CJ386-Unit 4 Review• Fingerprints are a means of personal identification• No two fingerprints have ever found to be identical• Class characteristics-basic fingerprint patterns

(loops, whorls, arches)• Individual characteristics (Level II details-

bufurcation, ending ridge, dot and level III details- ridgeosopy and poroscopy)

• Fingerprints develop during fetal development• Fingerprints provide us the ability to grip to

eliminate slippage while grasping objects• A 1:1 photograph with scale should always be taken

of a developed fingerprint

Unit 6–Chapter 15 Seminar Questions

• What is produced in a gun barrel when the barrel undergoes a process known as rifling?

• What is the purpose of rifling gun barrels?

• What does the caliber of a firearm denote?

Unit 6- chapter 15 Questions

• Are the markings or striations on bullets fired from each pistol or rife with rifled barrels unique to that particular weapon?

• Are their any rifles that do not contain rifling characteristics?

• What type of rifle has a smooth bore barrel?

Unit 6-chapter 15 Questions

• What is the difference between a cartridge, a cartridge case and a bullet?

• What instrument is used to examine and compare bullets or cartridge cases?

• What is IBIS and how can it help solve firearms related crimes?

Unit 6 chapter 15 Questions

•  How does the firearms examiner test fire a weapon to obtain bullet and/or cartridge case standards?

•  In gunshot residue analysis, what is a primer and what does it contain?

• What methods are used in the crime lab to identify gunshot primer residue (GSR) from hands?

Unit 6 chapter 15 Questions• When collecting bullets and cartridge cases,

where should you mark the evidence? See pages

• Briefly describe the procedures that must be followed to obtain good quality photographs of footwear impressions.

• Name some other types of impression evidence.

Unit 6-Review

• Grooves are rifled into the bore of firearms to impart spin and accuracy

• Fired bullets and discharged cartridge cases are compare using the comparison microscope

• Identifying characteristics are imparted onto cartridge cases by the breechblock, firing pin, extractor and ejector mechanism

• Gunpowder patterns can be detected by the Greiss chemical test and by infrared photography

• GSR is generally not collected from the hands of suspects more than 6 hours after a shooting incident