1. Forensic Aspects of Evidence
Fingerprint Identification
“Lifted” from Steve Gilbert, M.F.S., Ph.D.

2. History of Fingerprints
1684 – Nehemiah Grew reported that various patterns were present in the fingers
1685 – Bidloo produced first fingerprint drawing
1823 – Johannus Purkinje wrote a commentary of the skin system
1880 – Henry Faulds stated that chance prints at scenes could identify perpetrator (Faulds)

3. History of Fingerprints
1892 – Francis Galton wrote his book called “Fingerprints”. Studied over 40,000 prints and failed to find any matches
1901 – Sir Edward Henry established the first and continuing classification system
1902 – New York began collecting fingerprints of job applicants

4. History of Fingerprints
1903 – West Brothers case in Kansas
1904 – First fingerprint bureau
1905 – US Army began fingerprinting soldiers
1924 – FBI established FP system

5. Parts of the Hand Distal II III I IV Radial Ulnar Proximal
Inter Digital Intervals
Meta Carpal Crease
Thenar Eminence II
III
Inter Digital Pads I - IV I IV
Radial
Ulnar
Proximal Traverse Crease
Hypo Thenar Eminence
Distal Traverse Crease
Bracelet Crease
Proximal

6. Embryology 6 weeks: pads II, III, IV
8 weeks: finger elongate, separate
8-12 weeks: pads round, separate pads
13 weeks: pads regress smaller
3-4 months: ridges form
The number ridges dictated by fullness of finger pad

7. Pattern Anomalies Dissociation of Ridges – no ridges
Dysplasia – Faulty development of friction skin
Cuspal Patterns – ridges run distal to proximal rather than side to side

8. Loops
Loops opening towards the little finger is the ulnar loop, whereas the loop opening towards the thumb is the radial loop.
One or more ridges enter on either side, recurve, touch or pass an imaginary line drawn from the delta to core, and terminate or tend to terminate on or toward the same side the ridge or ridges entered.

9. Ridge Counting
Ridge count: 19 The line must touch the ridge to be counted.
The number of ridges intervening between the delta and the core is known as the ridge count. (yellow tick marks)

10. Plain Arch
Ridges enter on one side and flow or tend to flow out the other side with a rise or wave in the center.

11. Tented Arch
Ridges enter on one side and flow or tend to flow out the other side, however the ridges in the center do not. This possesses an angle.

12. Tented arch possessing the up-thrust.

13. Plain Whorls
If an imaginary line drawn between both deltas crosses or touches a recurving ridge in the inner pattern area, the pattern is consider a plain whorl.
The plain whorl has two deltas and at least one ridge making a complete circuit, which may be spiral, oval, circular, or any variant of a circle.

14. Central Pocket Loop
The central pocket loop has two deltas and at least one ridge which makes or tends to make a complete circuit. The circuit may be spiral, oval, circular or any variant of a circle. An imaginary line drawn between the two deltas must not touch or cross any recurving ridges within the inner pattern.

15. Double Loop
The double loop consists of two separate loop formations, with two separate and distinct sets of shoulders and two deltas.

16. Accidental
The accidental is a pattern consisting of a combination of two different types of patterns, with the exception of the plain arch, with two or more deltas; or a pattern which possesses some of the requirements for two or more different types; or a pattern which conforms to none of the definitions.

17. Major Parts of Prints
Pattern area: appears in a loop or whorl in which appear the cores, deltas and ridges
Core: approximate center of the print
Delta: that point on a ridge at or in front of and nearest the center of the divergence of the type lines

18. Pattern Area

19. Core and Delta
Core
Delta

20. Fingerprint Classification Henry System
Key Major Primary Secondary Subsecondary final
M U IOI
L U IOI
Sample classification

21. Primary Classification
Primary: Values of whorls Finger value assignments: Fingers 1 & 2: 16 Fingers 3 & 4: 8 Fingers 5 & 6: 4 Fingers 7 & 8: 2 Fingers 9 & 10: 1
1 is added to all primary classifications
1 over 1 indicates no whorls
32 over 32 indicates no whorls

