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Fingerprinting

Fingerprinting. Objectives. Discuss the history of fingerprinting Describe the characteristics of fingerprinting Identify the basic types of fingerprints Describe how criminals attempt to alter their fingerprints Determine the reliability of fingerprints as a means of identification

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Fingerprinting

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  1. Fingerprinting

  2. Objectives • Discuss the history of fingerprinting • Describe the characteristics of fingerprinting • Identify the basic types of fingerprints • Describe how criminals attempt to alter their fingerprints • Determine the reliability of fingerprints as a means of identification • Explain how fingerprint evidence is collected • Describe the latest identification technologies • Determine if a fingerprint matches a fingerprint on record • Use the process of lifting a latent print

  3. Introduction • Mark Twain’s (1984) fictional character, a lawyer (Puddn’head Wilson) stated: • Every human being carries with him from his cradle to his grave, certain physical marks which do not change their character, and by which he can always be identified– and that without shade of doubt or question. These marks are his signature, his physiological autograph, so to speak, and this autograph cannot be counterfeited, or can he disguise it or hide it away, nor can it become illegible by the wear and mutations of time.

  4. History of Fingerprinting How long have we known about fingerprints? • Seen in ancient cultures- using fingerprints as markings • Found in clay tablets dating back to 1792 B.C. in Babylon • In ancient China, fingerprints were used on official documents (e.g. contracts and loans)

  5. Historical Development In Western cultures, records from 1684 show fingerprint patterns being studied Documentation of fingerprint analysis under microscopes (1788) Jan Evangelist Purkyn describe 9 fingerprint patterns such as loops, spirals, circles, and double whorls Sir William Herschel noted that patterns differ from each person and do not change with age.

  6. Anthropometric System Bertillonage (1879) • Alphonse Bertillon created a way to identify criminals • First used in 1883 to identify a repeating offender • ALSO, first person to document incoming prisoners with a photograph- the forerunner of the modern mug shot

  7. ACTIVITY- Create your Bertillon Card Get together with your group, acquire a ruler, string, and appropriate cards for males and females. • Read the yellow handout • Measure you and your group’s measurements • Create your Bertillon Card • Once you are finished, you may begin the questions. Answer in a separate sheet of paper. This is homework, and due on Monday.

  8. History of Fingerprinting Classification System Early example of ten card • Sir Francis Galton and Sir E.R. Henry • 1888- developed the classification system that is still used in the US and Europe today

  9. History of Fingerprints Ivan (Juan) Vucetich Sir Edmund Richard Henry Divided up fingerprints based on characteristics of an arch, whorl, or loop pattern Each card had 10 fingerprints of a person • Improved fingerprint collection • 1891- noted measurements on ID cards of all arrested persons AND their 10 fingerprints • Devised a better way to take impressions

  10. DID YOU KNOW? • Fingerprints can be taken from dead bodies by chemically treating the fingertips to help them puff out. Another method involves surgically removing the finger skin and placing it like a glove into the finger of someone else, who can then roll the print

  11. Activity: Inspect your fingerprint • Obtain one balloon • Find a lab table • Place the balloon on the table, flat • Place your thumb on the ink pad • Roll your thumb onto the balloon (careful not to smudge!) • Inflate the balloon and tie

  12. Characteristics of Fingerprints • Loops • Whorls • Arches • Core • Delta • Ridge Count Area

  13. Characteristics • Arches: have ridges that enter from one side of the fingerprint and leave from the other side with a rise in the center

  14. Characteristics • Whorls: look like a bull’s eye, with two deltas (triangles)

  15. Characteristics • Loops: enter from either the right or the left and exit from the same side they enter

  16. Inspect your balloon • Determine the pattern you see in your fingerprint of your thumb. • Determine the pattern you see in your neighbor’s fingerprint.

  17. Inspect Fingerprints

  18. Activity: Study your Fingerprints • Follow the instructions on the yellow sheet, Activity 6-1.

  19. What are Fingerprints? • Look at the surface of your fingers • Are they smooth? Shiny? • NO • All fingers, toes, feet, and palms have small ridges- arranged in connected units called dermal (or friction) ridges

  20. What are Fingerprints? • The dermal ridges help us grip • When the ridges are pressed against things, they leave an impression mark (FINGERPRINT) • Imprint = consists of natural secretions or sweat glands that are present in the ridge of the skin

  21. Secretions  Fingerprint • Secretions= oils, water, and salts + dirt from every day activities • Anytime you touch anything, you leave traces of these substances in a unique pattern of your dermal ridges

  22. Formation of Fingerprints • The nature of fingerprints has been known for 2000 years • Scientists recently realized they originate from the womb • Pattern are probably form in the 10th week of pregnancy • Fetus = 3 inches long

  23. Creation of Fingerprints • In the basal layer (layer within the epidermis where new skin cells are produced) • Grows fastest in a fetus • Therefore, it folds in different directions, creating intricate shapes • Cannot be altered or destroyed permanently : outer layer protects it

  24. Did you know? • A symptom of two rare genetic conditions is the lack of fingerprints. Dermatopathiapigmentosareticularis (DPR) is so rare that only one family in the world is known to have it. Ectodermal dysplasia is a group of conditions related to skin disorders, including some people with the lack of fingerprints.

  25. Vocabulary • Arch: a fingerprint pattern in which the ridge • Core: a center of a loop or whorl • Delta: a triangular ridge pattern with ridges that go in different directions above and below a triangle • Fingerprint: An impression left on any surface that consists of patterns made by the ridges on a finger • Loop: a fingerprint pattern in which the ridge pattern flows inward and returns in the direction of the origin

  26. Vocabulary • Minutiae: the combination of details in the shapes and positions of the ridges in fingerprints that make each unique; also called ridge characteristics • Patent fingerprint: a visible fingerprint that happens when fingers with blood, ink, or some other substance on them touch a surface and transfer the pattern of their fingerprint to that surface • Plastic fingerprint: a 3dimentional fingerprint made in soft material such as clay, soap, or putty

  27. Vocabulary • Ridge pattern: the recognizable pattern of the ridges found in the end joints of fingers that form lines on the surfaces of objects in a fingerprint. They fall into three categories: arches, loops, and whorls • Ten card: a form used to record and preserve a person’s fingerprints • Whorl: a fingerprint pattern that resembles a bull’s eye

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