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History Alphonse Bertillion French police expert First systematic attempt at personal identification was Bertillion system Relied on a detailed description of the subject Combined with full length and profile photographs System of precise body measurements called anthropometry FINGERPRINTS

History Francis Galton 1892 Classic textbook finger prints At Galton��s insistence British government adopted fingerprinting Supplement to the bertillion system. Next step Creation of classification systems Capable of filing many thousands of prints Logical and searchable sequence. FINGERPRINTS

History Dr Juan Vucetich Devised a classification system Still used in most spanish-speaking countries Sir Edward Henry: system used in most English-speaking countries. Will West and William West case 1903 Bertillion system could not distinguish between men Fingerprinting that clearly distinguished them FINGERPRINTS

History Fingerprinting used by the New York city civil service commission in 1901 Training of American police by Scotland yard representatives at the 1904 world��s fair FINGERPRINTS

Fingerprint Principles Reproduction of friction skin ridges Palm side of the fingers & thumbs FINGERPRINTS

Fingerprint Principles Individual characteristic Because no two fingers with with identical ridge characteristics Remains unchanged during an individual��s lifetime General ridge patterns that permit systematic classification FINGERPRINTS

Principle One Individual Characteristic No Fingers Identical

Principle One Mathematical probability for existence of two identical fingerprint patterns in the world��s population = almost zero Millions upon millions of individuals who have had their prints classified No two fingerprints have been found to be identical FINGERPRINTS

Figure 14�C1??Fingerprint ridge characteristics. Courtesy Sirchie Finger Print Laboratories, Inc., Youngsville, N.C., www.sirchie.com.

Principle One Individuality of fingerprint not determined by its general shape or pattern Careful study of its ridge characteristics, known as minutiae. Identity, number, and relative location Individuality to a fingerprint. As many as 150 minutiae on the average finger FINGERPRINTS

Principle One Three year study �� No valid basis exists for requiring a predetermined minimum number of friction ridge characters which must be present in two impressions in order to establish positive identification�� Judicial proceeding Expert must demonstrate a point-by-point comparison To prove the identity of an individual FINGERPRINTS

Fingerprint Comparison Figure 14�C2??A fingerprint exhibit illustrating the matching ridge characteristics between the crime-scene print and an inked impression of one of the suspect��s fingers. Courtesy New Jersey State Police.

Principal Two Remains Unchanged During Lifetime

Principal Two 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

Principal Two Dermal papillae develop in the human fetus Ridge patterns will remain unchanged throughout life Enlarge during growth Fingerprint remains unchanged during lifetime

Principle Two Skin ridge is populated with pores leading to sweat glands Perspiration is deposited on the skin FINGERPRINTS

Principle Two Finger touches a surface Perspiration Oils from hairy portions of the body Transferred onto surface Leaves fingerprint FINGERPRINTS

Principle Three Ridge Patterns Permit Systematic Classification

Principle Three All fingerprints divided into three classes Loops Arches whorls L.A.W. FINGERPRINTS

Principle Three - Loops A loop must have one or more ridges entering from one side of the print, recurving, and exiting from the same side. If the loop opens toward the little finger, it is called an ulnar loop. If the loop opens toward the thumb, it is called a radial loop.

Principle Three - Loops Figure 14�C5??Loop pattern.

Principle Three - Loops Must have one delta Ridge point at or directly in front of the point where two ridge lines (type lines) diverge FINGERPRINTS

Principle Three- Whorls Divided into four groups Plain Central pocket loop Double loop Accidental All have type lines and minimum of two deltas FINGERPRINTS

Whorls Plain whorl and central pocket loop have at least one ridge that makes a complete circuit Double loop: two loops combined into one fingerprint Accidental Two or more patterns Or pattern not covered by the other categories FINGERPRINTS

Plain Whorls More than 1 valid delta If you look at image A? you should be able to identify the two delta's. If not then look at image B and you will see that they are displayed in the red boxes. Whorl: one or more ridges which make complete circuit Two delta's Between which an imaginary line is drawn At least one recurving ridge within the inner pattern area cut or touched.?

