1. Chapter 4: Fingerprints “Fingerprints can not lie, but liars can make fingerprints.” —Unknown

2. Chapter 41 What Are Prints?  Any impression left behind in a medium that was made from another object, usually biological  Examples: Palm, lip, teeth, eye, ear, voice, shoe and footprints  Our skin has pores that oils seep through and deposit in the valleys of our prints. When you touch something, you leave the oil from the valleys behind.  Techniques have been developed to lift these oils off the surface of the object without disturbing the pattern of the print.

3. Chapter 42 Dactyloscopy The study of fingerprints Historically  William Herschel—required Indians to put their fingerprints on contracts, and also as a means of identifying prisoners  Henry Faulds—claimed that fingerprints did not change over time and that they could be classified for identification  Alphonse Bertillon—proposed body measurements as a means of identification; termed anthropometry  Precursor to fingerprint ID  Francis Galton—developed a primary classification scheme based on loops, arches and whorls  Publishes “No two prints are identical”  Edward Richard Henry—in collaboration with Galton instituted a numerical classification system  Juan Vucetich—developed a fingerprint classification based on Galton’s that is used in Spanish-speaking countries  Thomas Jennings- first person convicted in US on fingerprint evidence  FS for Dummies- Case study- Pg 76

4. Chapter 43 Fundamental of Fingerprints  A fingerprint is an individual characteristic if you look at the specifics of the print.  If you look at the general classification, it’s a class characteristic.  Fingerprints have general characteristic ridge patterns that permit them to be systematically classified.  A fingerprint will remain unchanged during an individual’s lifetime.  Fingerprints are somewhat genetic, but even twins do not have the same print

5. Chapter 44 Classification  Whorls, arches and loops  Loop: ridges enter and exit the same side  Whorls: 2 deltas and a core  Arches: no delta or core  Delta- the center triangular pattern, only found in loops and whorls

6. Chapter 45 Ridge Characteristics  The lines on your fingerprints are ridges  Allow your fingerprints to have traction  Evolution- allow humans to work better with their hands  All primates have fingerprints  Identical twins are NOT the same…  The spaces in between are the grooves  The grooves are actually what leaves the print behind, the ridge is the white part of the print

7. Chapter 46 Ridge Characteristics Minutiae- ridge patterns  Ridge ending  Short ridge  Dot or fragment  Bifurcation  Double bifurcation  Trifurcation  Bridge  Island  Enclosure  Spur

8. Chapter 47 Fingerprint Minutiae

9. Chapter 48 Arch- 5%  Enter one side, leave the other and ‘lump’ in the middle.  They do NOT have type lines, deltas, or cores.  Least common Types  Plain  Tented

10. Chapter 49 Loop- 65%  A loop must have one or more ridges entering and exiting from the same side. Loops must have one delta.  Types  Radial—opens toward the thumb  Ulnar—opens toward the “pinky” (little finger)  Which type of loop is this, if it is on the right hand? Left hand?

11. Chapter 410 Whorl- 30%  Whorls have at least two deltas and a core.  Types  Plain- bull’s eye  Central Pocket- loop with a whorl at the end  Double Loop- two loops that make an s-shape  Accidental- irregular

12. Chapter 411 The Henry System  Developed by Sir Edward Henry- Inspector general of British Police in India  System developed in 1899 is still used today in US and Britain  Prints get scores, total score narrows down the search  Like we did in class  There are 1024 groups of fingerprints in the system

13. Chapter 412 Primary Classification The Henry—FBI Classification Each finger is given a point value rightleft

14. Chapter 413 Primary Classification Assign the number of points for each finger that has a whorl and substitute into the equation: right right left left left index ring thumb middle little + 1 right right right left left thumb middle little index ring +1 That number is your primary classification number =

15. Chapter 414 Comparison There are no legal requirements in the United States on the number of points. Generally, criminal courts will accept 8 to 12 points of similarity.

16. Chapter 415 Many Types of Prints  Plastic Prints- putty, paint, soap, candle wax, gum, etc (anything soft)  Visible prints- left by a finger with a colored material on it (blood, ink, paint, dirt or grease)  Latent prints- invisible and must be developed by chemical means (needs special lighting to see)

17. Chapter 416 Latent Prints  All fingerprints are made of the natural secretions of human skin  Therefore, if the prints are invisible, we must development them to become visible.  Most secretions come from three glands:  Eccrine— secretes lots of water and acids (like amino, lactic, urea). Most important for fingerprints because they react easily to developer chemicals.  Apocrine—secrete pheromones  Sebaceous—secrete fatty or greasy substances.