22. Primary Classification
Where whorls appear in the fingers, the values are added, even over odd, with 1 added to the total. In this card, the right hand has =29 The left hand: =19
Even fingers
Odd fingers

23. Secondary Classification
Secondary: the pattern appearing in the index fingers A Arch T Tented Arch R Radial Loop U Ulnar Loop W Whorl

24. Subsecondary Classification
Subsecondary: grouping according to the ridge counts of loops and ridge tracings of whorls

25. Major Classification
Major: Where whorls appear in the thumbs, the major division reflects whorl tracings (inner, outer, meeting)
If loops appear in the thumbs, ridge counts are used

26. Major Classification Table
Left Thumb Denominator Right Thumb Numerator
01-11 Small………………………..[01-11, Small]
[12-16, Medium]
[17+, Large]
12-16 Medium…………………….. [01-11, Small]
17 or more, Large…………………..[01-17, Small]
[18-22, Medium]
[23+, Large]

27. Final Classification
Final: ridge count of the right little finger. *If not: ridge count in the left little finger *If not: a whorl is used * left delta to core (right hand) * right delta to core (left hand)

28. Key Classification
Key: ridge count of the first loop appearing on the fingerprint card, exclusive of little fingers

29. Fingerprint Processing
Powder and brush
Physical developer
Small particle developer
Ninhydrin
Cyanoacrylate
Iodine crystals
The following images depict laboratory practicums of the junior Fingerprints and Impressions class.

30. Powder and Brush

31. Powder and Brush
A camel hair brush is used to apply the fingerprint powder on suspect areas.

32. Powder and Brush
Once a print is developed, excess powder is brushed away, leaving a visible print.

33. Powder and Brush
Here, a hinge lifter is used to lift the developed print. Once applied, the print is preserved.

34. Powder and Brush

35. Powder and Brush
The lift needs to be one fluid motion.

36. Powder and Brush

37. Physical Developer
Documents can be washed with maleic acid and placed into the developer (yellow bath).

38. Physical Developer

39. Physical Developer
The sample should be agitated for 5 to 15 minutes, or removed at the best print.

40. Physical Developer
The physical developer produces a dark fingerprint when applied to latent prints.

41. Small Particle
Small particle reagent is sprayed on areas of suspected latent prints. Primarily used for wet surfaces, the reagent dries leaving behind a “powdered” fingerprint.

42. Ninhydrin
Ninhydrin is used on paper products. Purple fingerprints are developed after drying for 36 hours; or heat can be applied to quicker results.

43. Ninhydrin
A household hair dryer produces enough heat. Heat the sample approximately 2-3 minutes.

44. Ninhydrin
Ninhydrin developed latent fingerprints.

45. Cyanoacrylate Wand
The wand is heated by butane. The brass tip contains cyanoacrylate (super glue).

46. Cyanoacrylate
Cyanoacrylate, or “super glue”, hardens fingerprints into white crystalline prints. Vaporization occurs with heat and humidity.

47. Iodine Crystals
Iodine can be fumed at low temperatures. Once vaporous, it develops reddish-brown fingerprints.

48. Iodine Crystals
The specimen is placed into an air-tight container along with iodine crystals.

49. Iodine Crystals
Iodine is supplied in glass ampules.

50. Iodine Crystals
The air-tight container prevents the escape of iodine vapors.

51. Iodine Crystals
Heat from the hand is sufficient to vaporize the crystals. A hair dryer produces quicker results.

52. Iodine Crystals
An iodine fingerprint. Since iodine evaporates quickly, prints should be photographed.

53. Post Mortem Prints
Kits are available for collecting fingerprints from deceased persons.

54. Post Mortem Prints
Each finger is inked with the porelon pad.

55. Post Mortem Prints
The finger is then pressed into the concave scoop which holds the print card.

56. Post Mortem Prints
All deceased persons should be printed. Once buried or cremated, prints are no longer available.

57. Automated Technology
Computer programs can now match finger-prints. The latent print (left) is matched to the record print (right).

58. Record Fingerprints
Ten-print fingerprint card.

59. Major Case Prints
Major case prints represent all friction ridge surfaces of the fingers and palm.

60. Major Case Prints
Right palm with both outer blades of the hand. Palms are rolled.