October 21st Quiz (Fingerprints To Footwear)

Question 1

What kinds of materials make up fingerprints?

Answer 1

Sebaceous oils, amino acids, lipids, other materials.

Question 2

What kinds of things temporarily alter fingerprints? How long do they take to normalize?

Answer 2

Warts, minor injuries, acute skin issues, dermatitis,

30 days.

Question 3

What questions should investigators ask about fingerprints to determine innocent mechanism vs evidentiary value?

Answer 3

When was surface cleaned/touched/etc. Determine timeline.

Question 4

What is a fingerprint matrix?

Answer 4

Basically the stuff that the finger leaves when touching something

Question 5

What is a test impression? (Footwear/tires)

Answer 5

An impression made for comparison purposes

Question 6

Define 3D vs 2D vs transfer impressions

Answer 6

3D: made on something soft, can measure depth (ie soil, sand, snow,)

2D: made on something hard, can’t measure depth (ie floor)

Transfer: impression made by dust/paint/whatever picked up from elsewhere

Question 7

Define class characteristics vs accidental characteristics

Answer 7

Class: shared by 2+ items of footwear/tires (ie if they were from the same manufacturer)

Accidental: holes/tears/etc

Question 8

Define non-association

Answer 8

Not enough detail for exclusion, but impression has dissimilarities to known sample.

Question 9

Limited association

Answer 9

Some similar class characteristics, but no confirmable differences to exclude footwear/tire.

Question 10

Association

Answer 10

Both design and physical size correspond, maybe also similar wear.

Question 11

High association

Answer 11

Correspond in design/physical size/wear. Also 1+ random characteristics or unusual wear shared.

Question 12

What kinds of development mediums are there for fingerprints and what do they do?

Answer 12

Powders and superglue chambers. Target amino acids or use wavelengths of light to determine types of substances in the fingerprint matrix.

Question 13

What are the 7 footwear and tire conclusions?

Answer 13

1. Insufficient detail
2. Exclusion
3. Indications of non-association
4. Limited association of class characteristics
5. Association of class characteristics
6. High degree of association
7. Identification

Question 14

What are the skin layers to know? Think corn, lucid, grain, spine, base, and dermis

Answer 14

Stratum corneum
Stratum lucidum
Stratum granulosum
Stratum spinosum
Stratum basale
Dermis

Question 15

What is FLS and what does it do?

Answer 15

FLS (forensic light source) examines substrates for various substances by using wavelengths in nanometers.

Question 16

What is cyanoacrylate? Another name?

Answer 16

Aka superglue, for non-porous surfaces (ie glass, plastic, etc)

Question 17

What does SWGFAST stand for?

Answer 17

Scientific working group on friction ridge analysts, study and technology

Question 18

What type of fingerprint has ZERO deltas?

Answer 18

Arch, tented arch

Question 19

What type of fingerprint has two deltas?

Answer 19

Whorl

Question 20

Does analyzing FLS require goggles?

Answer 20

Yes

Question 21

What is a development medium that targets amino acids in sweat?

Answer 21

Indanedione Zinc Chloride

Question 22

Who solved the Rojas murders?

Answer 22

Vucetich

Question 23

Another word for fracture characteristics on the outside of treads?

Answer 23

Tears