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Interpretation, Collection and Preservation of Glass Fragments

Monday, 26 October 2009 09:21 Katherine Steck-Flynn Physical Evidence - Trace Evidence

By Kathy Steck-Flynn

A man is found dead in an abandoned house. Upon examination the medical examiner finds that the man was killed by a single gunshot to the head. Three local teens where observed near the house two days earlier. They are picked up and questioned by police. When pressured, the teens admit to having stolen one of the boys' father's guns. They had taken turns shooting at the windows of an abandoned house.

The teens admit that John shot the gun first, then Jay and last was Fred. At the scene the investigators find three bullet holes in a window. They analyze the angle of each bullet hole in relation to the victim and find that the bullet which passed through the far right side of the window pane is the one which fatally wounded the man.

It is up to the investigators to determine the order of the shots. This will tell them which boy fired the fatal shot and allow the investigators to work out what the charges will be against the shooter. Examination of the fractures in the glass will tell them this.

Forensic Palynology

Sunday, 20 September 2009 20:02 Daryl W. Clemens Physical Evidence - Trace Evidence

PALYNOLOGY: The branch of science concerned with the study of pollen, spores , and similar palynomorphs, living and fossil. Term suggested by Hyde & Williams (1944). Etymol. Greek "to strew or sprinkle", suggestive of "fine meal" cognate with Latin pollen, "fine flour, dust."
-Definition from The University of Arizona

For futher information on Forensic Palynology you can contact Vaughn Bryant at:
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More information can also be found at these websites:
Dallas Mildenhall's page
Dr. Terry J. Hutter
University of Arizona
Lynne Milne

Last Updated on Sunday, 20 September 2009 20:11

Forensic Palynology in the United States

Sunday, 20 September 2009 19:58 Vaughn M. Bryant, Jr Physical Evidence - Trace Evidence

Vaughn M. Bryant, Jr.
Palynology Laboratory
Texas A&M University
College Station, Texas 77843

Dallas C. Mildenhall
Institute of Geological and Nuclear Sciences
P.O. Box 30368
Lower Hutt, New Zealand

Introduction

The term "forensic palynology" is rarely used in the United States. Forensics pertains to evidence used in courts of law. Palynology is the term first used by Hyde and Williams (1944) for the collective study of pollen grains and spores. Years later, the discipline of palynology was expanded to include the study of a number of other acid-resistant microorganisms as well.

Today, the science of forensic palynology traditionally focuses on legal evidence derived from the study of pollen and spores, both fossil and modern. In its broader application, the field of forensic palynology also includes legal information derived from the analyses of other palynomorphs such as dinoflagellates, acritarchs, and chitinozoans. However, in most sampling situations forensic palynologists rarely encounter these other types of acid-resistant palynomorphs because most are marine and many are restricted only to fossil deposits.

Forensic Palynology: A New Way to Catch Crooks

Sunday, 20 September 2009 19:55 Vaughn M. Bryant, Jr Physical Evidence - Trace Evidence

Abstract

Studies of palynomorphs trapped in materials associated with criminal or civil investigations are slowly gaining recognition as valuable forensic techniques. Today, the country of New Zealand leads the world in the use of forensic palynology, and the acceptance of this type of evidence in courts of law. To illustrate how important, and diverse forensic palynology has become, we have briefly examined a number of actual circumstances where these types of techniques have proven useful. In most of these cases the palynomorph data were an important factor in either solving the case, or they were used to identify and link a suspect to the scene of a crime. We also discuss some of the strengths, and weaknesses, of using forensic pollen data, and why we feel this technique is still neither widely accepted nor used in most of the countries of the world.

Condom Trace Evidence: A New Factor in Sexual Assault Investigations

Sunday, 20 September 2009 19:43 Robert D. Blackledge Physical Evidence - Trace Evidence

By Robert D. Blackledge, M.S.
Mr. Blackledge is senior chemist at the Naval Criminal Investigative Service Regional Forensic Laboratory in San Diego, California.

This Article Originally Appeared in the FBI Law Enforcement Bulletin, May 1996.

(Offenders are changing the nature of sexual assault investigations by wearing condoms.)

In an age filled with potentially fatal sexually transmitted diseases, more and more individuals practice safe sex. Even perpetrators of sex crimes have begun to wear condoms.¹ It is not likely that a fear of disease prompts this behavior. Rather, just as a burglar dons gloves to avoid leaving fingerprints, sexual offenders now wear condoms to avoid depositing seminal fluids.

Forensic experts typically identify sexual assault offenders by examining seminal fluid residues for sperm, proteins, blood grouping factors, and DNA profile. When sexual assailants use condoms, however, assuming no leaks or spills, this valuable evidence gets trapped inside the condom, which investigators may never recover. The same can be said for any traces from the victim--including vaginal cells, blood, and saliva--that otherwise might have been transferred to the assailant's penis.

Nevertheless, when assailants use condoms, they leave behind other valuable evidence.

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