a1e4991f9e3940e4f8751e94cee13218.ppt
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Chapter 4: Fingerprints “Fingerprints can not lie, but liars can make fingerprints. ” —Unknown Kendall/Hunt Publishing Company
Fingerprints Students will learn: § Why fingerprints are individual evidence. Chapter 4 Kendall/Hunt Publishing Company 1
Fingerprints Students will be able to: § Define three basic properties that allow individual identification by fingerprints. § Obtain an inked, readable fingerprint for each finger. Chapter 4 Kendall/Hunt Publishing Company 2
Fingerprints § Recognize the general ridge patterns (loops, whorls, and arches) § Identify friction ridge characteristics and compare two fingerprints with at least ten points of identification. Chapter 4 Kendall/Hunt Publishing Company 3
Fingerprints § Explain the differences among latent, plastic, and visible fingerprints. § Develop latent prints (make them visible) using physical and chemical methods. Chapter 4 Kendall/Hunt Publishing Company 4
What is a fingerprint? LAn imprint made by ridge patterns on the tip of a finger LAlso used to describe the characteristic pattern of DNA fragments Chapter 4 Kendall/Hunt Publishing Company 5
Fingerprints Recording Prints: § Rolling inked prints § Primary identification number Chapter 4 Kendall/Hunt Publishing Company 6
Fingerprints Chapter 4 Kendall/Hunt Publishing Company 7
Fingerprints Lifting Prints § Black, white and fluorescent powder § Chemicals: ninhydrin, iodine, silver nitrate, cyanoacrylate Chapter 4 Kendall/Hunt Publishing Company 8
Fingerprints Other Types of Prints § Palm, lip, teeth, eye, ear, voice, shoe and footprints Chapter 4 Kendall/Hunt Publishing Company 9
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 Chapter 4 Kendall/Hunt Publishing Company 10
Dactyloscopy The study of fingerprints § Alphonse Bertillon—proposed body measurements as a means of identification; termed anthropometry § Francis Galton—developed a primary classification scheme based on loops, arches and whorls. Chapter 4 Kendall/Hunt Publishing Company 11
Dactyloscopy The study of fingerprints § Edward Richard Henry—in collaboration with Galton instituted a numerical classification system Chapter 4 Kendall/Hunt Publishing Company 12
Dactyloscopy The study of fingerprints § Juan Vucetich—developed a fingerprint classification based on Galton’s that is used in Spanish-speaking countries Chapter 4 Kendall/Hunt Publishing Company 13
Fundamental Principles of Fingerprints § A fingerprint is an individual characteristic. Chapter 4 Kendall/Hunt Publishing Company 14
Fundamental Principles of Fingerprints § A fingerprint will remain unchanged during an individual’s lifetime. Chapter 4 Kendall/Hunt Publishing Company 15
Fundamental Principles of Fingerprints § Fingerprints have general characteristic ridge patterns that permit them to be systematically classified Chapter 4 Kendall/Hunt Publishing Company 16
Ridge Characteristics Minutiae: § Characteristics of ridge patterns § The term used to define common micro features in a fingerprint. Chapter 4 Kendall/Hunt Publishing Company 17
Ridge Characteristics Chapter 4 Kendall/Hunt Publishing Company 18
Ridge Characteristics § Ridge ending Chapter 4 Kendall/Hunt Publishing Company 19
Ridge Characteristics § Dot or fragment Chapter 4 Kendall/Hunt Publishing Company 20
Ridge Characteristics § Eye or Enclosure Chapter 4 Kendall/Hunt Publishing Company 21
Ridge Characteristics § Bifurcation: A splitting line. Chapter 4 Kendall/Hunt Publishing Company 22
Ridge Characteristics § Bridge § Enclosure § Spur Chapter 4 Kendall/Hunt Publishing Company 23
Fingerprint Minutiae Chapter 4 Kendall/Hunt Publishing Company 24
Fingerprint Patterns Chapter 4 Kendall/Hunt Publishing Company 25
Arch - 5% 1. Has friction ridges that enter on one side of the finger and cross to the other side while rising upward in the middle. Chapter 4 Kendall/Hunt Publishing Company 26
