Kendall/Hunt Publishing Company 1 Dactyloscopy - The Study of Fingerprints History from 1850 to 1900 William Herschel - required Indians to put their fingerprints

Kendall/Hunt Publishing Company

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Dactyloscopy -The Study of Fingerprints

History from 1850 to 1900William Herschel - required Indians to put their fingerprints on contracts,

and used fingerprints as a means of identifying prisoners Henry Faulds - claimed that fingerprints did not change over time and that

they could be classified for identification

Alphonse Bertillon - proposed body measurements as a means of identification; termed anthropometry

Francis Galton - developed a primary classification scheme based on loops, arches, and whorls

Edward Richard Henry - in collaboration with Galton, instituted a numerical classification system

AnthropometryFirst systematic attempt

at personal identification

• Alphonse Bertillon in 1883– Anthropometry: system of precise body

measurements• Included detailed descriptions of the subject• Full-length and profile photographs• Accuracy of measurements were disproved

by the William West Case (Leavenworth Prison is 1903)

History of Fingerprinting

• Francis Galton– 1892: Published Finger Prints

• Described the anatomy of fingerprints and suggested methods for recording them

• Acknowledged that no two prints are alike and do not change throughout a lifetime

• Three pattern types– Loops, Arches, and Whorls

Fundamental Principles of Fingerprints

First Principle• A fingerprint is an individual characteristic. No

two fingers have yet been found to possess identical ridge characteristics

• Individuality of a fingerprint is not determined by its general shape or pattern but by careful study of ridge characteristics or minutiae

• Examples: bifurcation, enclosures, islands, ridge endings, short ridges, ridge crossings, deltas

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Minutiae - characteristics of ridge patterns

Ridge Characteristics - Minutiae

• Ridge ending – a ridge that ends abruptly


• Bifurcation – a single ridge that divides into two ridges.


• Eye & Enclosure – a single ridge that bifurcates and reunites a short time after to form a single ridge


Eye Enclosure

• Short ridge or island – a ridge that starts, travels a short distance and then ends


• Dot – an independent ridge with approximately equal length and width


• Spur or Hook – a bifurcation with a short ridge branching off a longer ridge


• Crossover & bridge – a short ridge that runs between two parallel ridges


• Delta – the point directly in front of the diverging ridges


• Core– the center area of a fingerprint/pattern


• Trifurcation– a single ridge that divides into three ridges.


Cicatrix- a scar


• Second Principle• A fingerprint remains unchanged during an

individual’s lifetime. Fingerprints have been designed by nature to increase grasp and to resist slippage and are formed in the fetal stage of development.

• Fingerprints are formed by:• Hills (Ridges): raised portions of the epidermis• Valleys (Grooves): lowered portions of the

epidermis• IT IS THE RIDGES THAT ARE INKED WHEN

FINGERPRINTS ARE TAKEN

How are Fingerprints Formed?

• The Dermal Papillae is the boundary between the epidermis (outer skin) and the dermis (inner skin).

• The shape of this boundary is wavy. This wave pattern determines the pattern of the fingerprint

and remains unchanged throughout your lifetime.

• Friction ridges, as they are called, can also be found on your palms, feet, and lips. They are not genetically controlled.

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• Epidermis– Outer layer of the

skin• Dermis

– Inner layer of the skin• Dermal papillae

– Layer of cells between the epidermis and dermis

– Responsible for determining the form and pattern of the ridges on the surface of the skin

Anatomy of the Skin

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Anatomy of the Skin

• Dermal papillae develop in the human fetus

• Ridge patterns will remain unchanged throughout life

• Enlarge during growth

• Fingerprint remains unchanged during lifetime

Leaving Your Mark• Skin ridges have a single row of

pores that open from the sweat glands.

• Perspiration is discharged through the pores and oils from the body collect in the ridges and valleys.

• Impressions from the fingertips are transferred onto a surface, leaving a fingerprint.– Latent fingerprints are deposited in

this manner and cannot be seen with the naked eye.


• Third Principle

– Fingerprints have general ridge patterns that permit them to systematically classified.

