Fingerprints and Exhibits

Question 1

What is a fingerprint?

Answer 1

An impression of the friction ridges of all or any part of the finger.

Question 2

What are the two types of human friction ridge skin?

Answer 2

• Palmar – bottom of hands
• Plantar – bottom of feet

Question 3

What is the uniqueness of human friction ridge skin?

Answer 3

Each individual possesses a unique arrangement of friction skin; no two fingerprints are the same.

Question 4

How persistent is human friction ridge skin throughout a person’s lifetime?

Answer 4

The sequence of the ridges and the arrangement of the minutiae do not change, except for injury.

Question 5

At what stage of development are fingerprints fully formed?

Answer 5

By the time a fetus is 6 months old.

Question 6

What percentage of a deposited fingerprint is composed of water?

Answer 6

Almost 99%.

Question 7

List the functions of skin.

Answer 7

• Acts as a container for the skeletal structure and internal organs
• Provides sensory input about external conditions
• Eliminates waste products through sweating
• Allows for the ability to grasp surfaces firmly

Question 8

What are the two distinct layers of friction ridge skin?

Answer 8

• Epidermis (top)
• Dermis (bottom)

Question 9

What is the generating layer of the epidermis?

Answer 9

The bottom layer of the epidermis adjacent to the dermis where new cells are formed.

Question 10

What are the three levels of detail in examining fingerprints?

Answer 10

• Level 1 - Pattern
• Level 2 – Ridge Characteristics
• Level 3 – Pores, Ridge Edges

Question 11

What are the three basic fingerprint patterns?

Answer 11

• Loop
• Whorl
• Arch

Question 12

What is the average number of ridge characteristics in a finger?

Answer 12

As many as 150 ridge characteristics.

Question 13

What is an incipient ridge?

Answer 13

Friction ridges that did not fully form; may appear shorter and thinner.

Question 14

What does the ACE-V method stand for?

Answer 14

• Analysis
• Comparison
• Evaluation
• Verification

Question 15

What is the purpose of the analysis step in the ACE-V method?

Answer 15

To assess an unknown impression to determine suitability for comparison.

Question 16

What is the evaluation step in the ACE-V method?

Answer 16

An examiner assesses the value of the details observed and reaches a conclusion.

Question 17

What are the possible conclusions in the evaluation step?

Answer 17

• Identification/individualization: from the same source
• Exclusion: not from the same source
• Inconclusive: unable to identify or exclude

Question 18

What are the types of fingerprint impressions found at crime scenes?

Answer 18

• Latent – not visible to the naked eye
• Visible – readily visible
• Moulded – retains 3D shape

Question 19

What is the primary method used for making latent prints visible on nonporous surfaces?

Answer 19

Powdering.

Question 20

What is the correct technique for powdering a fingerprint?

Answer 20

Brush in the direction of any ridges that begin to appear and build powder onto ridges.

Question 21

What should be included when marking a fingerprint?

Answer 21

• Circle around the print
• Use letters and numbers sequentially
• Date and initials
• Scale close to the print

Question 22

What is the purpose of photographing a fingerprint?

Answer 22

To document the print with overall, mid-range, and close-up photos.

Question 23

What is the purpose of a lift card in fingerprinting?

Answer 23

To document the details of the lifted fingerprint.

Question 24

What are the packaging requirements for exhibits in fingerprinting?

Answer 24

• New unused packaging
• Avoid contamination
• Secure transport

Question 25

What is the importance of wearing PPE when collecting exhibits?

Answer 25

To avoid contamination of the exhibits.

Question 26

True or False: The conclusion reached in fingerprint analysis is always objective.

Answer 26

False.