Gingersmith W09 HND CJE1640 20131210-2 pptx [Autosaved]

five types of trace evidence.

TRACE EVIDENCE

Hair is a small thin type thread form which covers a body the pubic region.Hairs a

re part of the

scalp

which is calle

d follicles

which are remo

ved and have

a tag on the e

nd of the hair

used for indi

vidual

identification

.Animal hairs – classified into three (3) major groups by microscopic appearance:1. Deer and antelope family are distinguished by their isodiametric scales and wineglass-shaped roots.2. Commercial fur animals, such as rabbits and minks, are distinguished by their banded, serial ladders or vacuolated medulla structures.3. Domestic animals are distinguished by their amorphous medullae and characteristic root shapes.

Examine hair: using a microscope for:

SpeciesLocation of body from which the hair came.How the hair was lostAge of personRace of personTreated hair,(permed or colored)Broken or burnedAnd hair removed post mortemThis process is used to profile the suspect or victim. After presumed the Forensic DNA testing, which results in solving a crime.

The problem with fiber evidence

is that fibers are not unique.

Unlike fingerprints or DNA, they

cannot pinpoint an offender in

any definitive mannerFibers are gathered at a crime scene with tweezers, tape, or a vacuum. They generally comes from clothing ,carpet wigs. The determine the natural, manufactured aspect of the evidence.

Generally, the analyst gets only a limited number of fibers to work with sometimes only one. Whatever has been gathered from the crime scene is then compared against fibers from a suspect source, such as a car or home, and the fibers are laid side by side for visual inspection through a microscope

In short, the fiber analyst compares shape, dye content, size, chemical composition, and microscopic appearances, yet all of this is still about "class evidence.“ Even if fibers from two separate places can be matched via comparison, that does not mean they derive from the same source, and there is no fiber database that provides a probability of origin

Introduction

PAINT C

AN BE AT

A CRIME

SCENE O

R

LEFT AT

A ACCIDE

NT TRANS

FERRED

FROM ANO

THER VEH

ICLE OR

OBJECT

USED IN

THE CRIM

E..

Paint sample analysis Paint samples undergo a number of different steps for comparative analysis. The analysis often begins with a microscopic examination of the paint to determine the color and number of layers contained in the sample. Reference and crime scene samples that match after microscopic analysis are subjected to instrumental analysis. Samples a few millimeters in length can be used for this analysis. Matching paint samples, the evidence collected and compared to a reference sample, indicate that the samples came from the same source

The lab then put the glass fragmentsthrough ICP–AES analysis. A quantitativeanalysis of the fragments found that theglass pieces

The lab then put the glass fragmentsthrough ICP–AES analysis.

•Place large glass fragments in boxes. Separate individual pieces with cotton or tissue to prevent breakage and damaged edges during shipment. Seal and mark the box containing them

•Place small glass fragments in paper bindles, then in coin envelopes, pill boxes, or film cans which can be marked and completely sealed.

: If the broken window is small, send the whole window or all glass remaining to the Laboratory.glass remaining in the shell should be recovered. If it is suspected that a new glass has been installed, this should be removed and a careful examination made for small chips remaining in the shell from the previous lens which is broken. In such cases, also submit the new lens to the Laboratory.

Most soil analysis consists of comparing two or more samples by their mineral content, color, and density. The presence of pesticides and herbicides have also been used in soil comparison.Clothing or shoes should be dried and then placed in individual paper bags.Known soil samples should be collected as follows:one sample at the point of suspected origin;one sample on each side about one foot away.one sample on each side about ten feet away

These samples should be taken from approximately the same depth as the questioned sample. If a shoe print is one quarter of an inch deep, do not sample an inch or more in depth. The zip-lock plastic bags in the trace kit are convenient for such a sample. A bag about half-full of soil would provide an adequate sample

TRACE EVIDENCE• LOOKING OVER THE 5 DIFFERENT TRACE EVIDENCE DETERMINES WHO,WHAT,WHERE AND WHEN AN ACCIDENT OR CRIME WAS PERFORMED AND WHAT DEVICE WAS USED TO COMMITT THE CRIME.

• Trace evidence is used to complete a story of where the person was or is.

• Performing lab tests by microscope or by pictures or using special crime lab tools to collect the evidence with out contaminating the evidence.

Referenceshttp://cte.unt.edu/content/files/_LPSCS/LPSCS_curriculum/ForensicSci/06.01H%26F/06FSCI-HandF.pdfhttp://www.crimelibrary.com/criminal_mind/forensics/trace/3.html

https://www.ncjrs.gov/pdffiles1/jr000249b.pdf

http://www.crime-scene-investigator.net/collect.html#5