– L.A.W.S

LOOPA loop must have one or more ridges entering and exiting from the same side. Loops must have one delta.

Types

**Depends on which hand you are looking.

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Loop Vocabulary• Ulnar Loop: loop opens toward

little finger or the Ulnar bone.• Radial Loop: loop opens toward

the thumb or the Radius bone.– Type Lines: pattern area of the loop

surrounded by two diverging ridges– Delta: the point directly in front of the

diverging ridges—loops MUST have at least one delta

– Core: the center of pattern

**Photos are from right index print.

Ulnar Loop

Radial Loop

LOOP Types

ARCH

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An arch has friction ridges that enter on one side of the finger and cross/exit to the other side while rising upward in the middle. They do NOT have type lines, deltas, or cores.

Types

Plain

Tented

• Plain Arch-Ridges enter, wave or rise and exit smoothly

• Tented Arch-Ridges in the center thrust upward to give an appearance similar to a tent. Inside angle is smaller than 90 degrees

Plain Arch

Tented Arch

ARCH

WHORLA plain or central pocket whorl has at least one ridge that makes a complete circuit.

A double loop is made of two loops.

An accidental is a pattern not covered by other categories. Whorls have at least two deltas and a core.

Types

Plain

Central pocket

Double loop

Accidental

• Plain Whorl-One or more ridges form a complete revolution around the center

• Central Pocket Loop Whorl- Some ridges form a loop pattern which re-curves and surrounds a central whorl

Plain Whorl

Central PocketLoop Whorl

WHORL

• Draw an “imaginary” line between the two deltas in the plain and central pocket whorls. If some of the curved ridges touch the line, it is a plain whorl. If none of the center core touches the line, it is a central pocket whorl.

Plain Whorl

Central PocketLoop Whorl

WHORL

• Double Loop - Two separate loops are present, which sometimes surround each other. Sometimes called Double Loop Whorl (ying / yang)

• Accidental - Any pattern which does not conform to any of the previous patterns

Double Loop

Accidental


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LOOP

ARCH WHORL

Ulnar – 60%

Radial – 5%

Plain – 4%Tented –

1%

Plain – 20%

Other – 10%

Frequency of Patterns

Practice• Identify these prints and BE SPECIFIC! (These

pictures are if you are looking at the print of the right index finger.)

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Plain Arch Tented Arch Radial Loop Ulnar Loop

Plain Whorl Central Pocket Double Loop Accidental Whorl Whorl


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Comparison There are no legal

requirements in the

United States on the

number of points

required for a match.

Generally, criminal

courts will accept 8 to

12 points of similarity.

Taking Fingerprints• Fingers are rolled in ink left-to-

right, careful not to adhere too much ink to the fingertips

• The fingertips are then rolled left-to-right on a Ten-Print Card in the appropriate place for each finger

• A straight down print is then taken for each of the four fingers simultaneously and for each thumb and recorded on the Ten-Print Card


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The Automated Fingerprint Identification System - a computer system for storing and retrieving fingerprints

• Computer-scans and digitally encodes fingerprints based on minutiae of ridge endings and bifurications

• List of prints is generated then a fingerprint examiner confirms match *****

Established in the 1970s, AFIS enables law enforcement officials to:Search large files for a set of prints taken from an individualCompare a single print, usually a latent print developed from a

crime scene

AFIS


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By the 1990s, most large jurisdictions had their own system in place. The problem: A person’s fingerprints may be in one AFIS database but not in others.

IAFIS—the FBI’s Integrated Automated Fingerprint Identification System, which is a national database of all 10-print cards from all over the country

AFIS

Benefits of AFIS• Computer can make thousands of

accurate fingerprint comparisons in a second

• Can filter out imperfections in latent prints found at a crime scene

• Suspect lists are generated faster and investigators can spend more time focusing on suspects

AFIS

• http://www.youtube.com/watch?v=ZKi1CKTRCQM&feature=related

http://www.youtube.com/watch?v=ZKi1CKTRCQM&feature=related



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Kendall/Hunt Publishing Company 1 Dactyloscopy - The Study of Fingerprints History from 1850 to 1900 William Herschel - required Indians to put their fingerprints