discussion of prosecution summary in State v. Noel, supra.



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