Q4: Q4: FingerprintsFingerprints

What is a FingerprintWhat is a Fingerprint

Def:Def: Impression of the ridges of all Impression of the ridges of all or any part of the fingeror any part of the finger

Ridge:Ridge: Raised portion of the Raised portion of the epidermis on the palmar (palms and epidermis on the palmar (palms and fingers) or plantar (sole and toes)fingers) or plantar (sole and toes)

Grooves:Grooves: Indented portions Indented portions

between ridgesbetween ridges

What are Fingerprints What are Fingerprints Cont…Cont…

Ridges and Grooves are formed Ridges and Grooves are formed during the 4-5 month of the during the 4-5 month of the development of the fetus in the development of the fetus in the wombwomb Remain unchanged for the rest of your Remain unchanged for the rest of your

life except to enlarge during growthlife except to enlarge during growth No two people have the same No two people have the same

fingerprintsfingerprints Not even Identical TwinsNot even Identical Twins

Types of FingerprintsTypes of Fingerprints Latent Prints:Latent Prints: Not apparent to the naked Not apparent to the naked

eye (can’t be seen). Form from sweat of eye (can’t be seen). Form from sweat of the sebaceous glands of the body and waterthe sebaceous glands of the body and water 98% water98% water 2% oils 2% oils

Patent Prints:Patent Prints: Visible prints left behind in Visible prints left behind in some medium, such as blood, dirt, grease, some medium, such as blood, dirt, grease, etc.etc.

Plastic Prints:Plastic Prints: Impressed prints. Impressed prints. Indentations left behind in soft pliable Indentations left behind in soft pliable surfaces, such as clay, wax, paint, etc. surfaces, such as clay, wax, paint, etc.

PatternsPatterns

ArchesArches Represent only 5% of fingerprint Represent only 5% of fingerprint

patterns encounteredpatterns encountered 4% = Plain Arch4% = Plain Arch 1% = Tented Arch1% = Tented Arch

Arches = NO DELTA’sArches = NO DELTA’s

ArchesArches

Plain Arch Plain Arch Tented ArchTented Arch

LoopsLoops

65% of fingerprint patterns 65% of fingerprint patterns encounteredencountered

Loops = 1 DeltaLoops = 1 Delta Ridge enters from one side, touches Ridge enters from one side, touches

or crosses running line from the or crosses running line from the delta, and exits on the same sidedelta, and exits on the same side

Simple LoopSimple Loop

Loops vs. ArchesLoops vs. Arches

Types of Simple LoopsTypes of Simple Loops 2 different names are given to Simple Loops to 2 different names are given to Simple Loops to

classify which direction the Loop is pointing classify which direction the Loop is pointing tootoo Ulna Loop:Ulna Loop: Loop enters and exits in direction of Loop enters and exits in direction of

the pinky the pinky 60% 60%

Radial Loop:Radial Loop: Loop enters and exits in direction of Loop enters and exits in direction of the thumbthe thumb

Less common than Ulna LoopsLess common than Ulna Loops 5%5%

All depends on which hand the print comes All depends on which hand the print comes fromfrom

WhorlsWhorls

30% of fingerprints encountered30% of fingerprints encountered Whorls = 2 or more DeltasWhorls = 2 or more Deltas Plain Whorl (20%):Plain Whorl (20%):

When an imaginary line is made from When an imaginary line is made from Delta to Delta the line cuts across the Delta to Delta the line cuts across the ridges that create the inner pattern ridges that create the inner pattern area area

Plain WhorlPlain Whorl

Central Pocket WhorlCentral Pocket Whorl

Exactly like Plain Whorls but there is Exactly like Plain Whorls but there is one exceptionone exception

Imaginary line running from Delta to Imaginary line running from Delta to Delta does not cut across the ridges Delta does not cut across the ridges that create the inner pattern areathat create the inner pattern area

Central Pocket WhorlCentral Pocket Whorl

Side by Side ComparisonSide by Side Comparison

Double Loop WhorlsDouble Loop Whorls

Whorl that Whorl that consists of 2 consists of 2 separate and separate and distinctive loop distinctive loop formationsformations