Arch - 5% 2. They do NOT have type lines, deltas, or cores. Chapter 4 Kendall/Hunt Publishing Company 27
Arch - 5% Types § Plain § Tented Chapter 4 Kendall/Hunt Publishing Company 28
Arch - 5% Plain Chapter 4 Kendall/Hunt Publishing Company 29
Arch - 5% Tented Chapter 4 Kendall/Hunt Publishing Company 30
Loop – 65% Chapter 4 1. Must have one or more ridges entering and exiting from the same side. Loops must have one delta. Kendall/Hunt Publishing Company 31
Loop – 65% 2. Types § Radial: Opens toward the thumb § Ulnar: Opens toward the “pinky” (little finger) Chapter 4 Kendall/Hunt Publishing Company 32
Loop – 65% Ulnar Loop Chapter 4 Kendall/Hunt Publishing Company 33
Loop – 65% Radial Loop Chapter 4 Kendall/Hunt Publishing Company 34
Whorl – 30 -35% 1. Types § Plain § Central Pocket § Double Loop § Accidental Chapter 4 Kendall/Hunt Publishing Company 35
Whorl – 30 -35% 2. Whorls have at least two deltas and a core. Chapter 4 Kendall/Hunt Publishing Company 36
Whorl – 30 -35% 3. A plain or central pocket whorl has at least one ridge that makes a complete circuit. Chapter 4 Kendall/Hunt Publishing Company 37
Whorl – 30 -35% 4. A double loop is made of two loops. Chapter 4 Kendall/Hunt Publishing Company 38
Whorl – 30 -35% 5. An accidental is a pattern not covered by other categories. Chapter 4 Kendall/Hunt Publishing Company 39
Whorl – 30 -35% Chapter 4 Kendall/Hunt Publishing Company 40
Identify the Pattern Tented Arch Chapter 4 Kendall/Hunt Publishing Company 41
Identify the Pattern Plain Whorl Chapter 4 Kendall/Hunt Publishing Company 42
Identify the Pattern Central Pocket Chapter 4 Kendall/Hunt Publishing Company 43
Primary Classification The Henry—FBI Classification: Each finger is given a point value Chapter 4 Kendall/Hunt Publishing Company 44
Primary Classification right Chapter 4 left Kendall/Hunt Publishing Company 45
Primary Classification Assign the number of points for each finger that has a whorl and substitute into the equation: Chapter 4 Kendall/Hunt Publishing Company 46
Primary Classification right index right ring right thumb right middle Chapter 4 left thumb right little left middle little left index Kendall/Hunt Publishing Company left ring +1 +1 47
Primary Classification That number is your primary classification number Chapter 4 Kendall/Hunt Publishing Company 48
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. Chapter 4 Kendall/Hunt Publishing Company 49
Latent Prints 1. Those that are not visible to the naked eye. 2. These prints consist of the natural secretions of human skin and require development for them to become visible. Chapter 4 Kendall/Hunt Publishing Company 50
Latent Prints 3. Most secretions come from three glands: § Eccrine § Apocrine § Sebaceous Chapter 4 Kendall/Hunt Publishing Company 51
Latent Prints A. Eccrine: 1. Largely water with both inorganic (ammonia, chlorides, metal ions, phosphates) and organic compounds (amino acids, lactic acids, urea, sugars). Chapter 4 Kendall/Hunt Publishing Company 52
Latent Prints A. Eccrine: 2. Most important for fingerprints. Chapter 4 Kendall/Hunt Publishing Company 53
Latent Prints B. Apocrine: Secrete pheromones and other organic materials. Chapter 4 Kendall/Hunt Publishing Company 54
Latent Prints C. Sebaceous: Secrete fatty or greasy substances. Chapter 4 Kendall/Hunt Publishing Company 55
Developing Latent Prints § Developing a print requires substances that interact with secretions that cause the print to stand out against its background. Chapter 4 Kendall/Hunt Publishing Company 56
Developing Latent Prints § It may be necessary to attempt more than one technique, done in a particular order so as not to destroy the print. Chapter 4 Kendall/Hunt Publishing Company 57
Developing Latent Prints § Powders: Adhere to both water and fatty deposits. Choose a color to contrast the background. Chapter 4 Kendall/Hunt Publishing Company 58
Developing Latent Prints § Iodine: Fumes react with oils and fats to produce a temporary yellow brown reaction. Chapter 4 Kendall/Hunt Publishing Company 59
Iodine Fingerprint Chapter 4 Kendall/Hunt Publishing Company 60
Developing Latent Prints § Ninhydrin: Reacts with amino acids to produce a purple color. Chapter 4 Kendall/Hunt Publishing Company 61
Ninhydrin Fingerprint Chapter 4 Kendall/Hunt Publishing Company 62
Developing Latent Prints § Silver nitrate: Reacts with chloride to form silver chloride, a material which turns gray when exposed to light. Chapter 4 Kendall/Hunt Publishing Company 63
Developing Latent Prints § Cyanoacrylate: “Super glue” fumes react with water and other fingerprint constituents to form a hard, whitish deposit. Chapter 4 Kendall/Hunt Publishing Company 64
Cyanoacrylate Fingerprints Chapter 4 Kendall/Hunt Publishing Company 65
Developing Latent Prints § In modern labs and criminal investigations, lasers and alternative light sources are used to view latent fingerprints. Chapter 4 Kendall/Hunt Publishing Company 66
Developing Latent Prints § These were first used by the FBI in 1978. § Since lasers can damage the retina of the eye, special precautions must be taken. Chapter 4 Kendall/Hunt Publishing Company 67
Other Prints § Ears: Shape, length and width § Voice: Electronic pulses measured on a spectrograph Chapter 4 Kendall/Hunt Publishing Company 68
Other Prints § Foot: Size of foot and toes; friction ridges on the foot Chapter 4 Kendall/Hunt Publishing Company 69
Other Prints § Shoes: Can be compared and identified by type of shoe, brand, size, year of purchase, and wear pattern. Chapter 4 Kendall/Hunt Publishing Company 70
Other Prints Palm: Friction ridges can be identified and may be used against suspects. Chapter 4 Kendall/Hunt Publishing Company 71
Other Prints Footprints are taken at birth as a means of identification of infants. Chapter 4 Kendall/Hunt Publishing Company 72
Other Prints Lips: Display several common patterns Chapter 4 Kendall/Hunt Publishing Company 73
Other Prints § Short vertical lines § Short horizontal lines § Crosshatching § Branching grooves Chapter 4 Kendall/Hunt Publishing Company 74
Other Prints Chapter 4 Kendall/Hunt Publishing Company 75
Other Prints Teeth: A. Bite marks are unique and can be used to identify suspects. Chapter 4 Kendall/Hunt Publishing Company 76
Other Prints B. These imprints were placed in gum and could be matched to crime scene evidence. Chapter 4 Kendall/Hunt Publishing Company 77
Other Prints The blood vessel patterns in the eye may be unique to individuals. They are used today for various security purposes. Chapter 4 Kendall/Hunt Publishing Company 78
AFIS § The Automated Fingerprint Identification System: A computer system for storing and retrieving fingerprints Chapter 4 Kendall/Hunt Publishing Company 79
AFIS § Began in the early 1970’s to: A. Search large files for a set of prints taken from an individual Chapter 4 Kendall/Hunt Publishing Company 80
AFIS B. Compare a single print, usually a latent print developed from a crime scene Chapter 4 Kendall/Hunt Publishing Company 81
AFIS § 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 Chapter 4 Kendall/Hunt Publishing Company 82
AFIS § IAFIS: The FBI’s Integrated Automated Fingerprint Identification system which is a national database of all 10 -print cards from all over the country Chapter 4 Kendall/Hunt Publishing Company 83
Biometrics § Use of some type of body metrics for the purpose of identification. Chapter 4 Kendall/Hunt Publishing Company 84
Biometrics § Used today in conjunction with AFIS § Examples include retinal or iris patterns, voice recognition, hand geometry Chapter 4 Kendall/Hunt Publishing Company 85
Biometrics § 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. Chapter 4 Kendall/Hunt Publishing Company 86
a1e4991f9e3940e4f8751e94cee13218.ppt