1. 90+% of the information in this presentation was taken directly from
Fingerprints
90+% of the information in this presentation was taken directly from

2. Ancient History is a mystery
Suggested that thumbprints on Babylonian clay tablets and ancient Chinese clay seals were deliberately placed there as identifying marks

3. Sir Francis Galton Established that fingerprints are unique.
Wrote book Fingerprints
This introduced modern techniques of criminal investigation, replacing tatooting, branding, and body measurements as methods of identifying criminals.
(Charles Darwin’s Cousin)

4. Galton’s Premises(or Galton Details)
First to categorize minutia and observe that they remain unchanged.
Uniqueness
All Fingerprints are different
Nature does not repeat any object in complete detail.
Permanence
Fingerprint patterns remain constant as a person matures.
Superficial skin damage grows back to original
Severe cuts and resulting scars remain permanent.

5. Sir Edward Richard Henry
Developed a method of indexing fingerprints = Henry Classification System.
Problem: need all 10 prints
Book: Classification and Uses of Fingerprints
Classifies fingerprints into three types: Arches, Loops, and Whorls

6. Johannes Purkinje
In his doctoral thesis, he identified nine print patterns:
Arch
Tented arch
Loop
Six Whorls

9. The basic tenets of friction skin identification are: Friction skin is UNIQUE Friction skin develops before birth, is PERMANENT and NEVER CHANGES Variation in ridge patterns vary within specific limits and can be classified.

10. ACE-V Analysis Comparison Evaluation Verification accepted method
The generally
accepted method
for friction ridge
individualization

11. RIDGE Detail
1st Level Detail
2nd Level Detail
3rd Level Detail

14. Where to look for minutiae
The area immediately surrounding a delta will probably contain more points per square millimeter than the area near the tip of the finger which tends to not have that many points.

15. Finding Minutiae
These are only 10 of the 22 in this ¼ X ¼ inch section.

16. Finding Minutiae May not be all that easy. In real life, impressions
are made at separate times.
are subject to different pressure distortions.
from a crime scene are anything but clear.
from a crime scene could be a fingertip, palm or even foot impression, not the core of a fingerprint.

17. Classification
Ya gotta be able to find the delta(s) or recognize a lack of them!
Deltas =
a place where two lines run side-by-side and then diverge with a significant recurving line that passes in front of the delta.

18. Classification Based on Deltas
If the print has one delta then the pattern is a loop.
If the pattern has more than 1 delta then it is a whorl.
If the pattern has no delta's then it is an arch.
Simple enough so long as you can effectively identify the deltas.

19. Classification: Loops (65%)
Loops only have one delta.
They also have one core.
Core
Delta

20. Arm Bones
Radius – on thumb side; thick near wrist
Ulna

21. Ulnar and Radial Loops
If on left hand, comes in and goes out from pinky side = ulnar side =
ulnar loop
If on right hand, comes in and goes out from thumb side =
radial side =
radial loop

22. Plain Arch
No delta
No significant core

23. Tented Arch Has a "significant upthrust"
No, that’s not a delta. To be a valid delta there has to be a significant recurving line that passes in front of the delta

24. Plain Whorl Must be more than one delta
Must intersect lines that make up the whorl when you draw a straight line between the deltas.

25. Are these plain whorls?

26. Central Pocket Whorl
The ridges that form the inner pattern of the whorl are not crossed by an imaginary line drawn between the two deltas.

27. Accidental Whorl
Is a pattern not covered by other categories, or is a combination (e.g., loop and plain whorl or loop and tented arch).

28. Double Loop Whorl
Has two separate and distinct loop formations with two separate and distinct shoulders and two deltas

29. Double Loop Whorl
The shoulders of each "core" must comprise separate lines.

30. Double Loop Whorl
The shoulders of each "core" must comprise separate lines.
Here they don’t.