The loops in the The loops in the core must core must comprise of comprise of separate linesseparate lines

Accidental WhorlAccidental Whorl

Consist of 2 or Consist of 2 or more delta’smore delta’s

Consist of 2 or Consist of 2 or more types of more types of patterns (except patterns (except plain arches)plain arches)

Freak patterns or Freak patterns or accidental accidental formationsformations

What print is this? (left What print is this? (left hand)hand)

Accidental WhorlAccidental Whorl

What Print is this? (left What Print is this? (left hand)hand)

Central Pocket WhorlCentral Pocket Whorl

What Print is this (left What Print is this (left hand)hand)

Plain WhorlPlain Whorl

What print is this? (left What print is this? (left hand)hand)

Radial LoopRadial Loop

What Print is This? (left What Print is This? (left hand)hand)

Double Loop WhorlDouble Loop Whorl

What Print is This? (Left What Print is This? (Left Hand)Hand)

Ulna LoopUlna Loop

What print is this? (Left What print is this? (Left Hand)Hand)

Tented ArchTented Arch

Ridge CharacteristicsRidge Characteristicsalso called Minutiae also called Minutiae

Fingerprints as EvidenceFingerprints as Evidence

There are no legal requirements in There are no legal requirements in United States on the number of United States on the number of ridge characteristics (ridge characteristics (MinutiaeMinutiae) ) that must match before deciding if that must match before deciding if the fingerprint belongs to a certain the fingerprint belongs to a certain individualindividual Standard is about 8-12 pointsStandard is about 8-12 points Legible Print has about 150-200 Legible Print has about 150-200

minutiaeminutiae

Henry-FBI Classification Henry-FBI Classification NumberNumber

1. Identify the presence of any 1. Identify the presence of any whorl patternswhorl patterns

2. Use the chart to assign a number 2. Use the chart to assign a number value to any whorls based on the value to any whorls based on the finger that the pattern is locatedfinger that the pattern is located

3. Complete the math problem3. Complete the math problem Its set-up as a fractionIts set-up as a fraction

Henry-FBI Classification Henry-FBI Classification NumberNumber

R. Index + R. Ring + L. Thumb + L. Middle + L. Little + 1 R. Index + R. Ring + L. Thumb + L. Middle + L. Little + 1 ==

______16 8 4 2 16 8 4 2 1______1______

R. Thumb + R. Middle + R. Little + L. Index + L. Ring + 1 R. Thumb + R. Middle + R. Little + L. Index + L. Ring + 1 ==

16 8 4 2 116 8 4 2 1

EXAMPLE: Lets suppose there is a whorl on EXAMPLE: Lets suppose there is a whorl on your left thumb, left little finger, and your your left thumb, left little finger, and your right little finger (with the rest of your right little finger (with the rest of your fingers having loops or arches)fingers having loops or arches)

Henry-FBI Classification Henry-FBI Classification NumberNumber

Here’s another Example. Try this on your own Here’s another Example. Try this on your own now.now.

R. Index + R. Ring + L. Thumb + L. Middle + L. Little + 1 =R. Index + R. Ring + L. Thumb + L. Middle + L. Little + 1 =

______16 8 4 2 1______16 8 4 2 1______ R. Thumb + R. Middle + R. Little + L. Index + L. Ring + 1 =R. Thumb + R. Middle + R. Little + L. Index + L. Ring + 1 =

16 8 4 2 116 8 4 2 1 Lets suppose there is a whorl on your right Lets suppose there is a whorl on your right

thumb, left index finger, left ring finger, and thumb, left index finger, left ring finger, and your left little finger (with the rest of your your left little finger (with the rest of your fingers having loops or arches)fingers having loops or arches)

