Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Forensic Science > EXAM study guide > Flashcards

EXAM study guide Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

What is the fire triangle ?

A

Heat
Oxygen
Fuel

When combined together, cause a chain reaction that results in a fire

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the main components of the fire triangle?

A

Fuels
Oxidizers
Ignition sources

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How many components are necessary for a fire to occur?

A

ALL THREE components?????

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Definition: Fire

A

A rapid, self-sustaining oxidation process usually accompanied by the evolution of heat and light in varying intensities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Definition: Explosion

A

The rapid increase in volume and release of energy in an extreme manner; the result, not the cause, of a rapid expansion of gases

It may occur from physical or mechanical change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Definition: Arson

A

A fire set intentionally and maliciously to destroy property or buildings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Definition: Accelerant

A

A substance used to aid the spread of a fire

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Definition: Charring (alligatoring)

A

Checking of charred wood that gives it the appearance of alligator skin

Large rolling blisters indicate rapid, intense heat

Small flat alligatoring indicates slow, less intense heat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Definition: Spalling

A

Flaking or chipping of concrete
Rise in internal pressure due to evaporation
Internal cracking and thermal expansion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Definition: Crazing

A

Formation of small, irregular cracks in glass due to rapid, intense heat, possibly caused by an accelerant

May result from the application of water to the hot glass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Definition: Point of origin

A

Established by:
Area of deepest char
Alligatoring
Usually, the area with the greatest destruction
Identify and eliminate probable accidental ignition sources

** More than one point of origin generally indicates arson!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Definition: Point of demarcation

A
  • Boundary between charred and uncharred material

Puddle shaped line of demarcation on floors or rugs may indicate the use of a liquid accelerant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Definition: Incendiary fire

A

A fire set intentionally by human activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the four classes of fires and how are they defined?

A

Class A
Class B
Class C
Class D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the five classifications that can be assigned during the investigation of a fire event?

A

Natural
Accidental
Criminal (arson)
Suspicious
Unknown origin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Fires are always assumed to be of ______ or ______ origin until proven otherwise

A

NATURAL or ACCIDENTAL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Define each classification of a fire event in the context of an investigation

A

Natural:
Caused by natural events such as lightning, earthquake, wind, etc.

Accidental:
Caused by an accident

Arson:
A fire set intentionally and maliciously to destroy property or buildings

Suspicious:
A fire suspected as arson even though proof is lacking

Unknown origin:
Fire of unknown cause

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Difference between arson and aggravated arson

A

Arson alone is the intentional destruction of a property by fire while aggravated arson is a fire that creates an imminent danger to life or great bodily harm in which risk was known or reasonably foreseeable to the actor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are different kinds of common accelerants and how are they different?

A

Gasoline: petroleum derivative; used mainly as fuel in internal combustion engines

Kerosene: clear liquid hydrocarbon derivative, used as heating and cooking fuel; lamp and lantern oil

Turpentine: Liquid distillate, derived from tree resin, used mainly as a solvent

Fuel oil: Petroleum distillate, used for heating and fuel (diesel)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are common motives for arson?

A

Crime concealment
Revenge or spite
Monetary gain
Malicious vandalism
Extremism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Demographic of arson offenders

A

White males
Almost half under 18 years of age
Many come from broken or unstable homes
Extensive criminal record
Below average intelligence
Lacks marital ties
Socially maladjusted or loner
Unemployed or unskilled employment
Alcohol plays a major role
Self-destructive
Mentally defective
Older
Lonely and unhappy
Possible psychotic problems
Possible schizophrenia

*Female arsonists usually burn their own property; rarely that of an employer, neighbor, or associate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are examples of evidence that investigators look for as signs of arson?

A

More than one point of origin
Deviation from normal burn pattern
Evidence of “trailers”
Evidence of being accelerated
Indicators of abnormal amounts of air, fuel, or heat
Evidence of incendiary igniters at point of origin
Odors or smoke inconsistent with items present at scene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How can you distinguish between accidental and non-accidental fires?

