Chapter 10 - Bloodstain Pattern Analysis

Question 1

Violent contact between individuals at a crime scene frequently produces bleeding and results in the formation of _____.

Answer 1

Bloodstain patterns

Question 2

The proper interpretation of bloodstain patterns necessitates carefully planned _____ using surface materials comparable to those found at the crime scene.

Answer 2

control experiments

Question 3

Bloodstain patterns may convey to the analyst the location and movements of _____ or _____ during the commission of a crime.

Answer 3

victims or suspects

Question 4

T or F: Harder and less porous surfaces result in less spatter, whereas rough surfaces result in stains with more spatter and serrated edges.

Answer 4

True

Question 5

Generally, bloodstain diameter will do what with hight?

Answer 5

increase

Question 6

The _____ and _____ of blood striking an object may be discerned by the stain’s shape.

Answer 6

directionality; angle of impact

Question 7

A drop of blood that strikes a surface at an angle of impact of approximately 90 degrees will be close to (elliptical, circular) in shape

Answer 7

circular

Question 8

The angle of impact of an individual bloodstain can be estimated using the ratio of _____ divided by _____.

Answer 8

width; length

Question 9

_____ is the most common type of blood spatter found at a crime scene and is produced when an object forcefully contacts a source of blood.

Answer 9

impact spatter

Question 10

T or F: Forward spatter consists of the blood projected backward from the source, and back spatter is projected outward and away from the source.

Answer 10

False

Question 11

The classifications of impact spatter based on the size of droplets and from the velocity of an applied force are _____, _____, and _____.

Answer 11

low velocity spatter,
medium velocity spatter,
high velocity spatter

Question 12

T or F: The velocity of an applied force is a good way to classify impact patterns and to determine the kind of force that produced them.

Answer 12

False

Question 13

The _____ is the point on a two-dimensional plane from which the drops originated.

Answer 13

area of convergence

Question 14

The _____ of a bloodstain pattern in a three-dimensional space illustrates the position of the victim or suspect when the stain-producing event took place.

Answer 14

area of origin.

Question 15

The _____ method is used at the crime scene to determine the area of origin.

Answer 15

string

Question 16

A(n) _____ is created by contact between a bloody object and a surface.

Answer 16

transfer pattern

Question 17

The pattern made by a bloody object dragged across a surface will (lighten or darken) as the object moves away from the point of contact.

Answer 17

lighten

Question 18

T or F: Footwear transfer patterns created by an individual who was running typically show imprints with more space between them than those of an individual who was walking.

Answer 18

True

Question 19

T or F: The direction of a flow pattern may show movements of objects or bodies while the flow was still in progress or after the blood had dried.

Answer 19

True

Question 20

The approximate drying time of a _____ of blood determined by experimentation is related to the environmental conditions of the scene and may suggest how much time has elapsed since its deposition.

Answer 20

pool

Question 21

The edges of a bloodstain will generally _____ within 50 seconds of deposition and be left intact even if the central area of a bloodstain is altered by a wiping motion.

Answer 21

skeletonize

Question 22

A(n) _____ pattern commonly originates from repeated strikes from weapons or fists and is characterized by an arc pattern of separate drops showing directionality.

Answer 22

castoff

Question 23

T or F: Characteristics of a cast-off pattern arc cannot give clues about the kind of object that was used to produce the pattern.

Answer 23

False

Question 24

When an injury to an artery is suffered, the pressure of the continuing pumping of blood projects blood out of the injured area in spurts, creating a pattern known as _____.

Answer 24

arterial spray spatter

Question 25

If a(n) _____ pattern is found at a scene, it may show movement, lead to a discarded weapon, or provide identification of the suspect by his or her own blood.

Answer 25

trail

Question 26

A bloodstain pattern created by _____ features bubbles of oxygen in the drying drops and may be lighter in color than impact spatter.

Answer 26

Expirated blood

Question 27

The shape and size of the blank space, or _____, created when an object blocks the deposition of spatter onto a surface and is then removed, may give a clue about the size and shape of the missing object of person.

Answer 27

void.

Question 28

T or F: Each bloodstain pattern found at a crime scene should be noted, studied, and photographed.

Answer 28

True

Question 29

When documenting bloodstain patterns, the _____ involves setting up a grid of squares of known dimensions over the entire pattern and taking overview, medium-range, and close-up photographs with and without the grid.

Answer 29

grid method

Question 30

The _____ method of bloodstain documentation involves setting up a border of rulers around the pattern and then placing a small ruler next to each stain to show relative position and size in photographs

Answer 30

perimeter ruler method

Question 31

T or F: The pointed end of a bloodstain always faces toward its direction of travel.

Answer 31

True

Question 32

Answer 32

A. 1,5,8 B. 3,4,9 C. Drop 2 = right to left Drop 7 = bottom to top

Question 33

Define Satelite spatter

Answer 33

Blood spatter around parent stain, with blood droplets whose pointed ends face against the direction of travel

Question 34

Define low-velocity spatter

Answer 34

Drop spatter at 4mm or more, showing force was moving up to 5 FPS, usually associated spatter by gravity alone.

Question 35

Define medium-velocity spatter

Answer 35

Drop spatter between 1-4mm, showing force moving at 5-25 FPS, usually associated with blunt-force trauma.

Question 36

Define high-velocity spatter

Answer 36

Drop spatter less then 1mm, showing force moving at 100 FPS, usually associated with gunshot exit wounds or explosions.

Question 37

Answer 37

Point of convergence, where the victim was standing.

Question 38

Answer 38

High - velocity spatter w/ muzzle blast burn (what else do you notice)

Question 39

Answer 39

Type: Cast off (what else do you notice)

Question 40

Answer 40

Type: Arterial Spray Spatter (what else do you notice)

Question 41

Answer 41

Type: Expired blood pattern (expelled from mouth/coughing) (what else do you notice).

Question 42

Answer 42

Type: Void pattern (no spatter behind door...door was open when spatter hit wall)(what else do you notice).

Question 43

Answer 43

Transfer pattern (what else do you notice)

Question 44

Answer 44

Type: Flow pattern (what else do you notice)

Question 45

Answer 45

Skeletonization (what else do you notice)

Question 46

Answer 46

Drip trail (what else do you notice)