Ch 14 Fingerprints I History of Fingerprints

Ch. 14 Fingerprints

I. History of Fingerprints • Police have always looked for a foolproof method of human ID. • 1 st system: Bertillon 1883 called anthropometry. French police expert

A. Early Use of Fingerprints 1. Chinese : ~1000 B. C. used F. P. to sign legal documents in clay Scotland Yard said “thanks, but no thanks!” 2. 1880: Faulds and Herschel suggested that fingerprints are useful for ID criminals

B. Early Class. of F. P. ’s *1892: Galton published Finger Prints 1. Demonstrated no 2 F. P. are identical 2. Showed individual’s F. P. remain unchanged in life 3. Proposed 3 F. P. categories 1. Loops (~60%) 2. Whorls (~30 -35%) 3. Arches (~5 -10%)

Loop Enters and exits same side of finger at least once, 1 delta Whorl At least 2 deltas Arch All lines enter and exit from different sides

C. Two Classification Systems 1. 1891: Dr. Juan Vucetich 2. 1897: Sir Edward Henry (used in U. S. , England, etc. )

D. Adoption of Fingerprints 1. 1901: New York City adopted F. P. 2. 1903: Prison “Twins” – Will West’s -2 criminals with same name looked & measured identically ‘s were very different 3. 1904: World’s Fair-Police trained by Scotland Yard

II. Classification of Fingerprints

A. Fingerprint Vocab 1. Ridge Characteristics (“minutiae”): Ridge endings, bifurcations, enclosures, & other ridge details 2. Core: center of the fingerprint 3. Delta: triangular area; splits into Y

B. Specific Types of Fingerprints • Two Types of ARCHES 1. Plain Arch: rolling hill 2. Tented Arch: drastic spike

• 2 Types of Loops 1. Ulnar Loop Opens towards pinky 2. Radial Loop Opens towards thumb *Must know which hand you are looking at to determine!!

• 4 Types of Whorls 1. Plain Whorl: line between deltas intersects circles 2. Central Pocket Loop Whorl: line btw. deltas does not intersect full circles

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

More Examples Accidental Whorls: 2 or more types of prints

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

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

Radial vs. Ulnar Loops Review

Reclassification of your own F. P. ’s

III. F. P. Classification Code 1. Every print is given a code in the FBI database – Series of letters and numbers 2. Primary Classification is only 1 st step 3. Code is based on presence or absence of whorl 4. ~ 25% of the pop. falls into the 1/1 category – only arches or loops • Score of “ 0” – no whorls • Positive number scores

Primary Classification Coding (Fraction obtained) R. Index R. Thumb (16) + R. Ring R. Mid. (8) L. Thumb R. Little (4) L. Mid. L. Index (2) L. Little L. Ring 1 1 (1)

Practice Take out Classwork paper. Date: 9/19/16 Title: FP Code Practice

Code Practice #1: • Suspect F. P. Finger Left Right Thumb Arch Loop Index Loop Middle Whorl Arch Ring Loop Little Arch Whorl 0 0 0 _ _ _ 0 0 4 2 0 _ _ 0 0 3 1 _= _ 1 5

#2 • Suspect F. P. Finger Left Right Thumb Arch Whorl Index Loop Middle Loop Arch Ring Loop Whorl Little Arch 0 8 0 _ _ _ 16 0 0 _ _ 0 0 9 1 _= _ 1 17 **Do not reduce fraction: 2/4 stays as 2/4

#3 Finger Left Right Arch 0 Whorl 16 Index Whorl 2 Whorl 16 Middle Whorl 2 Arch 0 Ring Loop 0 Whorl 8 Little Whorl 1 Arch 0 Thumb = 28 19 1 1

Find your own Code Finger Left Right Thumb ? ? Index ? ? Middle ? ? Ring ? ? Little ? ? Cheat Sheet Finger Left Right Thumb 4 2 16 Middle 2 8 Ring 1 8 Little 1 4 2 2 16 16 Index 1 1 8 8 4 4 16

IV. Fundamental Principles of F. P. A. First Principle: 1. A F. P. is an individual characteristic 2. No fingers with identical prints … yet *Currently 450 million F. P. in FBI database 3. Identification of F. P based on Ridge Characteristics (a. k. a. minutiae)

Ridge Characteristics a. Ridge ending b. bifurcation (fork) e. Bridge f. Spur (hook) c. short ridge d. ridge island (dot) g. Enclosure (eye) h. Crossover

Ridge Characteristics Identification - Review

Fundamental Principles of Fingerprints 2 nd and 3 rd Principles

B. Second Principle 1. A fingerprint remains unchanged during an individuals lifetime FUN FACTS a. Fingerprints develop at 3 months gestation. b. Many criminals have tried to alter/eliminate them. - John Dillinger c. Three genetic conditions can prevent fingerprints from forming

2. Shape of dermal papillae determines form and pattern of ridges Why Do We Have Fingerprints? *Papillae are cells that separate epidermis from dermis.

C. Third Principle *Fingerprints have general ridge patterns that permit them to be systematically classified 1. Three General patterns (loops, whorls, arches) A. loops (~60 -65% of population) B. whorls (~30 -35%) C. arches (~5%) 2. Individuality of a F. P. is determined not by its general shape, but by a careful study of its ridge characteristics.

Identify your own minutiae • Take out a pen (blue or black ink) and clear everything else off your desk. • Directions: • Identify 12 different Ridge Characteristics • Must have at least five diff. R. C. ’s out of your 12! • Must have a label and an “→”

AFIS, F. P. Types, Locating, & Developing

D. AFIS 1. Automated F. P. ID System 2. Converts image of F. P. into digital scan 3. Reference points – ridge endings & bifurcations

AFIS (cont. ) 4. FBI has largest database in world – Some cities, counties, states have their own that may or may not link to FBI 2 • Software config. 5. Positive match is approx. 8 -16 points, but min. zero req. for court (USA)

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

VI. Locating Fingerprints • Visible & plastic easy to see • Latent: RUVIS (Reflected UV Imaging Sys. ) – UV light aimed at surface suspected of having prints – UV light is converted into visible light

VII. Methods for Devel. Latent Prints A. Nonporous Materials (glass, metal, plastic) • Super Glue Fuming • Dusting B. Porous Materials (wood, paper) • Iodine Fuming • Ninhydrin • Physical Developer

C. Dusting Powders • Stick to the oils in the fingerprint (physical) • Come in variety of colors/compositions • most common: black, gray, and white

D. Super Glue Fuming • cyanoacrylate in glue reacts with proteins and fatty acids in F. P. (chemical) • Creates white print • Must be further developed with powder heated fuming cabinet

Developing Latent Prints – Porous Materials

E. Iodine Fuming • Iodine sublimes at room temp. ( solid gas ) • Gaseous iodine sticks to oils in F. P. (physical) • Oldest method • Temporary, fades quickly • Can be fixed by spraying with starch solution • Prints turn blue and last weeks to months

F. Ninhydrin • Choice of most examiners • Reacts w/ amino acids in sweat to produce purple prints (chemical) The Home Scientist - Ninhydrin • Very sensitive • Can develop 15 -year-old prints

G. Physical Developer • Most sensitive method • Reacts w/ sweat to form silver-gray print (Chemical) • Destroys print; use as last resort – Washes away proteins

VIII. Proper Collection of F. P. • Step 1: Loc. documented, object photographed Mythbusters - Fingerprints • Step 2: – Small Object: taken back to lab, F. P. developed, photographed, and lifted – Large Object: F. P. developed, photographed and lifted at crime scene