Fingerprint Images Forensics Mr. Foster

LOOP WHORL ARCH

Calculating Primary Henry Classification Each Finger is given a point value

Calculate your Primary Henry Classification Assign the number of points for each finger that has a whorl and substitute into the equation: right right left left left index ring thumb middle little + 1 right right right left left thumb middle little index ring + 1 = 16 + 8 + 4 + 2 + 1 16 + 8 + 4 + 2 + 1 Only add the number if you have a whorl on the finger!

Frequency of Fingerprint Patterns Secondary Henry Classification Loops 65% Whorls 30% Arches 5%

There are more than 3 pattern classifications. Right hand Ulnar Right hand Radial

thumb side Pinky side

Frequency of Fingerprint Patterns Secondary Henry Classification Loops 65% Whorls 30% Arches 5% Ulnar Radial Plain Other Tented 60% 20% 10% 4% 1% More specific %’s for categories of each pattern type

Fingerprint Lab and Probability Secondary Henry Classification 2. What would happen to your probabilities if you incorporated the more specific %’s?

Minutiae Or Triradius

Activity #2 Identify 1-15

Activity #3- look at the handout and identify prints that came from the same finger.

KEY

Key to Fingerprint Matching Worksheet A = G = S This one is interesting; there are three separate impressions of the same finger with some very unique features. B = no match C = no match D = no match E = T F = J H = R I = no match K = O L = no match M = P N = Q