1. Forensic Science: Fundamentals & Investigations, Chapter 6 1 Fingerprints By the end of this chapter you will be able to: discuss the history of fingerprinting describe the characteristics of fingerprints and fingerprinting minutiae explain when and how fingerprints are formed describe what causes fingerprints to be left on objects identify the basic types of fingerprints describe how criminals attempt to alter their fingerprints All Rights Reserved South-Western / Cengage Learning © 2009

2. Forensic Science: Fundamentals & Investigations, Chapter 6 2 Fingerprints By the end of this chapter you will be able to: determine the reliability of fingerprints as a means of identification describe the Integrated Automated Fingerprint Identification System (IFAIS) 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. Dactyloscopy Dactyloscopy is the study of fingerprints. Police investigators are experts in collecting “dactylograms”, otherwise known as fingerprints. Forensic Science: Fundamentals & Investigations, Chapter 6 3

4. 4 Historical Development 1. In ancient Babylon (dating back to 1792-1750 B.C.), fingerprints pressed into clay tablets marked contracts. 2. The documents showing fingerprints date from third century B.C. China. 3. The earliest written study (1684) is Dr. Nehemiah’s paper describing the patterns he saw on human hands under a microscope, including the presence of ridges. 4. In 1788, Johann Mayer noted that the arrangement of skin ridges is never duplicated in two persons. He was probably the first scientist to recognize this fact.

5. Forensic Science: Fundamentals & Investigations, Chapter 6 5 Historical Development 5.Nine fingerprint patterns were described in 1823 by Jan Evangelist Purkyn. 6.Sir William Herschel (shown at the right), in 1856, began the collection of fingerprints and noted they were not altered by age. 7.Alphonse Bertillon created a way to identify criminals that was used in 1883 to identify a repeat offender. 8.In 1888, Sir Francis Galton (shown at the right), and Sir Edmund Richard Henry, developed the fingerprint classification system that is still in use in the United States.

6. Forensic Science: Fundamentals & Investigations, Chapter 6 6 Historical Development 9.In 1891, Iván (Juan) Vucetich improved fingerprint collection. He began to note measurements on identification cards, as well as adding all ten fingerprint impressions. He also invented a better way of collecting the impressions. 10.Beginning in 1896, Sir Henry (mentioned in the last entry on the previous slide), with the help of two colleagues, created a system that divided fingerprints into groups. Along with notations about individual characteristics, all ten fingerprints were imprinted on a card (called a ten card).

7. Forensic Science: Fundamentals & Investigations, Chapter 6 7 What Are Fingerprints? All fingers, toes, feet, and palms are covered in small ridges. These ridges are arranged in connected units called dermal, or friction, ridges. These ridges help us get or keep our grip on objects. Natural secretions plus dirt on these surfaces leave behind an impression (a print) on those objects with which we come in contact.

8. Forensic Science: Fundamentals & Investigations, Chapter 6 8 Formation of Fingerprints An animal’s external tissue (skin) consists of (a) an inner dermis and (b) an outer epidermis. The creation of fingerprints occurs in a special layer (the basal layer) in the epidermis where new skin cells are produced. Fingerprints probably begin forming at the start of the 10 th week of pregnancy. Because the basal layer grows faster than the others, it collapses, forming intricate shapes.

9. Cross-Section of Skin bsapp.com

10. Principles of Fingerprints First Principle: A fingerprint is an individual characteristic; no two fingers have yet been found to posses identical ridge characteristics. bsapp.com

11. Principles of Fingerprints Second Principle: A fingerprint will remain unchanged during an individual's lifetime. bsapp.com

12. Principles of Fingerprints Third Principle: Fingerprints have general ridge patterns that permit them to be systematically classified. bsapp.com

13. Forensic Science: Fundamentals & Investigations, Chapter 6 13 Characteristics of Fingerprints Forensic examiners look for the presence of a core (the center of a whorl or loop) and deltas (triangular regions near a loop). A ridge count is another characteristic that distinguishes one fingerprint from another. The count is made from the center of the core to the edge of the delta.

