aim: how was fingerprinting developed in forensic science? do now: are fingerprints individual or...

• AIM: How was fingerprinting developed in forensic science?

• DO NOW: Are fingerprints individual or class evidence? EXPLAIN YOUR ANSWER.

• HOMEWORK: Textbook read 72-73 and 76-77(Anatomy of a fingerprint). What are friction ridges and where are they found?

Monday 11/17/14• AIM: How are fingerprints developed?• DO NOW: 1- Take out your lab from Friday make

sure you answered the analysis questions EXCEPT 3 and 7

• 2- Read the Will West article and answer the following: 1- Who is William West?

• 2- Who is Will West• 3- Why are the “West Brothers” forensically

important• HW: Textbook page 100 questions 7-10. • QUIZ FRIDAY!

DactyloscopyThe study of fingerprints

Historically William Herschel—required Indians to put their fingerprints on

contracts, and also 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 Juan Vucetich—developed a fingerprint classification based on

Galton’s that is used in Spanish-speaking countries

William and Will west

What is a fingerprint?

• Skin has an outer layer (epidermis) which has ridges projecting inward, and an inner layer (dermis) which has projections pressing into the spaces between ridges

• A fingerprint is a pattern made by the friction ridges, which is left behind due to sweat and oil that sticks to them.

• Fingerprints form during the fetal stage of development.

http://www.smithsonianmag.com/video/Where-Do-Fingerprints-Come-From.html

When do they form?

• In early embryonic development & remain constant

What determines fingerprints?

• DNA - Genes• & environmental

forces: pressures within the womb and contact with the amniotic fluid

Thursday 11/19/14

• AIM: How are imprints individual pieces of evidence?

• DO NOW: Explain how fingerprints are formed• HOMEWORK: Textbook read 72-73 and 76-

77(Anatomy of a fingerprint). What are friction ridges and where are they found?

DONOW ANSWER

• DNA controls formation of epidermis and dermis

• The pressure on the amniotic fluid finalizes the ridge pattern

Formation of fingerprints• Skin layer growth

– 3-4 month– Middle layer of skin buckles and folds

creating the first ridges

• Creation of ridges– fetus touches surrounding structures, exact

position in the womb and the density of the womb's amniotic fluid determine how every individual ridge will form

• Ridge patterns: 6 months– The ridges on a fetus's fingertips have

formed three main patterns categorized as arches, loops and whorls

• Fingerprint characteristics– two common characteristics found in every

fingerprint: ridge end and bifurcation– The sequences of ridge end and bifurcation

characteristics are different in every fingerprint

13

Anatomy of Fingerprints• 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

Fundamental Principlesof Fingerprints

A fingerprint is an individual

characteristic.

A fingerprint will remain

unchanged during an

individual’s lifetime.

Fingerprints have general

characteristic ridge patterns

that permit them to be

systematically classified.

Fingerprint principle 1• A fingerprint is an individual characteristic • no two fingers have yet been found to posses

identical ridge characteristics

Principle 2

• Fingerprints have general ridge patterns that permit them to be systematically classified

Chapter 4

Thursday 11/20/14 AIM: how are fingerprints classified? DO NOW: Explain why each of your ten

fingerprints are different When do fingerprint patterns form? What are the three possible fingerprint

patterns HW: Text page 100 questions 3-10

Fingerprint Ridges

• Give skin traction for picking up items.• The fine lines curve, circle, and arch.• Valleys - grooves or furrows • Hills - friction ridges

Fingerprint Pattern• Pores on the ridges• Discharge perspiration

from the sweat glands• Sweat mixed with oil

can leave a latent invisible fingerprint

Other Prints

Ears—shape, length and width

Voice—electronic pulses measured on a

spectrograph

Foot—size of foot and toes; friction ridges on the foot

Shoes—can be compared and identified by type of

shoe, brand, size, year of purchase, and wear pattern.

Kendall/Hunt Publishing Company 20

Other Prints

Palm—friction ridges can be identified and may be used against suspects.

Chapter 4

Other Prints

Footprints are taken at birth as a means of identification of infants.

Chapter 4

Other Prints

Lips—display several common patterns

Short vertical lines Short horizontal lines Crosshatching Branching grooves

Chapter 4

Other Prints

Teeth—bite marks are unique and can be used to identify suspects. These imprints were placed in gum and could be matched to crime scene evidence.

Chapter 4

Other Prints

The blood vessel patterns in the eye may be unique to individuals. They are used today for various security purposes.

Chapter 4

Assessment

Create a list of each individual print.

26

Digital Storytelling - Fingerprint Analysis - YouTube

Kendall/Hunt Publishing Company 27

Chapter 4

Characteristics of fingerprints

Human population fingerprint distribution

• Loops: 65%• Whorls: 30%• Arches: 5%

FINGERPRINT IDENTIFICATIONFINGERPRINT IDENTIFICATION

Table 4.2 Frequency of fingerprints Loops WhorlsArchesUlnar radial plain other plain tented60% 5% 20% 10% 4% 1% loops = 65% whorl=30% arches =5%

Table 4.2 Frequency of fingerprints Loops WhorlsArchesUlnar radial plain other plain tented60% 5% 20% 10% 4% 1% loops = 65% whorl=30% arches =5%

Chapter 4

Arch

An arch has friction ridges that enter on one side of the finger and cross to the other side while rising upward in the middle.

Types Plain- the arch is mild Tented- the arch is

spiked upward

Plain arch

Tented arch

Loop

A loop must have one or more ridges entering and exiting from the same side it began.

Loops must have one delta (a“Y” pattern from diverging ridges)

Types Radial--opens toward the thumb Ulnar--opens toward the “pinky” (little

finger)

Which type of loop is this, if on the right hand? Left hand?deltaΔ

Whorl

A Whorl has a minimum of 2 deltas.

Types Plain- 2 symmetric deltas and a

complete ridge circuit (circular in pattern)

Central Pocket- 2 asymmetric deltas, one side appears to be stretched

Double Loop- 2 loops and 2 deltas Accidental- a whorl that does not fit

the 3 above pattern types

36 Plain whorl

Monday 11/24/14

AIM: what are the general fingerprint patterns?DO NOW: Is this the left or the right hand?What type of loop is this and how do you know?HW: text read page 80-81. Explain the HENRY classification system and how it works.

What is a delta and how do they relate to fingerprint patterns?

Arches NO deltas

ArchesArches are the simplest type of fingerprints that are formed by ridges that enter on one side of the print and exit on the other. No deltas are present.

Plain ArchRidges enter on one side and

exit on the other side.

Tented Arches Similar to the plain arch,

but has a spike in the center.

Spike or “tent”

Loops• Must have one

delta

41

LoopsLoops must have one delta and one or more ridges that enter and leave on the same side. These patterns are named for their positions related to the radius and ulna bones.

Delta

Ulnar Loop (Right Thumb)

Loop opens toward right or the ulna bone.

Radial Loop (Right Thumb)

Loop opens toward the left or the radial bone.

NOTE: On the left hand, a loop that opens to the left would be an ulnar loop, while one that opens to the right would be a radial loop.

Whorls: 2 deltas

WhorlsWhorls have at least one ridge that makes (or tends to make) a complete circuit. They also have at least two deltas. If a print has more than two deltas, it is most likely an accidental.

Draw a 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 Pocket Whorl

Whorls – Part 2

Accidental Whorl

Accidental whorls contain two or more patterns (not including the plain arch), or does not clearly fall under any of the other categories.

Double Loop Whorl

Double loop whorls are made up of any two loops combined into one print.

Delta

Delta

Central Pocket Whorl

46

Double Loop (whorl)

47

Accidental whorl

48

http://on.aol.com/video/how-to-

determine-fingerprint-patterns-72416331

Kendall/Hunt Publishing Company 49

Determining fetal environment

• The more symmetrical your fingerprints the more stable the amniotic environment

Kendall/Hunt Publishing Company 50

• Skin cells regenerate every 2 weeks

• If the friction ridge is not steep, the underlying skin pattern is shown

• White lines in ridge patterns represent diet pattern

• Many white lines indicate celiac disease 51

Tuesday 11/25/14

• AIM: how are fingerprints analyzed?• DO NOW: 1- What are the 3 general

fingerprint patterns?2- How can you identify a specific fingerprint pattern?HOMEWORK:text read pages 83-84

Kendall/Hunt Publishing Company 52

• Peter Griffiths

56

Fingerprint Identification

• The uniqueness of a fingerprint can be determined by the pattern of ridges and valleys as well as the minutiae points.

• Minutiae points are local ridge characteristics that occur at either a ridge bifurcation or a ridge ending.

57

Ridge Characteristics

Minutiae—characteristics of ridge patterns

Ridge ending Short ridge Dot or fragment Bifurcation Double bifurcation Trifurcation Bridge Island Enclosure Spur

Kendall/Hunt Publishing Company

On your computer paper

Thumb Index Middle Ring Pinky

Right Hand

Ridge pattern

LeftHand

Ridge pattern

Monday 12/1/14

• AIM: How can we observe our fingerprints?• DO NOW: Next slideHOMEWORK: Sticky fingers handout questions 1-5 page 3 and 1-3 page 4

Monday 12/1/14How would you describe each print?

What percentage of the population has each pattern

Arch Whorl Loop

1 2 3

Steps for Fingerprinting • Height – Fingerprinting surface should be 39

inches or 3 feet from floor• Clean fingers with alcohol swab – why?• The individual should stand to the right and rear of

the person taking the fingerprints in front of the card

Rolling Prints

Identify each fingerprint pattern.

?A B

CD E

Right Hand

Left Hand

Left Hand

Right Hand

Right Hand

Tuesday 12/2/14: On a separate sheet of paper answer

1. Identify the following prints as a loop, whorl or arch.

a b c d e

2. ___________is the study of fingerprinting.3. The two layers of the skin are the ______________ and the _______________.4. Fingerprint ridges form as a result of dermal __________________.

Wednesday 12/3/14

• AIM: How can we describe some characteristics of fingerprint patterns?

• DO NOW:1. How is it possible that identical twins have different fingerprints?

• 2-Do you think it’s possible to eliminate your fingerprints? Explain.

• HOMEWORK: Handout questions 1-12. You can use chapter 4 in the textbook to help.

Are fingerprints class or individual evidence EXPLAIN

Fingerprint patterns loop, whorl, arch are class evidence

Specific minutiae patterns are individual evidence

Comparison

• Individuality is determined by its RIDGE CHARACTERISITICS or MINUTIAE.

• Prints taken from the scene of a crime must show areas of commonality with a known set of prints to get a conviction

• Core: center where pattern begins• There are no legal requirements

in the United States on the number of points

• Generally, criminal courts will accept 8 to 12 points of similarity.

Kendall/Hunt Publishing Company 70

Fingerprint Minutiae

How are fingerprints compared?How are fingerprints compared?

A. Fingerprints are compared by noting the ridge pattern on two prints to determine whether or not they match.

B. The minutiae characteristics are then comparedC. An identification is established when a number of

these characteristics occupy the same relative position on the two prints.

A. Fingerprints are compared by noting the ridge pattern on two prints to determine whether or not they match.

B. The minutiae characteristics are then comparedC. An identification is established when a number of

these characteristics occupy the same relative position on the two prints.

FINGERPRINT IDENTIFICATIONFINGERPRINT IDENTIFICATION

How to Compare Fingerprints - The Basics - YouTube

RIDGE CHARACTERISTICS (Minutiae) RIDGE CHARACTERISTICS (Minutiae)

COMMONCOMMON OCCASIONALOCCASIONAL RARERARE

Ending RidgeEnding Ridge

Bifurcation or fork

Bifurcation or fork

DotDot

Eye or EnclosureEye or Enclosure

“T” Junction“T” Junction

Short RidgeShort Ridge

TrifurcationTrifurcation

Ridge CrossingRidge Crossing

Row of DotsRow of Dots

74

Fingerprint Basics (minutiae)

Bifurcation Ridge ending

dotDouble bifurcation

75

Fingerprint Basics (minutiae)

Opposed bifurcation

Island (short ridge)

Hook (spur) Lake (enclosure)

76

Fingerprint Basics (minutiae)

Ridge crossing

trifurcation

Opposed bifurcation/ridge ending)

Bridge

RIDGE CHARACTERISTICS MAGNIFIEDRIDGE CHARACTERISTICS MAGNIFIED

Points 1, 2, 4, 5 are Ending RidgesPoints 1, 2, 4, 5 are Ending Ridges

Points 8, 10, 11 are BifurcationsPoints 8, 10, 11 are Bifurcations

Point 7 Short RidgePoint 7 Short Ridge

Points 3 and 9 are DotsPoints 3 and 9 are Dots

Point 6 is an Enclosure (IEYE)Point 6 is an Enclosure (IEYE)

11

22

44

55

88

10101111

99

77

33

66

FINGERPRINT IDENTIFICATIONFINGERPRINT IDENTIFICATION

Henry Classification system• Developed a method of classifying fingerprints. • modified by the FBI that allowed all set of 10

fingerprints in the world to be divided into 1024 groups.

Table 4.2 Frequency of fingerprints Loops WhorlsArchesUlnar radial plain other plain tented60% 5% 20% 10% 4% 1% loops = 65% whorl=30% arches =5%

Henry Classification system• Developed a method of classifying fingerprints. • modified by the FBI that allowed all set of 10

fingerprints in the world to be divided into 1024 groups.

Table 4.2 Frequency of fingerprints Loops WhorlsArchesUlnar radial plain other plain tented60% 5% 20% 10% 4% 1% loops = 65% whorl=30% arches =5%

Kendall/Hunt Publishing Company 79

Primary Classification

The Henry—FBI ClassificationEach finger is given a point value

right left

Kendall/Hunt Publishing Company 80

Primary Classification

Assign the number of points for each finger that has a whorl and substitute into the equation:

right right left left left index ring thumb middle little + 1

right right right left left thumb middle little index ring +1

That number is your primary classification number

=

Thursday 12/4/14

• AIM: how can we identify unknown fingerprints?

• DO NOW: Explain how you would connect a fingerprint found at a crime scene to a suspect

• HW: Handout question 1-12 due TOMORROW

DO NOW ANSWER

• Compare friction ridges or minutiae patterns• 8-12 similarities match the suspect to the

unknown

Friday 12/5/14

• AIM: How are fingerprints used to connect a suspect to a crime?

• DO NOW: Take out last nights homework and pass it up

• 2- Worksheet identify fingerprint patterns and minutiae

• 1- core: the central part of a pattern that defines the pattern

• 2- delta: a triangular shaped ridge pattern that helps define the pattern

Characteristics of a loop• 1 delta• Ridge enters and exits on same side• Type of loop is determined by the direction of

the opening• Radial: thumb Ulnar: pinky

The number of deltas

Types of whorls

• Plain, central pocket, double loop, accidental

Monday 12/8/14

• AIM: How can we analyze fingerprint minutiae patterns?

• DO NOW: Handout compare the fingerprints• HOMEWORK: Handout

Right hand

Prove that these two fingerprints are identical

How do you individualize a fingerprint?

Comparison

• Individuality is determined by its RIDGE CHARACTERISITICS or MINUTIAE.

• Prints taken from the scene of a crime must show areas of commonality with a known set of prints to get a conviction

• Core: center where pattern begins• There are no legal requirements

in the United States on the number of points

• Generally, criminal courts will accept 8 to 12 points of similarity.

Fingerprinting in the US

• NY was the 1st state to use fingerprints – 1901

• Became the official system of criminal identification in the U.S. in 1924 at the formation of the F.B.I.

1999 – US vs. Mitchell

• Challenged the individuality of fingerprints• Court ruled:

– Human friction ridges are unique & permanent

Modern Fingerprint Analysis

Computer system stores patterns and minutiae of prints

AFIS: automated fingerprint identification system

Fingerprints

Automated Fingerprint Identification System (AFIS) - YouTube

105

What is a Fingerprint?

• Skin has an outer layer (epidermis) which has ridges projecting inward, and an inner layer (dermis) which has projections pressing into the spaces between ridges

• A fingerprint is a pattern made by the friction ridges, which is left behind due to sweat and oil that sticks to them.

• Fingerprints form during the fetal stage of development.

WHAT IS A FINGERPRINT?WHAT IS A FINGERPRINT?

A fingerprint is a pattern comprised of ridges and valleys.

A Ridge – is a high.

A Valley – is a depression or low.

A fingerprint is a pattern comprised of ridges and valleys.

A Ridge – is a high.

A Valley – is a depression or low.

Friction ridges are also found on our palms, feet and toes.Friction ridges are also found on our palms, feet and toes.

Why do clones have different fingerprints?

ValleyRidge

Anatomy of fingerprints

• Finger touches a surface–Perspiration–Oils from hairy portions of the body

–Transferred onto surface• Leaves fingerprint

109

• AIM: How are latent fingerprints lifted from a crime scene?

There are 3 types of fingerprints

1. Visible – left by dirt, grease, blood, etc. Does not need processing

There are 3 types of fingerprints

2. Impression – indentation in soft material (butter, putty, tar, etc.)

Does not need processing

There are 3 types of fingerprints

3. Latent – requires processing to make visible and suitable for analysis

What are the invisible components?

Multiple sweat glands secrete onto fingers, palms, etc.

Sweat contains:

Inorganic ions (Na+, Cl -) Proteins, amino acids

Lipids Other

Fingerprinting

Recording or Making Prints rolling inked prints primary identification number

Lifting Prints Black, white and fluorescent powder Chemicals—ninhydrin, iodine, silver nitrate, cyanoacrylate

Other Types of Prints Palm, lip, teeth, eye, ear, voice, shoe and footprints

https://www.youtube.com/watch?v=w7wUuRiMCuM

117

Lifting Latent Prints

Developing a print requires chemicals that react with secretions that cause the print to stand out against its background.

Physical development: uses powders to dustChemical development: uses chemicals to fumePowders--adhere to both water and fatty deposits. Choose a

color to contrast the background.

Physical Development: Dusting

Apply powder to latent print or area.

Powder adheres to print.

Brush and Powder

Physical Development: Dusting

Apply powder to latent print or area.

Powder adheres to print.

Magnetic Brush

and Powder

Chemical Development of latent prints

Iodine--fumes react with oils and fats to produce a temporary yellow brown reaction.

Ninhydrin--reacts with amino acids to produce a purple reaction.

Silver nitrate--react with chlorides to form silver chloride, a material which turns gray when exposed

to light. Cyanoacrylate--”super glue” fumes react with water and

other fingerprint constituents to form a hard, whitish deposit.

Thursday 12/4/14

• AIM: How are latent fingerprints lifted from a crime scene?

• DO NOW: Handout: Identify the minutiae patterns.

• HOMEWORK: Text page 100-101 questions 11,12,14

Chemical Development:

1. Silver Nitrate

No longer used (messy, not sensitive) Silver reacts with Cl - ions in print

Chemical Development:

2. Iodine Fuming Iodine sublimes

(solid → gas) Iodine reacts with lipid

components; becomes trapped in the print.

Fuming wand or chamber

Dirty Brown Color

Fingerprints > Analysis

124

Iodine Fingerprint

Chemical Development:

3. Ninhydrin Reacts with amino acids; purple color Painted or sprayed on area Heated to react

126

Ninhydrin Fingerprint

Chemical Development:

4. Super glue fuming Fumes with heat or base (NaOH) Fumed in cabinets Off-white print

128

Cyanoacrylate Fingerprints

Chemical Development:

Ninhydrin and super glue prints can be further processed:

Dusted Chemically treated to

fluoresce (using laser or alternative light)

Friday 12/5/14

• AIM: How do we reinforce fingerprinting techniques

• DO NOW: 2 minute mystery