A

Accidental:
Heating system
Electrical appliances
Lightning
Children playing with matches
Smoking

Non-accidental:
Odors
Furnishing
Clothing
Locked windows/blocked doors
Two or more points of origin
Inverted “V” patterns
Floor charred
Trailers

24
Q

Define and know the differences of high vs. low explosives

A

Low explosives are normally used as propellants, including fun powders and pyrotechnics such as smoke bombs, rockets, and illumination devices

High explosives are normally used in demolition and military warheads; high explosive compounds detonate at rates ranging from 3,000 and 9,000 meters per second (examples include, dynamite, cordite, ballistite, and C4)

25
Q

What are the factors that contribute to car crashes?

A

Mechanical failure
Roadway design
Poor road maintenance
Driver behavior

26
Q

What are the 5 common types of mechanical failures that may lead to vehicle accidents?

A

Tires
Brakes
Steering
Suspension
Miscellaneous

27
Q

What are driver behaviors that can lead to a motor vehicle accident?

A

Distracted driving
Speeding
Tailgating
Cutting others off
Not using turn signals
Merging improperly
Not checking blind spots
Driving under the influence
Accelerating through yellow lights
Not driving according to conditions

28
Q

Methods of diagramming an accident scene

A

Triangulation method:
~ Best for unpaved roads, sharp curves, and irregular intersections
~ 2 fixed base points; all measurements made from here (should be widely spaced; wide angles = less error)

Coordinate method:
~ Best for roads with well defined edges and when measurements are within 25ft (7-8m) of edge (road edge is first coordinate/zero/reference point)

29
Q

What factors are considered when determining a vehicle’s speed?

A

Skid distance
Drag factor
Road surface
Braking efficiency

30
Q

What kind of brakes are on the front and back of a motor vehicle?

A

Front: Disc brakes; pressure pushes the pads together which go against the rotor

Back: Drum brakes; pushing brake shoes against the brake drum, wheel studs are attached to the drum

31
Q

What are the cycles of a twin-tube shock absorber?

A

Two cycles with suspension and struts (compression and extension cycle)

32
Q

Types of fuel?

A

gas, plastic, propane

33
Q

What type of steering is common in SUVs, passenger vehicles, and small trucks?

A

Rack and Pinion Steering

34
Q

Tire inflation

A

Tire failure is caused by:
Damaged
Deteriorated
Overinflated
Underinflated
Age

35
Q

Be able to identify the structures on a tire (labeling)

A
  1. Tire size designation
  2. Exterior sidewall on asymmetric tires
  3. Load pressure information
  4. Brand name
  5. Tire construction details
  6. Approval markers (foreign origin tires)
  7. Load capacity index
  8. Speed category symbol
  9. Country of manufacture
  10. Commercial name and identity
  11. Location of tread wear indicators
36
Q

What 2 tools should you keep in your car at all times?

A

Tire pressure and tread depth gauge

37
Q

Who is Albert S. Osborn?

A

✓ 1858-1946
✓ Considered the father of Questioned Document Examination
✓ Widely accepted because of his extensive use of scientific techniques

38
Q

What was Albert S. Osborn known for and what were his major contributions to science?

A

Author of questioned documents book

❑ Albert Osborn and the Lindbergh Baby Case
▪ Provided crucial testimony in the Bruno Hauptmann trial
▪ As a result of his work and national attention, the questioned document field was included in many Federal and State agencies
❑ Albert Osborn was the first President of the American Society of Questioned Document Examiners
▪ He held the position for four years.
▪ The group became a formal association in 1942.

39
Q

What is a questioned document?

A
  • A questioned document is one in which a document in its entirety, or in part, is subject to question as to authenticity and/or origin
  • Any signature, handwriting, typewriting or other marks, whose source or authenticity is in dispute or is doubtful
40
Q

Provide examples of questioned documents?

