Notes Ch. 14 Fingerprints

I. History of Fingerprints Police have always looked for a foolproof method of human identification. 1 st system: Bertillon 1883 called anthropometry

A. Early Use of Fingerprints 1.Chinese: ~1000 B.C. used F.P. to sign legal documents : Fauld and Herschel suggested that fingerprints are useful for ID criminals

B. Early Classification of Fingerprints 1.Galton, in 1892, published Finger Prints a.Demonstrated no 2 F.P. are identical b.Showed individuals F.P. remain unchanged in life c.Proposed 3 F.P. categories 1. Loops (~60%) 2. Whorls (~30-35%) 3. Arches (~5-10%)

2. Development of Classification System a. Dr. Juan Vucetich-Argentina 1891 (still used in most Spanish speaking countries today) b. Sir Edward Henry-England 1897 (used in U.S., England, etc.)

C. Adoption of Fingerprints New York City adopted F.P Prison “Twins” -2 criminals looked and measured identically -fingerprints were very different World’s Fair: Police trained by Scotland Yard

II. Fundamental Principles of F.P. A.First Principle: -A F.P. is an individual characteristic -No two fingers have yet been found to possess identical prints *Currently 60 million F.P. in FBI database

1.I.D. of fingerprints based on Ridge Characteristics (a.k.a. minutaie) 2.Ridge Characteristics A. bifurcation B. ridge ending C. ridge island D. enclosure E. short ridge F. bridge G. Crossover H. Spur (hook)

Let’s practice! Take out a pen (blue or black ink) and clear everything else off your desk. Balloon prints

B. Second Principle 1. A fingerprint remains unchanged during an individuals lifetime a. Fingerprints develop at 3 months gestation. b. Many criminals have tried to alter/eliminate them.

2. Shape of dermal papillae determines form and pattern of ridges Papillae are cells that separate epidermis from dermis.

C. Third Principle Fingerprints have general ridge patterns that permit them to be systematically classified 1.General patterns A.loops (~60-65% of population) 1. ulnar loop2. radial loop B. whorls (~30-35%) 1. plain whorl 2. central pocket whorl 3. accidental whorl 4. double loop whorl C. arches (~5%) 1. plain arch2. tented arch

III. Classification of Fingerprints

A. Fingerprint Vocab 1. Core: center of the fingerprint 2. Delta: triangular area

B. Specific Types of Fingerprints Two Types of ARCHES

Arch-all lines enter and exit from opposite sides of finger 2. Tented Arch- drastic spike 1. Plain Arch- rolling hill

2 Types of Loops Must know which hand you are looking at to determine!! Loop-only one delta; at least one ridge line enters and exits same side of print

4 Types of Whorls 1. Plain Whorl- line between deltas intersects circles 2. Central Pocket Loop Whorl- line btwn deltas does not intersect full circles; whorl-2 deltas; at least one ridge line does not exit finger

Practice Plain whorl or central pocket loop whorl? ANS: Central pocket loop whorl

Practice Plain whorl or central pocket loop whorl? ANS: Plain whorl

More Whorls 3. Double loop whorl: looks like yin yang 4. Accidental whorl- characterized by 3 deltas; frowny face

Accidental Whorls: 2 or more types of prints More Examples

Practice Double loop whorl or accidental whorl? ANS: double loop whorl

Practice Double loop whorl or accidental whorl? ANS: accidental whorl

Let’s practice! Please take your Unit 2 classwork paper. Date: 9/22/14 Title: WS: Classification of FP #2

C. Fingerprint Classification Code 1. Every print is given a code after it enters the F.P. database 2. 1 st classification step called the primary classification 3. Code is based on presence or absence of whorl 4. Approximately 25% of the population falls into the 1/1 category (they do not have any whorls)

Fraction = R.Index R. Ring L. Thumb L. Middle L. Little +1 R.Thumb R.Mid R. Little L. Index L. Ring +1 (16) (8) (4) (2) (1)

Example #1: Suspect F.P. FingerLeftRight ThumbArchLoop IndexLoop MiddleWhorlArch RingLoop LittleArchWhorl = 3535

Example #2 FingerLeftRight ThumbArchWhorl IndexLoop MiddleLoopArch RingLoopWhorl LittleArch Suspect F.P = 9 17 **Do not reduce fraction: 2/4 stays as 2/4

Practice Find your own classification code. Determine your partner’s classification code. Compare your answers. Take out Unit 2 Classwork paper. Date: 9/23/14 Title: FP Code Practice

D. AFIS AFIS : Automated Fingerprint Identification System FBI has largest Some cities, counties, states have their own that may or may not link to FBI Converts image of fingerprint into digital scan with reference points to ridge endings and bifurcations

III. 3 Types of Crime Scene Prints 1.Visible-can be seen by naked eye Ex: prints left in blood, paint, dust, grease, ink 2.Plastic-occurs when ridge impressions are left in soft material Ex: prints left in wax, play-doh, soap, puddy 3.Latent (Invisible)-not seen by naked eye; caused by a transfer of oils onto surface

IV. Methods for Developing Latent Prints Super Glue Fuming-nonporous materials Dusting-nonporous materials Iodine Fuming-porous materials Ninhydrin-porous materials Physical Developer-porous materials

V. Locating Fingerprints Visible and plastic easy to see Latent: RUVIS (reflected ultraviolet imaging system) – aims UV light at a surface suspected of having prints – Light is converted into visible light

VI. Proper Collection of F.P. Step 1: Location documented, object photographed Step 2: – Small Object: taken back to lab, F.P. developed there – Large Object: F.P. developed and lifted at crime scene