Bertillonage Alphonse Bertillon in 1879 Based on 243 body measurements Surprisingly accurate but proved too cumbersome to use Replaced by new technique called fingerprinting

Big Men in Fingerprinting History Dr. Henry Faulds – Scottish physician in Tokyo published a letter in Nature in 1880 concerning fingerprints Sir William Herschel – chief Administrative Officer of Bengal used thumb prints to identify illiterate prisoners

Big Men in Fingerprinting History Sir Francis Galton – performed the first serious study of fingerprinting and published Finger Print in 1892 Sir Edward Henry – developed classification system based on patterns of ridges. Still used in most English speaking countries today.

How are fingerprints formed? Only found on hairless parts of body Formed by papillary ridges by the fourth month of pregnancy

How are fingerprints formed? Skin has two layers – dermis & epidermis Epidermis is constantly being worn away

How are fingerprints formed? Sweat glands secrete sweat to skin surface Sweat necessary to form latent prints

Types of Fingerprints Latent – the most frequently found –invisible to the eye –formed by sweat, oil on surfaces of finger ridges –must be treated with chemicals, powders, etc. to be visible

Types of Fingerprints Visible – easily seen by the unaided eye –most common when fingers are blood stained –can also be made by ink or other similar medium staining fingers of person leaving print –rarely found at crime scenes since perpetrators would attempt to wipe away easily seen evidence of this type

Types of Fingerprints Plastic – a.k.a. molded print –made by impression of fingerprint in soft material –soft material might be drying paint, putty, soap and cheese (most often the bane of dairy thieves the world over!)

Fingerprint Patterns & Minutiae Arch Tented Arch Loop Double loop Pocket loop Whorl Accidental

Fingerprint Patterns Describes the shapes that are produced by the black or colored portions of the fingerprint, NOT the white or uncolored portions The black portions are called ridges

Fingerprint Patterns Ridge ending – a ridge that ends abruptly

Fingerprint Patterns Bifurcation – a single ridge that divides into two ridges.

Fingerprint Patterns Lake or enclosure – a single ridge that bifurcates and reunites a short time after to form a single ridge

Fingerprint Patterns Short ridge, island or independent ridge – a ridge that starts, travels a short distance and then ends

Fingerprint Patterns Dot – an independent ridge with approximately equal length and width

Fingerprint Patterns Spur – a bifurcation with a short ridge branching off a longer ridge

Fingerprint Patterns Crossover or bridge – a short ridge that runs between two parallel ridges

Fingerprint Principles Immutable – the patterns of ridges do not change over the course of a person’s life. The patterns begin to form on the skin surface during the third month of pregnancy. Unique – the patterns of ridges are specific to the person. Even identical twins have unique fingerprints.

Fingerprint Patterns - Arches Made up of ridges lying one above the other in a general arching formation Least common of the general patterns of fingerprints. Two types of arches: plain, like shown here

Fingerprint Patterns - Arches Tented arch Sharp upthrust of sides of arch results in an angle that is less than 90°

Fingerprint Patterns - Loops Consists of one or more free-recurving ridges and one delta Radial loop – loop comes from thumb side of hand Ulnar loop – loop comes from pinkie finger side of hand NOTE: Perpetrators rarely leave Post-it notes telling you which hand they used during a crime!

Fingerprint Patterns - Whorls Consists of one or more free-recurving ridges and two deltas Divided into four distinct groups. This is a plain whorl

Fingerprint Patterns - Whorls Double loop pattern Recurving ridges present two loop formations that are separate and apart Flows for deltas originate from the same side of the pattern.

Fingerprint Patterns - Whorls Central pocket loop consists of one or more free recurving ridges and two points of delta “Lollipop” effect with one delta and its ridge lines

Fingerprint Patterns - Whorls Central pocket loop consists of one or more free recurving ridges and two points of delta “Lollipop” effect with one delta and its ridge lines

Fingerprint Patterns - Whorls Accidental pattern – will contain two points of delta. One delta will be related to a recurve and the other will be related to an upthrust.

Points of Identification The same minutiae are present The minutiae flow in the same direction The minutiae occupy the same relative positions to each other

Henry Classification R. Index (16) R. Ring (8) L. Thumb (4) L. Middle (2) L. Little (1) R. Thumb (16) R. Middle (8) R. Little (4) L. Index (2) L. Ring (1) Approximately 25% of the population falls into the 1/1 category Classification system based on the presence of whorl pattern in the fingerprint.