CSI - Crime Scene Investigator Firearms and Ballistics Evidence Questions and Answers Flashcards

What is the purpose of bullet trajectory analysis at a crime scene?

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.

What is a 'contact gunshot wound' characterized by?

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.

What does stippling or tattooing around a gunshot wound indicate about firing distance?

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.

What does examining lands and grooves on a fired bullet reveal to a forensic examiner?

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.

What is the correct method for recovering a fired bullet from a wall to preserve ballistic evidence?

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.

What markings on a cartridge case primer are significant to a firearms examiner?

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.