Statement of Task
A committee will be appointed to assess the validity of the scientific basis for the use of elemental composition determination to compare lead alloy-based items of evidence. The following three areas will be addressed:
Analytical method. Is the method analytically sound? What are the relative merits of the methods currently available? Is the selection of elements used as comparison parameters appropriate? Can additional useful information be gained by measurement of isotopic compositions?
Statistics for comparison. Are the statistical tests used to compare two samples appropriate? Can known variations in compositions introduced in manufacturing processes be used to model specimen groupings and provide improved comparison criteria?
Interpretation issues. What are the appropriate statements that can be made to assist the requester in interpreting the results of compositional bullet lead comparison, both for indistinguishable and distinguishable compositions? Can significance statements be modified to include effects of such factors as the analytical technique, manufacturing process, comparison criteria, specimen history, and legal requirements?
This committee will prepare an unclassified, written report at the end of the study.