UTA CSI FINAL EXAM QUESTIONS
AND ANSWERS
Rubber Casting Compounds: - ANSWER-• Used for impressions (toolmarks, etc.) on
nearly any surface.
• Special silicone materials capture microscopic details.
• If possible, recover the actual impression as well.
Trajectory Analysis: - ANSWER-· Trajectory analysis involves three areas of related
ballistic study. These are:
o Interior or internal ballistics
o Terminal ballistics.
o Exterior or external ballistics.
· Each area of study is accomplished by different parties, but all are necessary to
understand the scene.
Internal Ballistics: - ANSWER-· Conducted by the forensic firearms examiner at the
crime lab.
· Involves function and operation of the weapon, association of weapon, bullets and
cartridge cases.
· Often involves evaluation of ejection patterns and gunshot residue range (distance)
determinations.
Wound Ballistics (Sometimes referred to Terminal Ballistics): - ANSWER-·
Conducted by the forensic pathologist.
· Involves defining the path of a bullet through the body, the associated damage and
differentiating entry from exit wounds.
Also includes issues of range (distance) determinations
Range (Distance) Determinations: - ANSWER-· Forensic firearm examiners use the
weapon and similar ammunition to create gun powder residue standards at different
distances. These are then compared to the questioned residue patterns.
· The forensic pathologist defines approximate range by evaluating physical
characteristics of the wound. The ranges include:
o Close contact - pressed to the skin.
o Loose contact - close proximity to the skin, small gap.
o Near Contact - not more than five inches from the wound.
o Intermediate Range - 5 - 40 inches from the wound.
o Indeterminate Range - no characteristics, so no conclusion.
· Other forensic pathologists as well as forensic firearm examiners can have systems
or terms that differ somewhat from those of the author of our text. When referring to
gunshot range distances in a report or during a testimony, you always need to make
sure that you know to what distance the author or expert is referring.
External Ballistics: - ANSWER-· Conducted by the crime scene analyst most often,
may involve the firearms examiner.
, · Involves defining the path of a bullet through the scene by evaluating various
scenes aspects, such as penetrations and perforations, cartridge cases and known
positions of the victim or shooter.
· Ultimately it defines possible and impossible scenarios for bullet trajectories.
Bullet Defect Characteristics: - ANSWER-· Entry bullet defects generally have a
symmetrical circular or elliptical aspect.
· Exit bullet defects generally have an irregular or asymmetrical shape. Material
pushed out from the defect will suggest exit (e.g. showing the direction of travel of
the bullet.)
· Concerns:
o Deflections or Ricochet:
ü When the bullet strikes a surface and deflects off it at some angle without
penetrating the surface completely
ü The bullet itself may show indications of the angle at which it deflected
o Tumbling: Tumbling bullets often create distinct characteristics.
ü Obvious tumbling eliminates any ability to evaluate impact angle.
Prepare Impression: - ANSWER-1. Place an L-shaped or long straight flat ruler
alongside the length of the impression. If it is a three-dimensional impression,
carefully position the ruler on the same plane (level) as the bottom of the impression.
Include a label on the ruler to link this impression to the identifier number used in the
general crime scene photographs and notes, as well as in subsequent casts or lifts.
Use Oblique Lighting: - ANSWER-Oblique lighting should be used in most instances
for both two-dimensional and three-dimensional impressions
CASTING: - ANSWER-The filling of a three-dimensional footwear or tire tread
impression with a material that will take on and retain the characteristics left in that
impression.
"Photography and casting supplement one another to give the maximum amount of
information about an impression to the examiner." William J. Bodziak
Casting: - ANSWER-• Gives life-like and actual-size molding of the original
impression including uneven surfaces and depths
• Gives reproduction of microscopic characteristics
• In deep impressions, gives reproduction of characteristics of the sides of outsoles
and midsoles of the shoes which are usually not reproduced in photographs
• Never a focus or scale problem
• Provides tangible 3-dimensional evidence
• Backs up photography
Casting Materials Requirements: - ANSWER-1. Capable of reproducing very fine
detail.
2. A viscosity that will allow even flow into the impression but not be absorbed by it.
3. Able to be cleaned without loss of detail and should release itself from the material
in
which the impression was made.
