ABSTRACT
The definition of trace as in the phrase trace evidence is more problematical. Historically, criminalistics and forensic sciences used trace evidence to describe any evidence small in size, particularly evidence that would be analyzed with microscopical techniques. In the not-too-distant past, even the analyses of small blood samples and bulk soil or dust samples were considered trace analyses. It is better to define trace analysis as the qualitative or quantitative analysis of the minor or ultraminor components of a sample, where “sample” means an entire submitted exhibit or a subsample of the exhibit. The section of a forensic laboratory where trace materials were submitted generally depended on the historical development of the laboratory. Large laboratories, for example, may have included separate sections for fiber, hair, mineralogy (soil), paint, serology, controlled substances, and firearms analyses. Small laboratories often grouped the sections differently, possibly as chemistry, biology, microscopy, drugs, and ballistics. The types of evidence examined by each area depended on the history of the laboratory. Hair examination cases were sometimes assigned to the biology group, while in other labs they may have been handled by the microscopy unit or chemistry section. Natural and synthetic fibers were assigned similarly to different units.
