INTRODUCTION TO FINGERPRINTING INTRO TO FINGERPRINTING Classification Authors: Veon and O’Boyle 2007 1

INTRO TO FINGERPRINTING LOOP LOOPS Comes in Recurves Goes back out same side Usually curving around a delta INTRO TO FINGERPRINTING 2

INTRO TO FINGERPRINTING ARCH ARCH In one side Rises Falls Goes out the other side INTRO TO FINGERPRINTING 3

INTRO TO FINGERPRINTING WHORL WHORL Ridge recurves around 2 deltas INTRO TO FINGERPRINTING 4

In Depth Classifying 8-TYPES Looking in depth, there are really 8 basic patterns. INTRO TO FINGERPRINTING 5

INTRO TO FINGERPRINTING LOOP-the ridges flow inward and then recurve in the direction of the origin. --A single delta type divergence must be present in front of the recurving ridges Radial Loop-Ridges flow from the recurve toward the radius or thumb side of the hand (approximately 5% of all fingerprint patterns) Ulnar Loop-Friction ridges flow from and recurve toward the ulna or little finger side of the hand, (Approximately 60% of all fingerprint patterns)“PU” LOOP-In Depth INTRO TO FINGERPRINTING Radial Loop Ulnar Loop 6

INTRO TO FINGERPRINTING ARCH-In Depth ARCH-Ridges enter on one side of the impression and tend to flow out the other side with a rise in the center Plain Arch-Ridges enter, wave or rise and exit smoothly INTRO TO FINGERPRINTING Plain Arch Tented Arch-Ridges in the center thrust upward to give an appearance similar to a tent. Inside angle is smaller than 90 degrees Both types of arches comprise about 6% of all fingerprint patterns Tented Arch 7

INTRO TO FINGERPRINTING WHORL-In Depth WHORL-At least two delta type divergences are present with recurving ridges in front of each. (whorls comprise approximately 29% of all fingerprint patterns) Plain Whorl-One or more ridges form a complete revolution around the center (2 deltas) INTRO TO FINGERPRINTING Plain Whorl Central Pocket Loop Whorl- Some ridges form a loop pattern which recurves and surrounds a central whorl (1 delta) Central Pocket Loop Whorl 8

INTRO TO FINGERPRINTING Additional Types Double Loop-Two separate loops are present, which sometimes surround each other. Sometimes called Double Loop Whorl (ying / yang) INTRO TO FINGERPRINTING Double Loop Accidental-Any pattern which does not conform to any of the previous patterns Accidental 9

FINGERPRINT INDIVIDUALIZATION BEYOND THE PATTERN BEYOND THE PATTERN FINGERPRINT INDIVIDUALIZATION

BEYOND THE PATTERN RIDGE ENDING BIFURCATION DOT or ISLAND LAKE or ENCLOSURE INDEPENDENT RIDGE SPUR BRIDGE or CROSSOVER 11

BIFURCATION BEYOND THE PATTERN 12

SPUR BEYOND THE PATTERN 13

RIDGE ENDING BEYOND THE PATTERN 14

BRIDGE or CROSSOVER BEYOND THE PATTERN 15

LAKE or ENCLOSURE BEYOND THE PATTERN 16

DOT or ISLAND BEYOND THE PATTERN INDEPENDENT RIDGE 17

What next... BEYOND THE PATTERN Just the presence of these minutia does not individualize a print It is the exact type of minutia as well as the minutia location that individualizes a print NO TWO PRINTS HAVE EVER BEEN FOUND TO HAVE THE SAME MINUTIA IN THE SAME PLACE Therefore, you can conclude if you are comparing two prints, and they do have the same markings in the same place you must be looking at the same print BEYOND THE PATTERN 18

So how many correlations prove a match? It was in 1918 when Edmond Locard wrote that if 12 points (Galton's Details) were the same between two fingerprints, it would suffice as a positive identification. This is where the often quoted (12 points) originated. Be aware though, there is "NO" required number of points necessary for an identification. Some countries have set their own standards which do include a minimum number of points, but not in the United States. Most agencies intentionally vary the number of correlations to avoid a standard or pattern BEYOND THE PATTERN 19