FINGERPRINTS

1. FINGERPRINTS Chapter 14

2. Students Will Be Able To: • Describe the formation of a fingerprint. • Discuss the history of fingerprinting.

3. “Today the fingerprint is the pillar of modern criminal identification.”

4. Dactylscopy • Is the study of fingerprints

5. Principles of Fingerprints • Is an individual characteristic • Will remain unchanged during an individual’s lifetime • Have general characteristic ridge patterns that permit them to be classified

6. History of Fingerprinting • Earliest records of using fingerprints date back to 1792-1750 BC in Babylon • Used to bind contracts • In China, fingerprints were used on contracts and loans • In 1788 Johann Christoph Andreas Mayer stated that no two people had the same ridge pattern • In 1823, Jan Purkyn described 9 distinct fingerprint patterns • Loops • Spirals • Circles • Double whorls

7. The History of Fingerprinting • Throughout history, there are six significant people involved in fingerprinting • William Herschel • Henry Faulds • Alphonse Bertillion • Francis Galton • Edward Richard Henry • Juan Vucetich

8. William Herschel • Began collecting fingerprints in 1856 • Said that patterns were unique to each person and were not altered by age • Required natives to sign contracts with imprint of right hand

9. Henry Faulds • Suggested that skin ridge patterns could be important for the identification of criminals

10. Alphonse Bertillion • Proposed body measurements as a means of identification • Field called anthropometry • System called for 11 measurements to be taken • Height, reach, width of head, length of each food are a few examples • Identification via anthropometry was replaced with fingerprints • No two people can have the same fingerprints; however, 2 people can have the same anthropometric measurements

12. Francis Galton • Verified that fingerprints do not change with age • Developed a primary classification scheme based on loops, whorls, and arches • Wrote a book called Finger Prints • States that a person’s fingerprints do not change over the years • His system was adopted by the British government • Was the first person credited with solving a murder using fingerprints

13. Edward Richard Henry • Worked with Galton to institute a numerical classification system to file fingerprints • English speaking countries including the US use Henry’s classification system • Also Devised the ten print card • All fingers are fingerprinted

15. Juan Vucetich • Developed a fingerprint classification based on Galton’s that is used in Spanish speaking countries

16. History Clip

17. Fingerprints • Fingerprints are a reproduction of friction skin ridges found on the palm side of the fingers and thumbs • Also found on the surface of the palms and the soles of the feet • Provide our bodies with a firm grasp and resistance to slippage

18. Fingerprints • Form in utero beginning at the 10th week of pregnancy • Creation happens in the basal layer of the epidermis • Skin cells grow more rapidly here than the epidermis on the outside and the dermis on the inside • Basal layer ends up collapsing and folding in different directions

19. Skin • Is composed of layers of cells • 2 main portions exist • Epidermis • Outer portion of the skin • Dermis • Inner portion of the skin • Dermal papillae separate the 2 portions • Shape of the boundary determines the form and pattern of the ridges

20. Skin • Each skin ridge has a row of pores • Are openings for ducts leading from the sweat gland • Perspiration and oils pass through these ducts • Is left behind when an object has been touched • This is the fingerprint

22. Where Do Fingerprints Come From Video Clip

23. Students Will Be Able To: • Describe the characteristics of fingerprints. • Identify the basic types of fingerprints.

24. Characteristics of Fingerprints • Two things a forensic examiner look for on a fingerprint are • Presence of a core • Is the center of the loop or whorl • Presence of a delta • Is a triangular region located near a loop • Also use a ridge count • Is the area from the delta to the core

26. Pattern Characteristics • All fingerprints are divided into three classes based on their pattern • Loops • Whorls • Arches

27. Loops • Must have one or more ridges entering and exiting from the same side • Must have one delta • 2 types • Radial- opens toward the thumb • Ulnar- opens toward the pinky • Occurs in 60-65% of the population

29. Whorls • Must have a type line, a core, and a minimum of 2 deltas • Divided into 4 groups • Plain- have at least one ridge that makes a complete circuit • Central pocket loop- have at least one ridge that makes a complete circuit • Double loop- made up of 2 loops combined into one fingerprint • Accidental- contains 2 or more patterns or is a pattern covered by the other categories • Occur in 30-35% of the population

32. Arches • Has friction ridges that enter on one side of the finger and cross to the other side while rising upward in the middle • Do not have type lines, deltas, or cores • 2 types • Plain- normal wavelike pattern • Tented- is the same as plain except that a sharp spike occurs at the center • Occur in 5% of the population

34. Your Turn

41. Ridge Characteristics • Must match in two fingerprints in order for their common origin to be established • No set limit on how many minutiae must match has been set • However, courts will accept 8-12 points of similarity • Also known as minutiae • Includes • Ridge ending • Short ridge • Dot or fragment • Bifurcation • Double bifurcation • Trifurcation • Bridge • Island • Enclosure • Spur

44. Students Will Be Able To: • Identify the importance of the Henry classification system for fingerprints. • Calculate the classification number of an individual with certain whorl patterns.

45. Primary Classification • The Henry- FBI classification system

46. Primary Classification • It will provide the fingerprint examiner with a number of candidates • System is only useful in cases when a full set of fingerprints is available

47. Primary Classification • Each finger is assigned a number of points if a whorl is present right right left left left index ring thumb middle little + 1 = right right right left left thumb middle little index ring +1

48. Primary Classification • The lowest primary classification a person can have is 1/1 0 + 0 + 0 + 0 + 0 + 1 = 1 0 + 0 + 0 + 0 + 0 + 1 1 If an individual has the lowest possible classification, you would immediately know that the person has loops or arches on all ten fingers and no whorls • The highest possible classification a person can have is 32/32 16 + 8 + 4 + 2 + 1 + 1 = 32 16 + 8 + 4 + 2 + 1 + 1 32 If an individual has the highest possible classification, you would immediately know that the person has whorls on all ten fingers

49. Students Will Be Able To: • Distinguish among visible, plastic, and latent fingerprints. • Explain how fingerprint evidence is collected. • List the techniques for developing latent fingerprints on porous and nonporous objects. • Describe the proper procedures for preserving a developed latent fingerprint.

50. Types of Prints • 3 types • Visible • Plastic • Latent