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Bertillion system
first system used to identify criminals
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Alphonse Bertillion Anthropometry
physical measurements to identify individuals and who made this up
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portrait parle'
photographs and body measurements
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william hershel
required natives to sign contracts with an imprint of their hand, began lifelong study
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henry foulds
in scotland used fingerprints in a criminal setting freeing a suspect
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francis galton
publishes the book fingerprints and group patterns into loops, whorl, demenstrates no two prints are identical
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A fingerprint is an individual characteristic, no two fingers have yet to been found to possess identical ridge characteristics
1st fundemental principle of fingerprints
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level 1: flow of ridges, pattern type
level 2: minutiae (points)
level 3 shape/ structual of ridge units pores
indiviuality is determined by ( finger prints and levels)
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Analysis (level 1,2,3)
Comparison
Evaluation
Verification ( by someone else)
ACE-V methodology
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ACE-V methodolgy
assures validity and reliability
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a fingerprint remains unchanged during an idividuals lifetime
2nd fundemental principle of fingerprints
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fingerprints have general ridge patterns that permit them to be systamatically classified
3rd fundemental principle of fingerprints
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plastic prints
created when fingers touch material such as wet paint, oil films, putty, tape, dust
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Visible prints (patent prints)
created when fingers contaminated with foreign matter such as soot, blood, and ink touch a surface
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invisible (latent)
created when fingers with small amount of body oil and perspiration touch a surface
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surface smooth or textured
nature if material
how the object was handed
amount of concentration ( too much vs. too little)
suspect wearing gloves
environment conditions
Quality of print or failure to find prints at scene affected by
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powders
chemincals
LCV
iodine fuming
ninhydrine
SPR
physical developer
super glue fuming
methods of detecting
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powder
- goal is to provide contrast between the pront and the surface
- Black, white, magnetic silver, red, duel-contrast, floresent
apply small amount of .... to brush and then dust areas very smooth light strokes
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chemicals
amido black-... used with bloody prints reacts with proteins turns print blue black
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Leuco Crystal violet (LCV)
used with bloody prints, reacts with hemoglobin turns print to purple/violent color
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Ninhydrine
reacts to amino acids and is used with paper and cardboard turns prints purple blue heat applied to hasten
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Small Particle reagent (SPR)
adheres to the lipids and used to surfaces that are wet
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physical developer
silver nitrate based liquid with porous surface
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superglue fuming
- Cyanoacrylate nonporous surfaces such as metal tape, leather. heating of this in a chamber interacts with fingerprints
- prints are then enhanced in a chamber interacts with fingerprints then enhanced with powder or dye stains protect print and does not affect DNA (after)
- can do it on as small as a knife or as big as a car
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Laser and Alternative light sourse (ALS)
- prints (perspiration) with fluroses or glow and can be viewed with googles/filters
- photographs or enhanced with flourscent powders/dyes
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1. close-up photographs
2. collect them
3. tape life
4. gelatin lifters
5. casting material:accurtans microsil
How to collect of latent lifts
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Hair
cannot individualize a ......to any single head or body through morphology or structural characteristics
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1. anagen phase
2. catagen phase
3. telogen phase
3 stages of hair
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anagen phase
- initial growth up to 6 years
- follicular tag: piece of tissue surrounding the shaft that contains the richest sourse if DNA
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catagen phase
a transition stage between the anagen and telogen phases of hair growth
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telogen phase
the final growth phase in which hair naturally falls out of the skin
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follicular tag
a translucent of tissue surrounding the hair's shaft near the rot that contains the richest source of DNA associated with hair
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human vs. animal
species of animal
comparing questioned hair to standard
look @ color, length, diameter, presence of medulla distribution shape color intensity dyed/bleach
estimate of time sence dying or bleaching can look at hair for drug use.
Hair identification and comparison
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yes (pubic , beard , head)
Can we tell which body area hair comes from
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yes with caution
can we tell what race the hair came from
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age no expect infants
sex no styles preclude sex
Can we tell age and sex with hair
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yes
can we tell if hair is forcably removed
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nuclear DNA
- with root or follicular tag can individualize hair
- higher success during ANAGen phase
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mitochondral DNA
- cellular material outside of nucleus
- maternally inherited
- 2 cm needed for best results
- cant individualize
- diversity within human population permits exclusion
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presumptive
microscopic hair is .......
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need adequate number of standard/reference sample victim, suspect, other with access usually head or pubic hairs
need 50 from all areas of scalp 24 pubic hairs pulled or cut at skin line
sexual assult kits :combing of public hairs
collection of hair (general)
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tape lifts
tweezers with bindle
vaccum
collect item
collection of hair (at crime scene)
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Fibers
- mass production has limited the value of ....evidence
- rarely provide individualization
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torn edges (break match) fitted together can produce individualization
microscopic comparison of color and diameter
look at length straiations, pitting on surface, cross-sectional shape dyes chemical comparison use visible light
significance of fiber evidence depends on location number and nature of fibers
identification and comparison of fibers
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tape lifts
collect item and package seperately
tweezers and bindle
standards/reference samples
alternate light sourse (aLS)]
collection of fibers
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microscope serectmicrope
examine color surface texture color layer structure layer structure very important
number and sequence
break match can provide individuality
chemical analysis
gas chromatograph
paint identification and comparison
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tweezers in bindle (tape life)
scraped off with new razor blade (all layers)
collect item
carefully package clothing
standard/reference sample
undamaged area of car close to transfer
done to bare metal
1/4 inch square
collection of paint
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break match can provide individualization
general chemical composition is to uniform
look at density and refraction (class characteristics)
eliminate people
GLass identification and comparison
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radial fracture
a crack in a glass that extends outward like a spoke of a wheel from the point at which the glass was struck
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concentric fracture
a crack in a glass that forms a rough circle around the point of impact
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stress marks
shaped like arches and are perpendicular to one surface and curved parallel to the other
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opposite
edge of radital crack-perpendicular end is always .........the side of the force
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faces
edge of concentric crack perpendicular and always.... the surface where the force originated
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Radical cracks form a Right angle on the Reverse side of the force
3 R
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need standard/reference samples
collect from remaining glass in window or door
close to point of breakage
1 square inch
package in solid container
wrap clothing/shoes (burglary)
for direction of impact need to mark "inside: and outside
Glass collection
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cold filament (cold shock)
will break during contact
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Hot filament (hot shock)
will stretch and deform
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soil
- any disintegrated surface material natural or artifical that lies near the earths surface
- rocks, minerals, vegatation, asphalt, brick, fragments cinders
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