4. Reasonable in cost.
5. Easily obtainable in a consistent form and quality.
AND ANSWERS
Rubber Casting Compounds: - ANSWER-• Used for impressions (toolmarks, etc.) on
nearly any surface.
• Special silicone materials capture microscopic details.
• If possible, recover the actual impression as well.
Trajectory Analysis: - ANSWER-· Trajectory analysis involves three areas of related
ballistic study. These are:
o Interior or internal ballistics
o Terminal ballistics.
o Exterior or external ballistics.
· Each area of study is accomplished by different parties, but all are necessary to
understand the scene.
Internal Ballistics: - ANSWER-· Conducted by the forensic firearms examiner at the
crime lab.
· Involves function and operation of the weapon, association of weapon, bullets and
cartridge cases.
· Often involves evaluation of ejection patterns and gunshot residue range (distance)
determinations.
Wound Ballistics (Sometimes referred to Terminal Ballistics): - ANSWER-·
Conducted by the forensic pathologist.
· Involves defining the path of a bullet through the body, the associated damage and
differentiating entry from exit wounds.
Also includes issues of range (distance) determinations
Range (Distance) Determinations: - ANSWER-· Forensic firearm examiners use the
weapon and similar ammunition to create gun powder residue standards at different
distances. These are then compared to the questioned residue patterns.
· The forensic pathologist defines approximate range by evaluating physical
characteristics of the wound. The ranges include:
o Close contact - pressed to the skin.
o Loose contact - close proximity to the skin, small gap.
o Near Contact - not more than five inches from the wound.
o Intermediate Range - 5 - 40 inches from the wound.
o Indeterminate Range - no characteristics, so no conclusion.
· Other forensic pathologists as well as forensic firearm examiners can have systems
or terms that differ somewhat from those of the author of our text. When referring to
gunshot range distances in a report or during a testimony, you always need to make
sure that you know to what distance the author or expert is referring.
External Ballistics: - ANSWER-· Conducted by the crime scene analyst most often,
may involve the firearms examiner.
, · Involves defining the path of a bullet through the scene by evaluating various
scenes aspects, such as penetrations and perforations, cartridge cases and known
positions of the victim or shooter.
· Ultimately it defines possible and impossible scenarios for bullet trajectories.
Bullet Defect Characteristics: - ANSWER-· Entry bullet defects generally have a
symmetrical circular or elliptical aspect.
· Exit bullet defects generally have an irregular or asymmetrical shape. Material
pushed out from the defect will suggest exit (e.g. showing the direction of travel of
the bullet.)
· Concerns:
o Deflections or Ricochet:
ü When the bullet strikes a surface and deflects off it at some angle without
penetrating the surface completely
ü The bullet itself may show indications of the angle at which it deflected
o Tumbling: Tumbling bullets often create distinct characteristics.
ü Obvious tumbling eliminates any ability to evaluate impact angle.
Prepare Impression: - ANSWER-1. Place an L-shaped or long straight flat ruler
alongside the length of the impression. If it is a three-dimensional impression,
carefully position the ruler on the same plane (level) as the bottom of the impression.
Include a label on the ruler to link this impression to the identifier number used in the
general crime scene photographs and notes, as well as in subsequent casts or lifts.
Use Oblique Lighting: - ANSWER-Oblique lighting should be used in most instances
for both two-dimensional and three-dimensional impressions
CASTING: - ANSWER-The filling of a three-dimensional footwear or tire tread
impression with a material that will take on and retain the characteristics left in that
impression.
"Photography and casting supplement one another to give the maximum amount of
information about an impression to the examiner." William J. Bodziak
Casting: - ANSWER-• Gives life-like and actual-size molding of the original
impression including uneven surfaces and depths
• Gives reproduction of microscopic characteristics
• In deep impressions, gives reproduction of characteristics of the sides of outsoles
and midsoles of the shoes which are usually not reproduced in photographs
• Never a focus or scale problem
• Provides tangible 3-dimensional evidence
• Backs up photography
Casting Materials Requirements: - ANSWER-1. Capable of reproducing very fine
detail.
2. A viscosity that will allow even flow into the impression but not be absorbed by it.
3. Able to be cleaned without loss of detail and should release itself from the material
in
which the impression was made.
4. Reasonable in cost.
5. Easily obtainable in a consistent form and quality.