Whorls Inner area of the pattern forms circle or oval Specific ridges that are making or trying to make the circle Imaginary line between the two delta's (the red line in image) No lines that form the circle are intersected

Principle Three - Arches Least common of general patterns Plain arches Tented arches No lines that form the circle are intersected FINGERPRINTS

Plain Arches Ridges entering from one side of the print Rising and falling Exiting on the opposite side Like a wave

Tented Arches Sharp upthrust or spike The ridges meet at an angle that is less than 90 degrees Arches do not have type lines, deltas, or cores FINGERPRINTS

Primary Classification Based on knowledge of fingerprint pattern classes Fingers are paired up One finger in the numerator of a fraction Other in the denominator Presence or absence of the whorl pattern Basis for the determination of the primary classification FINGERPRINTS

Primary Classification Whorl pattern Any finger of the first pair value = 16 On the second pair value = 8 On the third pair value = 4 On the second pair value = 2 On the last pair value = 1 Any finger having a loop or arch value = 0 FINGERPRINTS

Primary Classification Values for all 10 fingers totaled 1 is added to both the numerator and denominator Fraction obtained is primary classification. FINGERPRINTS

Primary Classification 25 percent of the population 1/1 category All fingers loops or arches Cannot in itself unequivocally identify an individual Provides the fingerprint examiner with a number of candidates

AFIS Computer to scans, digitally encodes fingerprints Can be high-speed computer processed FINGERPRINTS

AFIS AFIS aids in classifying and retrieving fingerprints Converts image of a fingerprint into digital minutiae Contain data showing ridges at their points of termination (ridge endings) and their branching into two ridges (bifurcations). Thousands of comparisons per second Produces a list of file prints to be examined by a trained fingerprint expert FINGERPRINTS

Latent Prints Invisible fingerprints Finger touches a surface Body perspiration and/or oils present Transferred to that surface Leaves impression Invisible to the eye FINGERPRINTS

Visible Prints Fingers touch a surface after contact with a colored material such as blood, paint, grease, or ink Plastic prints: left on a soft material, such as putty, wax, soap, or dust Little problem to the investigator Usually distinct and visible to the eye. FINGERPRINTS

Detecting Prints Hard nonabsorbent surfaces Glass, mirror, tile, painted wood Developed by the application of a powder Porous surfaces Papers, cardboard, and cloth Require treatment with a chemical FINGERPRINTS

Ninhydrin Reacts chemically with trace amounts of amino acids Produces a purple-blue color Messy and stains skin badly

Physical Developer Silver nitrate-based reagent Used when other chemical methods are ineffective Silver nitrate solution stain skin

Super Glue ? Nonporous surfaces Metals, electrical tape, leather, plastic bags Fumes from the glue adhere to the print Produce white latent print 98 to 99 percent cyanoacrylate ester Super Glue fuming Fuming chamber (for up to six hours) Handheld wand that heats a small cartridge containing cyanoacrylate FINGERPRINTS

Reflected UV Imaging System RUlVIS No chemicals or powder Locate With light source investigator develops the print in the most appropriate fashion FINGERPRINTS

Figure 14�C17??Schematic depicting latent-print detection with the aid of a laser. A fingerprint examiner, wearing safety goggles containing optical filters, examines the specimen being exposed to the laser light. The filter absorbs the laser light and permits the wavelengths at which latent-print residues fluoresce to pass through to the eyes of the wearer. Courtesy Federal Bureau of Investigation, Washington, D.C.

Powders Powders, available in a variety of colors, can be applied with a brush or magnetic wand, and adhere to perspiration and/or body oils of the print.

Iodine Fuming Molecular iodine solid at room temperature Heat iodine crystals Iodine vapors Combine with latent prints to make them visible Iodine prints are not permanent Will fade Must photograph the prints immediately

Fluorescence High sensitivity New chemical techniques used to visualize latent fingerprints Fingerprints treated with chemicals Induce fluorescence when exposed to lasers High-intensity light sources (��alternate light sources��) Quartz halogen, xenon arc, or indium arc light sources. FINGERPRINTS

Preservation of Prints Visualized latent print Permanently preserved Future comparison Possible use as court evidence Photograph must be taken Before any attempts at preservation

Transporting Prints small object: preserve in its entirety. large immovable objects developed with a powder �� lift�� with a broad adhesive tape. tape placed on properly labeled card good background contrast with the powder FINGERPRINTS

Digital Imaging Picture converted into digital computer file Help of digital imaging software Enhanced for the most accurate and comprehensive analysis Compare function Two images side by side Allows the examiner to chart the common features on both images simultaneously FINGERPRINTS

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