"The science done in a crime laboratory serves a specific function: to analyze the evidence on which the criminal justice system relies. The analytic practices they use-in terms of biology or chemistry-are similar to those one would see in an academic, industrial, or hospital lab. Yet the purposes toward which forensic scientists use their expertise are different. Unlike other scientists, their goal is to analyze possible material links between a suspect and a crime, and they perform their work only for the criminal justice system. This book examines the particular culture of the crime lab and reveals how crucial it is to understand the social worlds of experts working fields where knowledge is evolving and contested. The author builds on eighteen months of fieldwork conducted within a crime lab of a major metropolitan area in the western United States. The book focuses on four forensic science units in the lab: forensic biology, chemistry, comparative evidence, and toxicology. Bechky examines a typical day in each of the various disciplines as the expert criminalists receive new evidence, process ongoing cases, write up reports, and worry about testifying. Although the particulars of their analyses are different, criminalists across disciplines must navigate between the worlds of science, criminal justice, and the general public, which requires not only scientific acumen, but also the ability to anticipate and translate for these audiences. Blood, Powder, and Residue is a rich ethnography of forensic science, and a powerful account of expert work in practice"-- Provided by publisher.