Transcript Prints Impressions - Ardsley Union Free School District

The World of Prints and Impressions
History
• Chinese, 3000 years ago, fingerprints on legal
documents
• 8th Century Japan-Legal Documents
• 14th Century Persia-Government Papers
• Ancient Rome-Bloody handprint linked to killer
• William Herschel 1800s (English civil servant
working in India) required Indians “sign”
documents with fingerprint.
• Henry Fauld 1800s (Scottish physician)
Fingerprints important in criminal investigations
History
• Francis Galton (1892) Published
“Fingerprints”-Science of Fingerprints
• Bertillon System supplemented with prints
• Sir Richard Henry (1897)-Developed
classification system and means of
accusation and filing.
• Bertillon System ditched with William West
Case (1903)-Fingerprints used in U.S.
Prisons
Flawed Bertillon System
Flawed Bertillon System
History
• 1900s fingerprints used on civil service
applications
• Mid 1900s used by police forces
What is a fingerprint?
Latent Prints=Invisible Prints
When you touch
something, you leave
perspiration, oils, amino
acids
Skin Ridge Purpose
Skin Ridge Purpose
• Provide Firm Grasp
• Resist slippage of feet
Principles of Fingerprints in
Forensics
1. No two people have the same prints
(millions of prints collected over 90
years)
2. Fingerprints are genetic, develop as
fetus and remain the same for life and
sometime after death
3. Fingerprints have patterns that allow
systematic classification
Ridge types
65%
5%
30%
150 Individual ridge characteristics/
fingerprint
Minutia=Ridge Characteristics
Sub classifications
Can You Change Fingerprints?
Can You Change Fingerprints?
• Not all patterns on hand!
• Needs wound down 2millimeters into skin
• Much scaring making you more
individualistic
John Dillinger
SCAR
TISSUE
Before Acid
After Acid
Henry System of Classification
R. Index
R. Ring
R. Thumb
R. Middle
L.Thumb
L. Middle
L. Little
R. Little
L. Index
L. Ring
•
Step 1: Set up these fractions
•
Step 2:
Whirls 1st Column fingers=16
2nd Column Fingers= 8
3rd Column Fingers= 4
4th Column Fingers= 2
5th Column Fingers= 1
•
Step 3: Tally Numbers
Henry System of Classification
• Example
– Suppose right index is whorl
– Suppose right middle is whorl
– All others are loops
16+0+0+0+0+1 = 17
0+8+0+0+0+1 =
9
Fingerprint Collection-Ink
Fingerprinting-Digital
AFIS
Search Speed= Minutes to search millions of prints
Fingerprints and Crimes
• Visible Prints
– Blood
– Paint
– Grease
– Ink
• Plastic prints
– Impressions in putty, wax, soap dust
• Latent Prints
– Hard-to-see remnants of perspiration and oils
Latent Fingerprint Development
• If hard, nonabsorbent
surface ex. Glass, tile
etc
– Fingerprint powders
– Soft brush
– Powder sticks to
perspiration
Latent Fingerprint Development
• If soft, absorbent
surface (ex. Paper,
cloth)
– Iodine crystal fuming
– Crystal undergo
sublimation
– Not permanent
development
– Gold-brown
development
– Mech. Unknown
Latent Fingerprint Development
• If soft absorbent
surface
– Ninhydrine Spray
– Reacts with amino
acids in perspiration to
produce purple
development
Latent Fingerprint Development
• Nonporous surfaces
(metals, tape, leather,
plastic bags
• Super Glue Fuming
– Cyanoacrylate fumes
– Produces white print
Latent Fingerprint Development
• Lasers and
Fluorescence
– Natural fluorescent
components in sweat
that can be enhanced
with chemicals and
observed with laser
light
Latent Fingerprint Development
• Alternate light source
( quartz halogen,
xenon)
– Focused light along
fiber optic cables
Preservation of prints
Preservation of prints
• Lifting Prints
Footnote
“Cancer patient held at airport for missing
fingerprint” (Reuters News Service)
• Side-effect of cancer drug
• palms or soles of the feet and the skin can peel,
bleed and develop ulcers or blisters -- or what is
known as hand-foot syndrome
Lip Prints
• Lip print lands Peeping Tom in jail
The Associated Press
• NEWPORT NEWS, Va. (AP) - This peeper's pucker landed him in
jail.
• Robert Neal Smith, 41, was sentenced to five months in jail Friday
after pleading guilty to peeping into his neighbor's windows. He was
charged with five counts of being a Peeping Tom after his lip prints
matched ones left on a window in August.
• Police had lifted the impression in September and obtained a search
warrant for Smith's lip marks. The state crime lab claimed the two
were a match.
• Smith told the General District Court judge he was drinking heavily
when he peeped into his neighbors' homes. At one point he was
chased by a woman's husband and another woman caught him
tampering with her window screen.
Lip Prints
• The five basic types
of lip prints used by
forensic scientists
are:
Lip Prints
• Cheiloscopy=study of lip prints
• Ancient Egyptians used henna to paint lips a
reddish purple hue
• Used mercuric plant dye called fucus for lip
rouge
• Can extract DNA from lip prints
• Lipsticks appeared first in the city of Ur near
Babylon 5000 years ago
• Lipstick first mass produced in tubes in 1915
• Differences found between man and women lip
prints
Foot Prints
Feet
Most of the time they are
impressions of feet and
not prints
Shoe Impressions
• What can we tell?
– Shoe type
– Shoe size
– Show wear patterns
Wear Patterns
- Toe or heal walker
activity of wearer
- Body Weight
surface they walk on
- Walk with feet inwards or outwards
unique holes/cuts/debris in shoe
-
What material can shoe
impressions be left in?
Locating Shoe Prints
Often found near:
- The actual point of occurrence of the crime
- The route through the points of entry/exit &
the crime scene
- Exterior areas
How common are Shoe Prints?
Combination of floor surface and condition
of footwear determines likelihood of a foot
print.
Likelihood of a Shoe Print
Shoe Impressions
• Can leave
impressions in dust
• Photograph
• Electrostatic lift
– Overlay dust with
mylar film sheet
Shoe Impressions
• Can leave impressions
in soil
• Photograph
• Make a cast with dental
stone
Shoe Impressions
• Can leave shoeprint
in snow
• Photograph
• Spray with 3 coats of
Snow-Print Wax
• Cast with Dental
Stone
Tire Impression
• What can we tell?
– Tread style=tire model
– Tread width=tire model
– Distance of left tires
from right tires (Track
Width)
– Manufacturer of tire
and make and year of
vehicle
Teeth Impressions
• Can be left in food,
gum and skin
Teeth Impressions
• Connect suspect to
bite mark: