Forensic Science Lesson 06: Fingerprints 1

Fingerprints

Lesson Objectives

• Describe the history of Fingerprint Evidence

• Describe what Fingerprints are and how they are made

• Describe the three main types of Fingerprints

Fingerprints as a Forensic Tool

• Fingerprints are the oldest of all forensic Evidence

  • Used to identify artists in Ancient Babylon

  • Used as a signature in Ancient China

• Dactyloscopy: The Study of Fingerprints

• 1684: Dr. Nehemiah studied fingerprints under a microscope for the first time

  • 1788: Johann Christoph Andreas Mayer continues his studies

    • Finds that no two fingerprints are the same

Alphonse Bertillon

• 1879: Alphonse Bertillon

  • Clerk in Paris Police

  • Created the first system of identifying someone by fingerprints called the Bertillonage

    • Was adopted due to being more humane than other means of forced Identification

  • Solved the first murder using fingerprints in 1902

Fingerprints vs Antrhopometry

• Anthropometry: The study of Human body measurements

• In 1881-Bertillion Initially proposed using this as a form of Identification for prisoners

  • Recorded measurements included:

    • Body Height

    • Outstretched arm length

    • Length/Width of ears

    • Length/width of feet

Why Don't we Still Use Antrhopometry

• 1903: Will West arrives at Leavenworth Prison

  • Measurements were taken and compared to others in the record

  • A second man William West was found to be already in prison with almost identical measurements

  • Fingerprints were taken of the two men and were found to be different

• Over time, fingerprints were found to be more reliable overall

The Henry System

• 1888: Sir Francis Galton and Sir E. R. Henry refine Bertillon's system into the Henry System

  • still used today in the US and Europe

    • Ten Card: a form used to record and preserve a person’s fingerprints

What are Fingerprints?

• All people have ridges on their fingers, palms, toes, and feet

  • Not necessarily the same for each digit, but all unique

• Fingerprint: an impression left on any surface that consists of patterns made by the ridges on a finger

  • Consists of sweat, skin oil, salt, and dirt

  • Are unique to each person and consistent throughout their lifetimes

Multiple Choice

The first system of identifying a person based on Fingerprints was called the

• Mayer System

• Galton-Henry records

• Bertillonage

• A ten-Card

Drag and Drop

​

Placeholder

is the study of measurements of the human body. It was used to identify individuals in the past, but has since been replaced with​ ​

Placeholder

, which is the study of human fingerprints.

Drag these tiles and drop them in the correct blank above

Anthropometry

Dactoloscopy

Podiatry

Entomology

Oncology

Meteorology

Multiple Choice

What is the name for the form used to record and preserve a person's fingerprints?

• Handprint card
• Print Record

• Ten card

• Finger File

• Print Measurement system

Anatomy of Fingerprints

• The skin has three layers:

  • Epidermis

    • Divided into smaller layers

  • Dermis

  • Hypodermis

• Fingerprints form on the epidermis around the 10th week of pregnancy

  • One layer of the epidermis grows faster than the others, causing the skin to fold up

  • Once the folds form, the skin continues to regenerate in that shape

  • Because Each person grows at their own rate in their own unique conditions, the rate of growth varies from person to person

    • Every individual has their own unique set of fingerprints

Do all animals have fingerprints?

• Most animals do not have fingerprints, but different sorts of patterns

• Fingerprints are an evolutionary adaptation for grasping objects, so most species do not have them

• All Primates have Fingerprints

  • Humans, Monkeys, Chimpanzees, and Apes

• Koalas have fingerprints that are so similar to humans, they can be mistaken for human fingerprints

Multiple Choice

Fingerprints form on which layer of skin

• Epidermis

• Dermis

• Hypodermis

• All Layers of Skin

Reorder

Order the layers of the skin from the outermost layer to the innermost Layer

• Epidermis

• Dermis

• Hypodermis

1

2

3

• 1
• 2
• 3

Multiple Choice

Which of the following is not a part of a fingerprint?

• Hair

• Dirt

• Sweat

• Oil

Characteristics of Fingerprints

• Fingerprints are divided into three broad categories, based on the shapes seen in them

  • Loops

  • Whorls

  • Arches

Arches

• About 5% of the population

• Ridges go across the finger, with a bump in the middle

• When the arch has a high bump, it is called a Tented Arch

Loop & Whorl Similarities

• Both Loops and Whorls consist of Two parts

  • Core: a center of a loop or whorl

  • Deltas: a triangular ridge pattern with ridges that go in different directions above and below a triangle

Loops

• About 65% of the population

• Enter and exit from the same side of the fingerprint

• Have one Delta

• Two types

  • Radial: Loop opens toward the thumb/radius bone

  • Ulnar: Loop opens away from the thumb/toward the Ulna bone

    • More common than Radial loops

• You can only distinguish between the two types if you know which hand the prints are from

Whorls

• About 30% of the population

• form a sort of bullseye that spirals out from the center

• Have at least two deltas

Fingerprint Patterns

• The three shapes of a fingerprint can help to narrow down a suspect pool, but not definitively Identify a person

  • Each person has Unique Ridge Characteristics that can help identify an individual

• Minutiae: the combination of details in the shapes and positions of ridges in fingerprints that make each unique;

  • also called ridge characteristics

  • 150 different types

Poll

Look at your hands. What type of Fingerprint do you have?

• Arch

• Loop

• Whorl

Multiple Choice

What is the least common Fingerprint type

• Arch

• Loop

• Whorl

• All Fingerprints appear at the same frequency

Multiple Choice

True or False: Humans are the only creature on Earth with fingerprints

• True

• False

Match

Match the following Fingerprint to its type

Arch

Whorl

Loop

• Arch

• Whorl

• Loop