CSI CSI - Crime Scene Investigator Firearms and Ballistics Evidence Questions and Answers 2 — Questions and Answers
Question 1: What is the purpose of bullet trajectory analysis at a crime scene?
- To identify the manufacturer of the bullet
- To determine the path the bullet traveled and the probable position of the shooter (Correct answer)
- To calculate the age of the firearm used
- To establish whether a firearm was legally purchased
Correct answer: To determine the path the bullet traveled and the probable position of the shooter
Trajectory analysis uses rods and angle measurements to reconstruct the bullet's path and determine the shooter's probable position.
Question 2: What is a 'contact gunshot wound' characterized by?
- No visible powder stippling or soot
- Soot, searing, muzzle imprinting, and possible stellate tearing (Correct answer)
- A perfectly circular entry wound with no additional markings
- A wound caused by a bullet that ricocheted
Correct answer: Soot, searing, muzzle imprinting, and possible stellate tearing
Contact wounds occur when the barrel is pressed directly against skin, causing hot gases and combustion byproducts to enter the wound channel.
Question 3: What does stippling or tattooing around a gunshot wound indicate about firing distance?
- The wound was self-inflicted
- The wound is an exit wound
- The muzzle was at intermediate range when the weapon was fired (Correct answer)
- The bullet was a hollow-point projectile
Correct answer: The muzzle was at intermediate range when the weapon was fired
Stippling is caused by unburned powder particles embedding in skin, which only occurs when the barrel is within intermediate range.
Question 4: What does examining lands and grooves on a fired bullet reveal to a forensic examiner?
- The velocity at which the bullet traveled
- Rifling class characteristics and individual marks unique to the firing barrel (Correct answer)
- The chemical composition of the bullet's copper jacket
- The age of the firearm that fired it
Correct answer: Rifling class characteristics and individual marks unique to the firing barrel
Lands and grooves provide class characteristics such as caliber and twist rate, as well as individual marks unique to a specific barrel.
Question 5: What is the correct method for recovering a fired bullet from a wall to preserve ballistic evidence?
- Metal forceps gripped firmly around the bullet
- Rubber-tipped forceps or by carefully cutting out the surrounding material (Correct answer)
- Standard pliers to extract the bullet quickly
- A vacuum collection system applied to the hole
Correct answer: Rubber-tipped forceps or by carefully cutting out the surrounding material
Rubber-tipped tools or removing surrounding material prevents adding new marks that could interfere with subsequent microscopic comparison.
Question 6: What markings on a cartridge case primer are significant to a firearms examiner?
- The chemical composition of the primer compound
- Firing pin impressions and breech face marks unique to a specific firearm (Correct answer)
- The brand name stamped by the ammunition manufacturer
- The age of the cartridge determined by oxidation
Correct answer: Firing pin impressions and breech face marks unique to a specific firearm
The firing pin strikes and the breech face impress unique microscopic marks onto the primer that can be matched to a specific firearm.
CSI CSI - Crime Scene Investigator Firearms and Ballistics Evidence Questions and Answers 2
What is the purpose of bullet trajectory analysis at a crime scene?