A

Letters
Voter registration
Checks
Passports
Drivers Licenses
Petitions
Contracts
Threatening Letters
Wills
Suicide Notes
Lottery Tickets

41
Q

What is the difference between a document and a questioned document?

A

Questioned documents are any documents that may be disputed based on source or authenticity

42
Q

What is a forensic document examiner?

A

A person who performs critical examinations on disputed documents in order to establish genuineness or expose forgery

43
Q

What are the qualifications needed to become a forensic document examiner?

A
  • Training programs
  • ProficiencyTests
  • Peer Reviews
  • Professional Organizations
  • Continuing Education
  • Lectures
  • Court Testimony
44
Q

What are the characteristics of handwriting that are useful to forensic document examiners?

A
  • Comparing “questioned” and “known” handwriting, typewriting, commercial printing, and other machine or mechanical impressions.
  • Analyzing paper and ink.
  • Restoring eradicated and obliterated
    impressions.
  • Visualizing indented handwriting impressions.
  • Detecting altered and counterfeit impressions.?????????????????????????
45
Q

What are the subconscious components of handwriting?

A

Letter connections (or lack thereof)
Direction of stroke
Pen lifts or stops
Approach and ending strokes
Proportions

46
Q

Kinds of signatures in handwriting?

A

Slant
Size
Speed
Connecting strokes between letters/words
Spacing between letters/words/lines
Letter forms
“I” dot “T” crossing

47
Q

Define Graphology

A

The study of handwriting to reveal character traits of the writer

✓Sex
✓Writing hand
✓Education
✓Race
✓Character
✓Age
✓Physical ability or disability

Profiles a character or personality by drawing conclusions from certain types of characteristics in the handwriting sample:
* They do not compare handwriting to determine authenticity or origin.
* Most of graphology lacks scientific proof.
* However, some of the principles of graphology are correct, such as:
- Handwriting can be affected by illness, age, etc.

48
Q

Define photomicrography

A

Digital image taken through a microscope to show a magnified image of an item

49
Q

What is “ACE”?

A

Analysis
Comparison
Evaluation

50
Q

What is the difference between a questioned document examiner and a graphologist?

A

Graphologists analyze an individual’s personality through their handwriting alone

Forensic document examiners are highly skilled individuals who cover both handwriting analysis and the full aspects of document examination: determining the printing process, obliterated writing, indentations and much more

51
Q

What landmark case brought Forensic Document Examination into state and federal agencies?

A

The Dreyfus Case (1894): A setback for the discipline
* Alphonse Bertillon, the inventor of anthropometry, gave testimony against a French army officer, Alfred Dreyfus.
* He was accused of treason through letters found, attempting to sell French secrets to Germany.
* It wasn’t until years later, while Dreyfus was incarcerated, that Bertillon’s mistaken opinion was challenged by well known and established forensic document examiners in England and the United States.
* With new evidence introduced, Dreyfus was finally exonerated of the charges of treason.

52
Q

Scientific method!!!!

A

Observation and ask a question
Form a hypothesis
Test with experiment
Analyze data and formulate report conclusion

53
Q

Class A arson investigation?

A

Ordinary solid combustibles such as paper, wood, cloth, and some plastics

54
Q

Class B arson investigation?

A

Flammable liquids such as alcohol, ether, oil, gasoline, and grease, which are best extinguished by smothering

55
Q

Class C arson investigation?

A

Electrical equipment, appliances, and wiring in which the use or a nonconductive extinguishing agent prevents injury from electrical shock. Don’t use water!

56
Q

Class D arson investigation?

A

Certain flammable metallic substances such as sodium, magnesium, and potassium

57
Q

Juvenile fire setters?

A

Children are victims in 85% of juvenile arsons

Categories:
Curious experimenters (less than 7)
Intentional firesetters (8-12)
Crisis fire setters (13-18)

Forensic Science (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions