Fingerprints

2. Fingerprints

3. History of Fingerprints Bertillon’s Method of Body Measurements - anthropology

4. Bertillon’s Method Developed by Alphonse Bertillon in 1883 Used by police for 20 years

5. Early Use of fingerprints Chinese used fingerprints to sign legal documents over 3000 years ago.

6. Several years before Bertillon’s work, Herschel was requiring India natives to sign contracts with the imprint of their right hand

7. In 1880, Fraud suggested that skin ridge patterns could be important for identifying criminals. Told the story of a thief who left his print on a white wall at the crime scene. They compared it with the suspect and it wasn’t his. A few days latter they had a new suspect, the print matched. When confronted, the suspect confessed.

8. Early Classification of fingerprints In 1892, Francis Galton published his book called Finger Prints It discussed the anatomy of fingerprints It suggested ways to record them It assigned them 3 pattern types Loops Arches Whorls

9. It demonstrated that no two prints are identical It said that prints remain the same year to year At Galton’s request, the British government adopted fingerprinting as a supplement to Bertillon’s system

10. Adoption of fingerprints Bertillon’s System was not perfect In 1903, Will West was sent to Fort Leavenworth prison. A check of the prison files showed that there was already a prisoner, William West. They could not distinguish between the two prisoners based on body measurements or photographs. They looked like twins.

11. Their fingerprints could tell them apart

12. In 1904, several American police officials received fingerprint identification instruction at the St. Louis World’s Fair

13. Fingerprinting began to be used in all major US cities after the St. Louis World’s fair and the Will West incident

14. In 1924, the Bureau of Investigations and Leavenworth merged their fingerprint records forming the identification records of the new Federal Bureau of Investigations The largest record for fingerprints in the world is held by the FBI

15. 3 Principle for fingerprints Principle ONE: A Fingerprint is an individual characteristic; No two fingers have yet been found to possess identical ridge characteristics

16. Principle TWO: A fingerprint remains unchanged during an individual’s lifetime Principle THREE: Fingerprints have general ridge patterns that permit them to be systematically classified

17. Principle ONE: Out of the millions of people who have had their fingerprints taken in the last 150 years, no two have ever been found identical The FBI has over 50 million classified prints and has not found identical prints

18. Ridge characteristics are studied to determine the individuality of a fingerprint In order for two prints to be a match, characteristics must be the same and the location must be the same The average fingerprint has 150 individual ridge characteristics

19. Most prints recovered at a crime scene are partial impressions Fingerprint analysts can compare only a small number of ridge characteristics It has never been determined how many characteristics are enough to make a comparison, the final determination must be based on experience and knowledge of the expert.

20. Principle TWO: Fingerprints are a reproduction of friction skin ridges found on the palm side of the fingers and thumbs.

21. Similar friction skin can be found on palms and soles of feet

22. These surfaces have been designed by nature to provide a firmer grip and resistance to slippage Prints consist of hills(Ridges) andvalleys(grooves) Ridges form the black lines from an ink fingerprint

23. Skin is composed of layers Outer layer is called the Epidermis Inner layer is called the Dermis Separating layer is called the Dermal Papillae

24. Dermal papillae determines the form and pattern of ridges on the surface of skin Epidermis Papillae Dermis

25. Sweat pores on the surface of the skin are attached to sweat glands The glands release perspiration on the surface of the skin Oilpicked up by touching the hairy parts of the body

26. Perspiration and oil are transferred onto surface leaving a print of the finger ridges These prints are invisible to the eye and are called latent prints

29. Attempts to change fingerprints A cut deep enough into the papillae will leave a scar A scar only becomes another identifiable characteristic. Not helpful to criminal.

30. Acid has been used to destroy a fingerprint. John Dillinger tried to destroy his prints with acid however his prints after the scarring still had similar characteristics to his prints before the scarring.

32. Extreme measure have been taken Picture may be disturbing!

35. Principle THREE: Fingerprints are divided into 3 classes Loops - 60-65% of people have loops Whorls - 30-35% of people have whorls Arches - 5% of people have arches

36. Loops Must have one or more ridges entering from one side, recurving and exiting on the same side Ulnar Loop Loop that opens up toward the little finger Radial Loop Loop that opens up toward the thumb

37. Type Lines The two diverging ridges Delta Ridge directly in front of the type line divergence (Greek letter Δ) Core The center of the pattern Core Type line Delta Type line

38. Whorls Must have type lines and at least 2 deltas Divided into 4 distinct Groups Plain Central pocket loop Double loop Accidental

39. Plain Have at least one ridge that makes a complete circuit Ridge may be in the form of a spiral, oval or other variant circle

40. Central Pocket loop Have at least one ridge that makes a complete circuit Ridge may be in the form of a spiral, oval or other variant circle

41. Difference between Plain Whorl and Central Pocket loop If you draw a line between the two deltas and the line touches a spiral ridge, the print is a plain whorl. If it does not touch a spiral ridge the print is a central pocket loop.

42. Plain Whorl Central Pocket loop

43. Double loop Made up of 2 loops in one print

44. Accidental loop Consists of a combination of two or more patterns or a pattern not covered by other categories

45. Arches Ridges rise like a wave or a tent Do not have type lines, deltas or cores

46. Arches are divided into 2 groups Plain rises in the middle like a wave Tented rises in the middle like a tent

47. Try It!!! 1. Loop 3. 2. Tented Arch Plain Whorl

49. Classification of Fingerprints FBI System Includes several different methods of classification in order to accommodate all the prints in the system

50. One method is part of the original method called the Henry system In this method, you pair up the fingers in fractions and assign numbers to each pattern R. Index R. Ring L. Thumb L. Middle L. Little R. Thumb R. Middle R. Little L. Index L. Ring