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

What creates the unique striations found on bullets fired through a rifled barrel?

Answer: The lands and grooves of rifling in the barrel

Rifling imparts spiral lands and grooves onto the bullet surface, creating individual marks unique to that specific barrel.

What does IBIS stand for in the context of firearms examination?

Answer: Integrated Ballistics Identification System

IBIS is a database that stores and compares digital images of ballistic evidence to link firearms and cartridge cases across multiple cases.

What type of individual evidence is a spent cartridge case recovered at a shooting scene?

Answer: Individual evidence that can be matched to a specific firearm

A fired cartridge case bears unique tool marks from the firearm's firing pin, breech face, extractor, and ejector.

When packaging a firearm as evidence, what is the mandatory first step?

Answer: Unload the weapon and document its condition

Officer safety requires unloading the weapon first, followed by thorough documentation of its condition and position.

Why would a forensic examiner test-fire a recovered firearm in the laboratory?

Answer: To generate reference bullets and cartridge cases for comparison to crime scene evidence

Test-fired specimens provide known samples that can be compared microscopically to ballistic evidence recovered at crime scenes.

What does the term 'caliber' describe when referring to a firearm?

Answer: The internal diameter of the barrel corresponding to ammunition size

Caliber describes the bore diameter of a firearm barrel and directly corresponds to the size of ammunition it chambers.