Crime Scene Search and Physical Evidence Handbook

Book excerpt: This book provides detailed guidelines for the criminal investigator on the protection and reporting of the crime scene and the collection and preservation of various types of evidence. The proper recognition, collection and preservation of physical evidence is a critical link in the process of prosecuting criminal acts. Those persons even marginally involved in criminal investigation should have a basic knowledge of the principles presented in this handbook. This work details procedures and techniques for investigating crime scenes and explains the characteristics and value of physical evidence. Basic types of this evidence are defined, acceptable methods of collection and preservation are described, and the results which can be expected from crime laboratory analysis are explained. Detailed procedures are given for recording the crime scene and for processing such evidence as fingerprints, body fluids, trace evidence, firearms, tool marks, illegal drugs, chemical materials, paint, and glass. The preparation of casts, collection of residual prints, examination of questioned documents, and identification of the known dead are treated. The appendices contain recommendations for the collection, marking, preserving, and packing of physical evidence and a directory of criminalistics laboratories throughout the country.