Answer: Answer: 2/20 = 1/10 = 0.12/20 = 1/10 = 0.1

Fingerprints and the U.SFingerprints and the U.S

1924 1924 Identification Division of the Identification Division of the FBI was formedFBI was formed By 1946 it held 100 million fingerprint By 1946 it held 100 million fingerprint

cardscards Today: Over 250 million sets of Today: Over 250 million sets of

fingerprintsfingerprints 133 stacks as high as the Empire State 133 stacks as high as the Empire State

buildingbuilding

Significant Modern DatesSignificant Modern DatesUse of Fingerprints for Positive Use of Fingerprints for Positive

IdentificationIdentification 1684: 1684: Nehemiah Nehemiah

GrewGrew Published the first Published the first

paper on the paper on the ridge structure of ridge structure of skin of the fingers skin of the fingers and palmsand palms

English physician English physician and renowned and renowned botanistbotanist

Significant Modern DatesSignificant Modern DatesUse of Fingerprints for Positive Use of Fingerprints for Positive

IdentificationIdentification 1823: 1823: Jan E. Purkyne

Published his thesis Published his thesis discussing different discussing different fingerprint patternsfingerprint patterns

Did not mention use Did not mention use of fingerprints to of fingerprints to identify peopleidentify people

Czech physiologist Czech physiologist and professor of and professor of anatomyanatomy

Fingerprint Fingerprint HistoryHistory

1877: 1877: Sir William Herschel Sir William Herschel Used fingerprints to:Used fingerprints to:

Accompany signatures on various Accompany signatures on various documentsdocuments

Registered government pensioners' Registered government pensioners' fingerprints to prevent collection by fingerprints to prevent collection by relatives after a pensioner's death.relatives after a pensioner's death.

Prisoners on sentencing to prevent Prisoners on sentencing to prevent various frauds of avoiding serving a various frauds of avoiding serving a prison sentence.prison sentence.

Prior to this they used…Prior to this they used… BrandingBranding Chopping off of fingersChopping off of fingers Alphonse Bertillon Alphonse Bertillon Anthropometry: Anthropometry:

Study of body measurementsStudy of body measurements

Significant Modern Dates Significant Modern Dates Cont…Cont…

1880:1880: Henry FauldsHenry Faulds British doctor wrote papers British doctor wrote papers

discussing the usefulness of discussing the usefulness of prints and suggested we prints and suggested we record fingerprints with inkrecord fingerprints with ink

British doctor who British doctor who investigated whether or not investigated whether or not fingerprints always stay the fingerprints always stay the samesame

Subjected students to Subjected students to various testsvarious tests

Shaved fingertipsShaved fingertips AcidAcid Spanish FlySpanish Fly

Conclusion:Conclusion: Fingertips Fingertips always grew back the samealways grew back the same

Significant Dates Cont…Significant Dates Cont…

1892:1892: Sir Francis GaltonSir Francis Galton Studied dactyloscopy, Studied dactyloscopy,

anthropometry, eugenics, anthropometry, eugenics, meteorology, tropical explorermeteorology, tropical explorer

Cousins with DarwinCousins with Darwin 3 books about the probability of 3 books about the probability of

two persons having the same two persons having the same fingerprints. Made it acceptable fingerprints. Made it acceptable in courtsin courts

1 in 64 billion1 in 64 billion Paved the way for an Paved the way for an

classificationclassification

systemsystem

Significant Dates Cont…Significant Dates Cont…

1901:1901: Sir Edward HenrySir Edward Henry Director of first Director of first

Fingerprinting Bureau in Fingerprinting Bureau in LondonLondon

Devised the Devised the The Henry The Henry Classification SystemClassification System

His system allowed all sets His system allowed all sets of 10 prints be divided into of 10 prints be divided into 1,024 groups1,024 groups

Excellent for a time when Excellent for a time when there was not computers and there was not computers and we had to do this by handwe had to do this by hand

Fingerprinting HistoryFingerprinting History

1903: 1903: Alphonse Alphonse BertillonBertillon Father of Father of

AnthropometryAnthropometry Created methods to Created methods to

get fingerprints off of get fingerprints off of smooth surfacessmooth surfaces