Transcript Fingerprinting

Chapter 6
Fingerprinting (Saferstein- Video Jug) (new techniques-CBS)
History of Fingerprinting
1858- William Herschel
-1st official use of fingerprints
required natives of India to affix their
print to contract
1880- Dr. Henry Faulds
-1st to publish article suggesting ridge
patterns could be used for identification
1882- Gilbert Thompson
-1st to use fingerprints in the US
-added his print to US Geological
Survey document
1883- Alphonse Bertillon
-introduces anthropometry
-use of body measurements to ID
person

(1903- Will West / William West case is
noted as the demise of the Bertillon
Method of Identification. Two men, not
brothers, had the exact same
measurements but different
fingerprints. This incident happened at
Leavenworth Penitentiary in Kansas. )
Will West's Bertillon Measurements
178.5; 187.0; 91.2; 19.7; 15.8; 14.8; 6.6; 28.2; 12.3; 9.7
William West's Bertillon Measurements
177.5; 188.0; 91.3; 19.8; 15.9; 14.8; 6.5; 27.5; 12.2; 9.6; 50.3
1891- Dr. Juan Vucetich
-devised classification system still used
today in Spanish speaking countries
1st 10 print card
1892- Francis Galton
-published Fingerprints
-discusses pattern types, uniqueness &
permanence of prints
-devised 1st classification system
1897- Edward Richard Henry
-proposed classification system adopted
by most English speaking countries
1902- US 1st used fingerprints for NY Civil
Service Commission applicants
-1st time fingerprints used for ID of
criminals in England
1904- US penitentiary in Kansas & St.
Louis police dept. establish fingerprint
bureaus
1924 – Identification Division of FBI
established (national repository and
clearinghouse)
1933- Latent fingerprint section of FBI
established
1973- 1st phase of automated system
1999 - IAFIS- Integrated automated
fingerprint identification system (now
used) , also called AFIS
Now-over 250 million sets of prints on file
on cards (enough for 133 stacks the
height of Empire State building)
-over 55 million prints in the
computerized automated system
-FBI gets 50000 prints/day, 7 days/wk
Fundamental Principles of
Fingerprinting
1. A fingerprint is an individual
characteristic. No two fingers have yet
been found to possess identical ridge
characteristics
Ridge Characteristics (aka. Minutiae)
ridge endings, bifurcations, enclosures,
crossings, islands, and other ridge
details, which must match in two
fingerprints in order for their common
origin to be established
Individuality is established by comparing
identity, number and location of ridge
characteristics
-there are more than 150 individual ridge
characteristics on each fingerprint
(need 8-16 points of comparison to
establish individuality)
1-island
2-bifurcation
3-dot
4-ending ridge
5-bifurcation
6-island
7&8-bifurcation
9-ending ridge
10-island
2.
A fingerprint will remain unchanged
during an individuals lifetime.
-can’t change a print, scars leave
another link for comparison
Ex. Dillinger- Acid soaked- still make
out 14 pts. of comparison (p. 139 )
Skin Structure
Dermal papillae
1-2 mm beneath the skin surface
 Determines the ridge pattern
(developed as fetus-unchanged
through life)- start developing 2-3
months as fetus- fully developed by 6
months

Latent Prints

Made by deposit of oils and/or
perspiration from sweat glands on
surface (invisible to naked eye)
3. Fingerprints have general ridge
patterns that permit them to be
systematically classified
Loops
60-65 %
 Ridge lines that enter from one side of
the pattern and curve around & exit
same side, one delta
 Ulnar loop- opens toward little finger
 Radial loop- opens toward thumb

Whorls
30-35%
 Ridge lines are rounded or circular in
shape, have 2 deltas
 Types: plain, central pocket loop,
double loop, accidental

Plain
Central Pocket Double Loop Accidental
Arches
5%
 Ridge lines that enter the print from
one side and flow out the other side,
no deltas
 Types- plain or tented

Tented arch
Plain arch
Classification of Fingerprints
Henry Primary (FBI)
Classification
Converts ridge patterns into a series of
numbers arranged in a form of a
fraction
 Look for the presence of a whorl, if a
finger is a whorl substitute the
numbers for the terms of the fingers in
the formula

Henry Formula:
16
8
4
2
1
RI + RR + LT + LM + LL +1
RT + RM + RL + LI + LR +1
16
8
4
2
1
Ex. Whorl on Right Ring, right thumb
0+8+0+0+0+1
16+0+0+0+0+1
9/17
What is a 17/9?
Whorls on Right index, right middle
What is a 21/5?
Whorls on right index, left thumb and
right little
Mythbusters: Fingerprint
 Fingerprint Analysis
 Cartridge Cases

Automated Fingerprint
Identification System
AFIS
 Uses automatic scanning devices that
convert the image of the fingerprint
into digital minutiae that contains data
showing ridges & branches
 Can search set of 10 prints against
500,000 “10-print” cards in 8/10 sec.
 Video

Methods of Detecting
Fingerprints
Types of Crime Scene Fingerprints:
 Visible- made when a finger deposits a
visible material – such as dirt, blood
 Plastic – fingerprint impressed on a soft
surface (wax, gum)
 Latent – transfer of body perspiration
or oils
(visualizing latent prints depends on the
surface they are found on)
Methods of Detecting Latent Prints:
1. Powders (hard. Non absorbent
surface)
2. Chemicals:




Iodine (porous)
Ninhydrin (reacts w amino acids)-porous
Silver Nitrate (AgNO3)- sweat/saltsporous
Cyanoacrylate ester (super glue)- nonporous
3.
Laser
(Once visualized prints are photographed
or bagged if small or lifted if
immovable)