Scientific police investigation

the long version

This book is a guide for the working patrolman on possibilities for scientific criminal investigation, with measures for preserving and collecting evidence at the crime scene. 'Oh, how simple it would have been had I been here before they came like a herd of buffaloes and wallowed all over it'. These are the words of fictional detective Sherlock Holmes expressing his concern over the destruction of some valuable crime scene evidence. This book is not a textbook for specialists and experts in criminalistics nor does it deal with general considerations of criminal investigation. It addresses itself instead to the working patrolman who is summoned to the scene of a crime as the initial representative of the law. Its primary purpose is to make him aware of the existence and basic uses of the scientific investigative aids that are most generally available, thus aiding his initial observation and preservation of the crime scene. The opening chapter deals with the use of visual aids to investigation, such as photographs, casts, models, maps, and diagrams. Subsequent chapters deal individually with the following topics - fingerprint identification, document analysis, firearms evidence, tool mark comparisons, microanalysis, biological evidence, neutron activation analysis, and spectrographic voice identification. Also covered in separate chapters are the proper techniques for the employment of speed detection devices and the polygraph. The volume explains what the police officer must look for and do in collecting and preserving evidence to be submitted for scientific investigation. The FBI rules for handling physical evidence are appended.