Chapter 4 - Physical Evidence

Question 1

What are the two kinds of proof used during a criminal trial to answer the questions of guilt or innocence?

Answer 1

direct evidence & circumstantial evidence

Question 2

What kind of evidence involves eyewitnesses who have, through one or more of their five senses, experienced something relative to the crime in question or its circumstances?

Answer 2

direct evidence

Question 3

What type of evidence is defined as evidence from which an inference can be drawn and which includes items such as physical evidence?

Answer 3

circumstantial evidence

Question 4

What are the two broad categories physical evidence can be divided into?

Answer 4

class evidence & individual evidence

Question 5

Glass , paint, shoe prints, ballistics, fibers and tool marks are good examples of what type of evidence?

Answer 5

class evidence

Question 6

Fingerprints are a good example of what type of evidence?

Answer 6

individual evidence

Question 7

Is it possible for class evidence to become individual evidence?

Answer 7

yes

Question 8

What are the primary sources for identification in regard to ballistics?

Answer 8

inside of the barrel, firing pin, breech face, the chamber and ejector/extractor

Question 9

______ is the identification of firearms, bullets, cartridges and shotgun shells

Answer 9

ballistics

Question 10

____ ballistics refers to the functioning of firearms through the firing cycle.

Answer 10

interior

Question 11

____ ballistics is the study of projectiles in flight.

Answer 11

exterior

Question 12

if the caliber is not marked on a firearm the investigator should qualify any estimate of the caliber by putting _______ in his or her field notes and noting a measurement across the bore of the weapon in _____ ____ ___ ___.

Answer 12

unknown, fractions of an inch

Question 13

What test is performed when when you examine adhesive tapes using a scanning electron microscope interfaced with an energy-dispersive x-ray?

Answer 13

gunshot residue examination

Question 14

What type of reaction leads to a rapid increase in temperature followed by a sharp decrease resulting in a unique spheroidal formation that is not generally observed in the natural environment?

Answer 14

exothermic reaction

Question 15

What color do relatively fresh blood stains appear to be?

Answer 15

reddish-brown

Question 16

Over time blood stains can appear to be what colors?

Answer 16

red to black, green, blue or grayish white

Question 17

What test is used to determine whether or not a stain is blood?

Answer 17

the Kastle-Meyer color test

Question 18

During the Kastle-Meyer color test, what color does the test strip turn as it reacts with the enzymes in the blood?

Answer 18

deep pink

Question 19

What are the name of the test strips used for a presumptive field test for blood?

Answer 19

Hemastix

Question 20

What presumptive test could be used to tell whether blood has once been at the crime scene and since been cleaned up?

Answer 20

luminol

Question 21

Luminol does not produce color, instead it produces _____?

Answer 21

light

Question 22

Luminol produces a faint blue glow called what?

Answer 22

luminescence

Question 23

What advantage does Bluestar have over luminol?

Answer 23

bloodstains can be observed without having to create complete darkness

Question 24

BLuestar and luminol are both capable of detecting bloodstains diluted up to _______ times?

Answer 24

100,000

Question 25

What is the final determination needing to be made after you have found and determined a stain to be blood?

Answer 25

Whether it is animal or human

Question 26

What test is used to determine whether blood found is animal or human?

Answer 26

Precipitin test

Question 27

What test takes advantage of the fact that antibodies and antigens diffuse or move toward one another on a plate coated with a gel medium made from a polymer called agar and is also another precipitin test?

Answer 27

Gel diffusion

Question 28

_______ are markings left on a surface by protruding parts of a person or vehicle?

Answer 28

Imprints

Question 29

________ are made by a person or an object in a material softer than the item of evidence

Answer 29

Impressions

Question 30

Fingerprints that are bloody and left on a weapon at the crime scene are called __________ prints.

Answer 30

Contaminated

Question 31

What type of fingerprints can are you able to see with the naked eye?

Answer 31

Plastic prints

Question 32

What type of prints cannot be seen with the naked eye and need to be developed?

Answer 32

Latent prints

Question 33

What process is used to develop latent fingerprints found on a porous surface such as paper?

Answer 33

Iodine fuming or ninhydrin process

Question 34

When developing latent prints with iodine fuming, the fumes react with the amino acids in the print and turn what color?

Answer 34

Purple

Question 35

If a latent print was left on a smooth or slippery surface what process would be used to develop it?

Answer 35

Cyanoacrylate fuming process

Question 36

What does AFIS stand for?

Answer 36

Automated fingerprint identification system

Question 37

What has to be attached to the hair for DNA analysis to be considered?

Answer 37

The root bulb

Question 38

What is the approximate rate of hair growth?

Answer 38

One centimeter per month

Question 39

What two groups are fibers classified into?

Answer 39

Natural and manufactured

Question 40

What are the most common natural fibers?

Answer 40

Cotton and wool

Question 41

What type of microscope is connected together side by side that allows two samples to be viewed simultaneously?

Answer 41

Comparison microscope

Question 42

When beginning to compare two fibers what two features would be compared first?

Answer 42

Color and diameter

Question 43

What are the two types of glass fractures?

Answer 43

Radial and concentric

Question 44

What type of fracture starts at the center and run outward in a star shaped pattern?

Answer 44

Radial

Question 45

What type of fracture forms concentric circular crack in the glass around the point of impact?

Answer 45

Concentric

Question 46

What is more useful a paint chip or smear?

Answer 46

Chip

Question 47

What is the most that can be determined from paint when comparing two samples?

Answer 47

The control and questioned sources are consistent