Forensics Ch. 9/10

What is Pre-Analysis?

Pulling print originally before reaching the case file

What does SWGFAST stand for?

Scientific working group on friction ridge analysis, study & technology

What is determined during pre-analysis?

• Suitability

• Sufficiency

• Sufficient

Define: Suitability

The determination that there is sufficiency in an impression to be value for comparison.

Define: Sufficiency

The product quality and quantity of the objective data under observation (friction ridge, creases, scars)

Define: Sufficient

Determination that there is sufficient in a comparison to reach conclusion at the evaluation stage

What is the sufficiency concept/sufficient of friction ridge detail?

• Difficult concept to set standards

• Not consistent among examiners

• Subjective to human variables including: Training, knowledge, ability, experience & talent, motivation, personality

What two things determines sufficiency?

• Quality

• Quantity

What are the three things to determining quality?

1. Contrast: separation of black, white, or colors

2. Sharpness: the legibility of detail present

3. Interference: ability to discern features from artifacts (distortion)

What are the levels of quality?

• High- most clear prints

• Medium High

• Medium Low

• Low- can not see prints

Under aspects of quantity, what are three type of friction ridge features?

• Usual Types- ending ridge, bifurcation, dot

• Unusual Types- rarity dots in a row, trifurcation

• Lack of features- open field

Under aspects of quantity, what are relative positions of friction ridge flow?

• Ridge flow continuity

• Spatial frequency (ridges/furrows)

Three parts to the Sufficiency Graph

• A= not warranted, red

• B= May be warranted, yellow

• C= Warranted, Green

What are the three friction ridge impression categories?

• Sufficient for case evidence

• Sufficient for comparison & sufficient for case evidence

• Sufficient for individualization, comparison & case evidence

Define this Category: Sufficient for case evidence

Using pre-analysis, determine in the friction ridge impression is suitable for case evidence

Define this Category: Sufficient for comparison & sufficient for case evidence

During analysis, determine if the friction ridge impression & tenprint is sufficient for comparison

Define this Category: Sufficient for individualization, comparison & case evidence

During comparison, determine if the friction ridge impression is sufficient for individualization

Define the first step of the ACE-V method?

Assessing an impression to determine sustainability for comparison. Determining if friction ridge is sufficient enough for comparison

Define the second step of the ACE-V method?

Observing two or more impressions to determine the existence of discrepancies, dissimilarities, or similarities.

Looking between latent and tenprint to see minutiae in agreement or disagreement.

Define the third step of the ACE-V method?

An examiner assess the value of the details observed during analysis and comparison steps; reaches conclusion

What are the three definitions for conclusion?

• Exclusion

• Individualization

• Inconclusive

Define: Exclusion

There is sufficient quality or quantity of detail in disagreement concluding that two areas of friction ridge impressions did not originate from the same source

Define: Individualization

Sufficient quality & quantity of detail in agreement to conclude friction ridge was from the same original source

Define: Inconclusive

Not sufficient agreement to individualize, not to exclude

Define: Peer Review

Used to determine clerical accuracy of reports & case documentation & ensure the examiner has followed procedure

Workflow Exam

1. Processing by technician

2. Comparison by LPE: Processes evidence with powders/chemicals

3. Verification by LPE

What does AFIS stand for & what does it contain?

Automated Fingerprint Identification System

• fingerprints

What does ABIS stand for & what does it contain?

Automated Biometric Identification System

• fingerprints

• palm prints

• mugshots

• iris scans

What is Verification for?

To ensure their is sufficiency of a friction ridge impression measure