Forensics Lecture/Ch. 6

Comparison

Eyes adjust to image depending on movement

Dactyloscopy

• Fingerprint identification

• Friction Ridge identification/individualization

• Based on the fact that most tangible things are completely different

Mechanic Of Individualization

• Class Identification

• Individualization

What is under Class identification?

• Fibers

• Hairs

• Paint

What is under Individualization?

• Ridge Detail

• DNA

Class Identification

Grouped or categorize according to common elements or “class characteristics”

Individualization

Examine the object for characteristics or detail specifics to that object

What are the principles of Individualization?

1. Finding agreement of Individual characteristics

2. Having such number and significance

3. That precludes the possibility (or probability)

4. OR their having occurred by mere coincidence

5. Establishing that there are no unexplainable differences

What is fingerprint identification?

How fingerprints are identified

What is ridge minutiae?

• Distinguishable quality in fingerprint used for comparison

• Usually has types including (ending ridge, bifurcation dot)

What is an unusual ridge formation?

Lack of ridge formation; open field

What is GL’s Trike?

Trifurcation

What does the decision making process include/the scientific model stand for?

ACE-V

• Analysis

• Comparison

• Evaluation

• Verification

What does analysis do?

Collect data

What does comparison do?

Test/experiment

What does evaluation do?

Research a conclusion/determination

What does verification do?

Peer review

What are things you can analyze?

• Fingerprint

• Palm Print

• Joint

• Footprint

• Toe Print

What are the levels to analyzing?

1. friction ridge flow, pattern type & general morphological information

2. Individual friction ridge path and associated events, including minutiae

3. Frication ridge dimension attributes, such as width, edge shapes and pores

What happens during the evaluation process?

• A decision (conclusion) is made about the comparison

What are the four decisions that can be made during the evaluation process?

• Individualization

• Exclusion

• Inconclusive (agree to disagree)

• No value (not enough, not keeping)

What happens during the verification process?

• Independent analysis, comparison and evaluation using the ACE process

• “Required” step in the scientific process (peer review)

Define: Dissimilarity

An explainable difference (distortion or damage)

Define: Discrepancy

Unexplainable difference