1.23 - Legal and Forensic Sampling

Abstract

This chapter covers the diverse topics within sampling and sample preparation for forensic chemical analysis. Sampling and sample preparation are the first and sometimes neglected steps in obtaining meaningful data from analytical measurements. The chapter covers the role of statistics and the importance of developing a sound sampling strategy and the role of sampling and sample preparation for matrices that are normally examined in forensic laboratories, such as residues of ignitable liquids present in debris collected from suspect fires, residues of explosives (both pre-blast and post-blast), residue from gunshot collected from persons suspected of firing a weapon, controlled substances in solid form and from biological specimens, the characterization of materials such as glass, paint, fibers, and other “trace” evidence, human odor compounds and human decomposition compounds as well as a variety of matrices and analytes related to environmental forensic samples. The chapter also covers the use of field sampling and sample preparation to facilitate analytical measurements closer to where the evidence sample was found.