18. Chapter 417 Anatomy of Prints  Besides chemicals, skin is also a component of fingerprints.  Prints are made of epidermal layers of skin  Chemically erasing prints (John Dillinger) will not work  Video Video

19. Chapter 418 Developing Latent Prints  Developing a print requires substances that interact with secretions that cause the print to stand out against its background.  It may be necessary to attempt more than one technique, done in a particular order so as not to destroy the print.  Powders—adhere to both water and fatty deposits. Choose a color to contrast the background.  Some magnetic powders, too  Iodine—fumes react with oils and fats to produce a temporary yellow brown reaction. Disadvantage- fades easily- so they spray it with starch to turn it blue (keeps it for months)

20. Chapter 419 Developing Latent Prints  Ninhydrin—reacts with amino acids to produce a purple color. Disadvantage- takes several hours to appear- but you can heat it to speed up the process  Silver nitrate—reacts with chloride to form silver chloride, a material which turns gray when exposed to light. Component of black and white film. The salt in the print reacts with the silver nitrate to form silver chloride which glows in UV light,  Cyanoacrylate—“super glue” fumes react with water and other fingerprint constituents to form a hard, whitish deposit. The print then glows under UV light or certain laser lights. Today, they have a hand held wand that secretes the fume automatically.  Digital Technology- More often, a print or partial in unclear. Prints are scanned and then enhanced/improved the clean up the print. In modern labs and criminal investigations, lasers and alternative light sources are used to view latent fingerprints. These were first used by the FBI in 1978. Think black light (the 70s…)

21. Chapter 420 Iodine Fingerprint

22. Chapter 421 Ninhydrin Fingerprint

23. Chapter 422 Cyanoacrylate Fingerprints

24. Chapter 423 Other Prints  Ears—shape, length and width  Voice—electronic pulses measured on a spectrograph  Foot—size of foot and toes; friction ridges on the foot  Shoes—can be compared and identified by type of shoe, brand, size, year of purchase, and wear pattern.

25. Chapter 424 Other Prints Palm—friction ridges can be identified and may be used against suspects.

26. Chapter 425 Other Prints Footprints are taken at birth as a means of identification of infants.

27. Chapter 426 Other Prints Lips—display several common patterns  Short vertical lines  Short horizontal lines  Crosshatching  Branching grooves

28. Chapter 427 Other Prints Teeth—bite marks are unique and can be used to identify suspects. These imprints were placed in gum and could be matched to crime scene evidence.

29. Chapter 428 Other Prints The blood vessel patterns in the eye may be unique to individuals. They are used today for various security purposes.

30. Chapter 429 AFIS  The Automated Fingerprint Identification System - a computer system for storing and retrieving fingerprints  Began in the early 1970’s to:  Search large files for a set of prints taken from an individual  Compare a single print, usually a latent print developed from a crime scene  By the 1990’s most large jurisdictions had their own system in place. The problem - a person’s fingerprints may be in one AFIS but not in others  IAFIS—the FBI’s Integrated Automated Fingerprint Identification system which is a national database of all 10-print cards from all over the country  FS for Dummies- Pg. 80

31. Chapter 430 Anthropometry  Use of some type of body metrics for the purpose of identification. (precursor to fingerprinting.)  Originated in studying the measurements of humans  Alphonse Bertillon developed it in 1883.  Based off the idea that skeletons don’t change after age 20, he created a system used to calculate the odds of two people having the same body measurements. Turns out, the odds are 286 million to one.  However, it was quickly abandoned because it required too exact of measurements  A form of it is used today in conjunction with AFIS  Examples include retinal or iris patterns, voice recognition, hand geometry  Other functions for biometrics—can be used to control entry or access to computers or other structures; can identify a person for security purposes; can help prevent identity theft or control social services fraud.

32. Chapter 431 More about Prints Myth Busters! For additional information about prints and crime, check out Court TV’s Crime Library www.crimelibrary.com/criminal_mind/forensics/fin gerprints/1.html