Forensic Evidence Collection and Analysis

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Questions and Answers

What is defined as an indentation or 'print' made by footwear or fire tread?

Mold characteristic

Impression (correct)

Tear

Test impression

Which characteristic refers to the design and size features of a mold?

Position and orientation of wear

Physical size

Test impression

Mold characteristic (correct)

What describes the way footwear is worn, including its outer part?

Impression

Position and orientation of wear (correct)

Tear

Mold characteristic

Which term refers to a rip found in footwear that is not a design characteristic?

Tear Signup and view all the answers

What is an impression created to compare with another impression obtained at a scene called?

Test impression Signup and view all the answers

What is the primary purpose of the chain of continuity/custody?

To document every point of contact of evidence Signup and view all the answers

Which of the following best describes Locard's principle of exchange?

Objects that come into contact inevitably leave evidence Signup and view all the answers

Inductive reasoning primarily involves moving from which type of ideas to which?

Specific ideas to general explanations Signup and view all the answers

Which of the following is considered a type of physical evidence?

Glass fragments Signup and view all the answers

What can blood, semen, and saliva evidence contribute to an investigation?

Building a DNA profile on a suspect Signup and view all the answers

Which type of evidence can help determine the order of shots in a shooting case?

Glass fragments Signup and view all the answers

What type of evidence does not include mind-altering substances?

Documents Signup and view all the answers

What defines a three-dimensional impression?

An impression with measurements of length, width, and depth. Signup and view all the answers

What role do fingerprints play at a crime scene?

They can be used to identify a suspect Signup and view all the answers

What is a transfer impression?

An impression made on a 2-D surface from foot or tire contact. Signup and view all the answers

Which statement correctly describes a two-dimensional impression?

It consists of measurements of length and width. Signup and view all the answers

What does the term 'wear' refer to?

The damage caused to an object after continued use. Signup and view all the answers

Which of the following is NOT a characteristic of a transfer impression?

It is always visible as a distinct outline. Signup and view all the answers

What is the primary application of Diafluorin-a-one?

To chemically analyze amino acids Signup and view all the answers

What are class characteristics in the context of forensic analysis?

Common traits shared by a group of samples Signup and view all the answers

What does the term 'insufficient detail' refer to in forensic samples?

When a sample cannot produce a positive match Signup and view all the answers

Which reagent is used to determine the presence of blood in fingerprint analysis?

1,2 Indanedione Zinc Chloride Signup and view all the answers

What is meant by 'accidental characteristics'?

Marks acquired through individual circumstances Signup and view all the answers

What role do stabilizing agents play in forensic investigations?

They preserve footprints and tire treads Signup and view all the answers

What does degree of wear refer to in forensic footwear analysis?

The extent of damage to the outsole Signup and view all the answers

Which of the following is NOT a use of dental cement in forensics?

Analyzing chemical composition of samples Signup and view all the answers

What is the definition of a satellite stain?

A stain that originates from a parent stain. Signup and view all the answers

What does the term 'impact stains' refer to?

Stains formed when blood exits the body due to trauma. Signup and view all the answers

Which term refers to the blood pattern that forms an arch shape?

Cast-off pattern Signup and view all the answers

What does a wipe pattern indicate?

Blood left on an object that passed through wet blood. Signup and view all the answers

The term 'parent stain' refers to what?

The original blood stain from which satellite stains are derived. Signup and view all the answers

What does a back spatter pattern describe?

Blood that exits in the opposite direction of an impact. Signup and view all the answers

What is a serum stain?

A stain that results from the separation of blood into its components due to coagulation. Signup and view all the answers

What is indicated by a pool of blood?

Blood that collects in one area due to gravity. Signup and view all the answers

Study Notes

Chain of Custody

A record of every point of contact that each piece of evidence has come into.

Locard's Principle of Exchange

All objects that come into contact with each other leave behind evidence of said contact.

Deductive Reasoning

Narrowing down specific possibilities from general ideas.

Inductive Reasoning

Specific ideas leading to general explanations.

Types of Physical Evidence

Drugs: Any mind-altering substance including alcohol and cannabis.
Explosives: Any object with explosive properties (e.g., detonator).
Documents: Can include information linking a suspect to a crime.
Blood, Semen, Saliva: Substances containing DNA that can build a DNA profile on a suspect.
Glass Fragments: Can be studied to determine the order of shots in cases involving projectiles.
Hair: Human and/or pet hair can be used to link a suspect to a crime scene.
Fingerprints: Fingerprints left at a crime scene can be used to identify a suspect.

Fingerprint Enhancement Techniques

Ninhydrin: Used to chemically absorb amino acids from porous substrates.
1,8 Diafluorin-a-one: Used to chemically absorb amino acids from porous substrates
1,2 Indanedione Zinc Chloride: Used to chemically absorb amino acids from porous substrates.
Blood Reagents: Can be used to test if a fingerprint has blood and if that blood is animal or human.

Footwear/Tire Tread Preservation

Stabilizing agents can be used to preserve footprints and tire treads.
Dental cement can be used to make molds of footprints.

Class Characteristics

Characteristics that one or more samples share in common.
Not enough to create a positive identification.

Accidental Characteristics

Characteristics acquired through individual circumstances.

Footwear/Tire Tread Evidence Examples

Degree of Wear: How damaged a footwear outsole or tire has become.
Insufficient Detail: When a sample lacks enough individual detail to generate a positive match.
Impression: An indentation or "print" made by footwear or tire tread.
Known Footwear or Tire: A sample used to compare to footwear or tire impressions found at a scene.
Mold Characteristic: Design and size features of a mold.
Physical Size: The measurements of a footwear or tire.
Position and Orientation of Wear: The way in which a footwear outsole or tire is worn.
Tears: A rip in a footwear outsole or tire that is not a design characteristic.
Test Impression: An impression created to compare to an impression obtained at a scene.
Three-Dimensional Impression: An impression with measurements of length, width, and depth.
Transfer Impression: A footwear/tire impression made on a 2-D surface when footwear/tire picks up dust, residue, mud, blood, etc.
Two-Dimensional Impression: An impression with measurements of length and width.
Wear: The "damage" done to an object after continued use.

Bloodstain Patterns

Aspiration: Air bubbles in blood.
Flow Pattern: An area of blood moves/settles due to gravity.
Pool: An area of blood that has been collecting in one spot.
Projected Pattern: A pattern left by blood that has been forced out by a projectile.
Satellite Stain: A stain created from a parent stain.
Serum Stain: A stain left by blood that has been separated into its different elements due to coagulation.
Parent Stain: The origin of a satellite stain.
Transfer Stains: When blood is transferred from one surface to another.
Cast-Off Pattern: A blood pattern that arches.
Insect Stain: A stain created due to insect activity.
Swipe Pattern: Transfer of blood from one surface to another.
Wipe Pattern: When an object has run through a wet blood stain.
Impact Stains: A stain created when blood exits the body due to impact.
Back Spatter Pattern: When blood exits the body in the opposite direction of the impact.

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Description

Explore the critical concepts of forensic evidence collection in this quiz, focusing on chain of custody, Locard's Principle of Exchange, and types of physical evidence. Test your knowledge on deductive and inductive reasoning as it applies to crime scene investigations.