permitted concentration range for each element, and the discrimination of the analytical technique for each. Considering the thousands of “batches” of lead produced over a number of years, there is a reasonably high probability that some will repeat. However, the probability that any given composition would repeat within the next several years could be expected to be quite low. Furthermore, the likelihood that such a coincidental match would occur from such a source and appear in a given case would be smaller still.
In summary, a CIVL would be large in comparison with the amount of lead in the ammunition in the possession of a typical single purchaser. Thus, multiple people would be expected to have ammunition with the same lead composition. It is not known how many of these would be in the same geographic area. As time passes and some of the ammunition is used, the likelihood of a false association because of the distribution of ammunition with lead from the same CIVL would decrease.
If several evidence bullets in a case have similar but distinguishable compositions, and each of these compositions has a counterpart in a known source, such as a box of ammunition, the association would be stronger.