14. Forensic Science: Fundamentals & Investigations, Chapter 6 14 Characteristics of Fingerprints There are 3 general fingerprint distinctions: ARCH WHORL LOOP About 5% About 30% About 65% of the population

15. Arch An arch has friction ridges that enter on one side of the finger and cross to the other side while rising upward in the middle. They do NOT have type lines, deltas, or cores. Types  Plain  Tented Forensic Science: Fundamentals & Investigations, Chapter 6 15

16. Arches Plain Arch Ridges enter on one side and exit on the other side. Tented Arches Similar to the plain arch, but has a spike in the center. Spike or “tent”

17. Loop  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? Forensic Science: Fundamentals & Investigations, Chapter 6 ; Kendall/Hunt Publishing Co. 17

18. Loops These patterns are named for their positions related to the radius and ulna bones. Delta Ulnar Loop (Right hand) Loop opens toward right or the ulna bone. Radial Loop (Right hand) Loop opens toward the left or the radial bone. NOTE: On the left hand, a loop that opens to the left would be an ulnar loop, while one that opens to the right would be a radial loop.

19. Whorl  A plain or central pocket whorl has at least one ridge that makes a complete circuit. A double loop is made of two loops. An accidental is a pattern not covered by other categories. Whorls have at least two deltas and a core.  Types  Plain, Central Pocket, Double Loop, Accidental Forensic Science: Fundamentals & Investigations, Chapter 6 ; Kendall/Hunt Publishing Co. 19

20. Whorls If a print has more than two deltas, it is most likely an accidental. Draw a line between the two deltas in the plain and central pocket whorls. If some of the curved ridges touch the line, it is a plain whorl. If none of the center core touches the line, it is a central pocket whorl. Plain Whorl Central Pocket Whorl

21. Whorls – Part 2 Accidental Whorl Accidental whorls contain two or more patterns (not including the plain arch), or does not clearly fall under any of the other categories. Double Loop Whorl Double loop whorls are made up of any two loops combined into one print. Delta

22. Identify each fingerprint pattern. Right Hand Left Hand Right Hand

23. Forensic Science: Fundamentals & Investigations, Chapter 6 23 Characteristics of Fingerprints Basic patterns can be further divided: – Arch patterns can be plain (4%) or tented (1%). – Whorl patterns can be central pocket (2%), double loop (4%), or accidental (0.01%). Even twins have unique fingerprints due to small differences (called minutiae) in the ridge patterns.

24. Ridgeology: The study of the uniqueness of friction ridge structures and their use for personal identification. 1 1 Introduction to Basic Ridgeology by David Ashbaugh, May 1999 Image from http://www.cs.usyd.edu.au/~irena/minutia.gif The koala is one of the few mammals (other than primates) that has fingerprints. In fact, koala fingerprints are remarkably similar to human fingerprints; even with an electron microscope, it can be quite difficult to distinguish between the two. Ridgeology

25. Ridge Characteristics Use these characteristics as points of identification when comparing fingerprint samples. The more points you can find in common, the better the match!

26. Fingerprint Minutiae- characteristics of ridge patterns Forensic Science: Fundamentals & Investigations, Chapter 6 26

27. http://cnx.org/content/m12574/latest/properties.jpg Ridge Characteristics Crossover Core Bifurcation (fork) Ridge ending Island Delta Pore Scar

28. Kendall/Hunt Publishing Company 28 Primary Classification The Henry—FBI Classification Each finger is given a point value rightleft

29. Kendall/Hunt Publishing Company 29 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 =

30. Fingerprint Identification When minutiae on two different prints match, these are called points of similarity or points of identification. At this point there is no international standard for the number of points of identification required for a match between two fingerprints. However, the United Kingdom requires a minimum sixteen points while Australia requires twelve. 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. Fingerprint Identification

31. Kendall/Hunt Publishing Company 31 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

32. Forensic Science: Fundamentals & Investigations, Chapter 6 32 Types of Fingerprints There are 3 types of prints that investigators look for at crime scenes: 1. Patent fingerprints are visible prints transferred onto smooth surfaces by blood or other liquids. 2. Plastic fingerprints are indentations left in soft materials such as clay or wax. 3. Latent fingerprints are not visible but made so by dusting with powders or the use of chemicals.

33. Kendall/Hunt Publishing Company 33 Latent Prints  Latent fingerprints are those that are not visible to the naked eye. These prints consist of the natural secretions of human skin and require development for them to become visible.  Most secretions come from three glands:  Eccrine—largely water with both inorganic (ammonia, chlorides, metal ions, phosphates) and organic compounds (amino acids, lactic acids, urea, sugars). Most important for fingerprints.  Apocrine—secrete pheromones and other organic materials.  Sebaceous—secrete fatty or greasy substances.

34. Kendall/Hunt Publishing Company 34 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.  Iodine—fumes react with oils and fats to produce a temporary yellow brown reaction.

35. Kendall/Hunt Publishing Company 35 Developing Latent Prints  Ninhydrin—reacts with amino acids to produce a purple color.  Silver nitrate—reacts with chloride to form silver chloride, a material which turns gray when exposed to light.  Cyanoacrylate—“super glue” fumes react with water and other fingerprint constituents to form a hard, whitish deposit. 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. Since lasers can damage the retina of the eye, special precautions must be taken.

36. Kendall/Hunt Publishing Company 36 Iodine Fingerprint

37. Kendall/Hunt Publishing Company 37 Ninhydrin Fingerprint

38. Kendall/Hunt Publishing Company 38 Cyanoacrylate Fingerprints

39. Forensic Science: Fundamentals & Investigations, Chapter 6 39 Fingerprint Forensic FAQs How are latent fingerprints collected?

40. Forensic Science: Fundamentals & Investigations, Chapter 6 40 Fingerprint Forensic FAQs Can fingerprints be erased? No, if, for example, they are removed with chemicals, they will grow back. Is fingerprint identification reliable? Yes, but analysts can make mistakes. Is fingerprint matching carried out by computers in a matter of seconds? No, but the FBI’s Integrated Automated Fingerprint Identification System (IAFIS or AFIS) can provide a match in 2 hours for the prints in its Master File.

41. Kendall/Hunt Publishing Company 41 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.

42. Kendall/Hunt Publishing Company 42 Other Prints Palm—friction ridges can be identified and may be used against suspects.

43. Kendall/Hunt Publishing Company 43 Other Prints Footprints are taken at birth as a means of identification of infants.

44. Kendall/Hunt Publishing Company 44 Other Prints Lips—display several common patterns  Short vertical lines  Short horizontal lines  Crosshatching  Branching grooves

45. Kendall/Hunt Publishing Company 45 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.

46. Kendall/Hunt Publishing Company 46 Other Prints The blood vessel patterns in the eye may be unique to individuals. They are used today for various security purposes.

47. Kendall/Hunt Publishing Company 47 Biometrics  Use of some type of body metrics for the purpose of identification. (The Bertillon system may actually have been the first biometry system.)  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.

48. Forensic Science: Fundamentals & Investigations, Chapter 6 48 The Future of Fingerprinting New scanning technologies and digitally identifying patterns may eliminate analytical mistakes. Trace elements of objects that have been touched are being studied to help with the identification of individuals. To help with identification, other physical features such as eyes and facial patterns are also being studied.

49. Forensic Science: Fundamentals & Investigations, Chapter 6 49................. Summary................. Summary Fingerprints have long been used for identification, and in the mid-1800s were recognized as unique to each person. Three main groups include arches, whorls, and loops. Basic analysis includes looking for cores, deltas, and making a ridge count. Investigators search for patent, plastic, and latent prints. Dusting with powders or using special chemicals can make latent fingerprints visible. New developments may eliminate errors by analysts.

50. Fingerprints See “Guide to Reading Prints” for the last 3 pages of notes Forensic Science: Fundamentals & Investigations, Chapter 6 50

51. It’s time to make some prints! Avoid Partial Prints GOOD PRINT Get as much of the top part of your finger as possible!

52. Directions 1 st – Roll the “pad” portion of your thumb over the ink pad from the left side of your thumb to the right. You do not have to push down really hard! 2 nd – Roll the “pad” portion of your thumb from the left side of your thumb to the right in the correct box on your paper to make a thumbprint. 3 rd – Continue this process to make a fingerprint of all ten fingers on the “My Prints” worksheet. 4 th –Use your notes and a magnifying lens to help you figure out what type of pattern is found in each of your fingerprints. Label each one with the pattern’s name.

53. T. Trimpe 2006 http://sciencespot.net Bsapp.com Kendall-Hunt Publishing Co. Cengage Learning