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  • How Police Find Latent Fingerprints—Part 3—Chemical Development Methods

    By: Administrator
    FBI Latent Print Hit of 2009 Part 2 of this series discussed the use of latent print development powders. This article will cover some of the most popular methods of chemical treatments. Latent print powders are of little use on porous surfaces such as paper, cardboard and raw wood; the reason being that a latent print is over 90% water, which is absorbed and dispersed in the surface. However, if prints are known to be fresh, regular black powder and magnetic powders may produce good results,...
  • A Brief History of Fingerprints

    By: Administrator
    The science of fingerprint identification, or dactylography, began nearly 4,000 years ago in the “Fertile Crescent,” the land between the Tigris and Euphrates Rivers in present day Iraq. King Hammurabi (1955-1913 BC) used finger seals on contracts and law officers of the day were authorized to secure fingerprints of arrested persons.   FBI Latent Print Hit of 2011 How Police Find latent Prints at Crime Scenes   A Brief History of Fingerprints The science of fingerprint...
  • Blood Spatter: What Does it Tell The Blood Spatter Analyst

    By: Administrator
    A significant number of high profile criminal cases have been prosecuted when blood spatter evidence was included among the physical evidence. By: Don Penven The interpretation of blood spatter was first mentioned in a paper written in the 1890s by a researcher at the Institute for Forensic Medicine in Poland, Dr. Eduard Piotrowski. His work, "Concerning the Origin, Shape, Direction and Distribution of the Bloodstains Following Head Wounds Caused by Blows." But it took nearly 50 years before...
  • Crime Scene Interpretation

    By: Administrator
    Crime Scene Interpretation by M/Sgt Hayden B. Baldwin, Retired Illinois State Police  The reconstruction of crime scenes is a miss nomenclature. You are in reality interpreting the information that you find by examining and processing the scene for evidence. This evidence will then permit you to make factual statements in regards to your findings. For instance, examining a footwear impression left at a scene you will be able to determine what direction the person was walking when that...
  • The Crime Scene Investigator

    By: Administrator
    A crime scene investigator may be called to a crime scene 15 minutes before Thanksgiving dinner or just as the kids start to open their Christmas presents. It isn't unusual for the call to come after the crime scene technician is asleep in bed, sometimes after having worked a 12-hour day What is a Crime Scene Investigator   It is a great pleasure and a privilege that we are able to include in the Crime Scene Training Blog a series of articles created by MSgt. Hayden B. Baldwin (Ret.). Please...
  • Crime Scene Processing Protocol

    By: Administrator
     by M/Sgt Hayden B. Baldwin, Retired Illinois State Police  In the endeavor of completing a work task certain criteria to complete the work task is needed. Crime scene processing is no different in that respect than to other work related tasks such as exchanging a motor in a car, painting a landscape scene or preparing a meal. There are certain tasks related to each work objective. In the field of crime scene processing several books have been written on what these tasks are and how they...
  • How Police Find Latent Fingerprints—Part 2—Latent Print Powders

    By: Administrator
    In Part 1 of this series we offered a description of what a latent print is, and an overview of latent print processing methods. This article will explain the various types of powders used to develop latent prints and their specific uses. One of the first known methods for developing latent prints used black powder made from lamp black or soot (carbon black) and white talc. The powder clings to the moisture content of the latent print as described in Part 1. Dark powders are used on...
  • How Police Find Latent Fingerprints—Part 1—What is a Latent Fingerprint?

    By: Administrator
    First a basic explanation: 1. A latent fingerprint is one that is generally not visible unless it is treated in some manner. The print itself is composed of moisture—mostly water—but it also contains small amounts of the constituents of perspiration (sweat), like amino acids, choline, sodium and potassium salts and urea.   2. The palms of the hands and soles of the feet are covered with friction ridges, and these ridges have sweat pores along their surface. These two areas have one...
  • Law Enforcement and Latent Fingerprints—How Do They Find Them at Crime Scenes

    By: Administrator
    The wildly popular TV show, “CSI-Crime Scene Investigation” has changed the public’s view on how crimes are investigated and solved. In a sense this show has accomplished two points: 1.  It has given the public first hand information about the tools and procedures that crime scene investigators use to solve crimes. 2. It has given the public unrealistic expectations in believing all law enforcement agencies should be able to catch the criminal in just 42-44 minutes. Budget constraints...
  • Crime Scene Investigation

    By: Administrator
    by M/Sgt Hayden B. Baldwin, Retired Illinois State Police  The reconstruction of crime scenes is a miss-nomenclature. You are in reality interpreting the information that you find by examining and processing the scene for evidence. This evidence will then permit you to make factual statements in regards to your findings. For instance, examining a footwear impression left at a scene you will be able to determine what direction the person was walking when that impression was made. Therefore...
  • Blood Spatter and Newton's Third Law

    By: Administrator
    It's the little details that trip up the criminal every time. DR. DOUG HANSON   dougmh@comcast.netdougmh@comcast.net Forensics Contributor Officer.com Dr. Tom Harper thought he had committed the perfect crime. He had shot his wife in a manner that should have left the bullet hard to find and identify. Then he had repeatedly stabbed her dead body with a kitchen knife, and after wiping off any fingerprints, dropped the knife in their backyard. Nearby, he made several impressions in the...
  • The Crime Scene Training Blog--Crime Scene Investigation Overview

    By: Administrator
    Thank you for visiting us. The intent of this blog is to provide the most comprehensive, up-to-date training in crime scene investigation available on the Internet today. Present plans include our making at least one post per week. Once we are up and running, and the interest is there, we will add additional posts with greater frequency. After a thorough search for information on actual crime scene training sites we found that they are few and far between. Most of what is available are in...