Fingerprints. Structure (basics) Finger Pads –fleshy part of finger tip used for touching and gripping Grooves – narrow valleys between ridges Friction.

Fingerprints

Structure (basics)• Finger Pads –fleshy part of

finger tip used for touching and gripping

• Grooves – narrow valleys between ridges

• Friction Ridges – “hills” or fine lines that create a fingerprint and give fingers traction

*Ridges evolved because they allow humans to grip things – like tools!

Fingerprint History• Early potters identify works with an impresses

fingerprint

• 1000 BC –Chinese sign legal documents with fingerprints

• 1685 – Marcello Malpighi, an Italian physician, recognizes patterns of fingerprints as “varying ridges and patterns”

• 1823 – Johannes Purkinje establishes 9 basic fingerprint patterns and a system to classify them

• 1858 – Sir William Herschel requires natives in Bengal, India to sign contracts with a handprint to prevent fraud – suggests prints do not change

• 1880 – Henry Faulds (physician and surgeon) discovers dusting latent (invisible) prints with powder exposes them

• 1892 – Francis Galton offers evidence that no two prints are the same; Juan Vucetich (Argentinian police officer) devises a fingerprint classification system still used widely in South America

• 1897 – Herman Welcer finds his own prints are unchanged from 41 years earlier.

• 1899 –Sir Edward Henry devises a classification system based on five types of prints. This system is still used today in the the UK and United States.

• 1910 – Thomas Jennings becomes the first person in the United States to be convicted of a crime based on fingerprint evidence.

Fingerprinting Outline

Look through the events in history that you have just taken notes on. Outline / list the key discoveries that make fingerprints a useful tool for identification of an individual.

Principles of Fingerprinting

1. A fingerprint is individual and is not shared by any two people.

2. A fingerprint remains unchanged throughout life.

3. Fingerprints exhibit general patterns that provide a basis for classification.

Anthropometry

• A system of body measurements used to identify an individual

• Known as bertillonage – named for Alphonse Bertillon (1883)

Bertillonage measurements:• Height• Stretch: length of body from left shoulder to right middle finger

when arm is raised• Bust: Length of torso from head to seat, taken when seated• Length of head: Crown to forehead• Width of head: Temple to temple• Length of right ear• Length of left foot• Length of left middle finger• Length of left cubit: Elbow to tip of

middle finger• Width of cheeks

Will West Case

In May 1903, a clerk at Leavenworth Penitentary in Kansas thought Will West looked familiar. He said he had not been to prison before, but had the exact measurements of another inmate, William West. They said they were not brothers (it turns out they were identical twins).

Fingerprints helped distinguish between the two men, leading prisons to dump anthropometry and go to a fingerprint-based system for identifying prisoners.

Can you change your fingerprints?

Yes. With some effort. • If someone burns or shaves off pads of fingers,

the prints disappear for a while, but do grow back.

• More severe damage may leave a permanent scar. However, scars are unique as well.

John Dillinger – Public Enemy Number 1

• John Dillinger video clip• In an effort to evade police, Dillinger underwent

facial surgery and tried to remove his fingerprints with acid. Despite his efforts, his prints still matched with those on file.