Deck 4: Crime Scene Reconstruction: Blood Stain Pattern Analysis

Question 1

At the crime scene,the string method is used to find the ________ of an impact spatter pattern.

A) Area of origin
B) Void pattern
C) Area of convergence
D) Velocity classification

Answer 1

A

Question 2

The approximate drying time of a pool of blood can be used to estimate timing of events at a crime scene and is dependent upon:

A) The clotting ability of the blood.
B) The blood type of the blood.
C) The environmental condition of the scene.
D) The method of deposition.

Answer 2

C

Question 3

A trail pattern leading away from the victim at a stabbing scene was most likely created by:

A) A victim's arterial wound.
B) Blood dripping from the murder weapon.
C) Postmortem movement of the victim.
D) Blood expelled from a respiratory injury.

Answer 3

B

Question 4

The deposition of backward spatter produced by a gunshot wound is determined by:

A) The location of the injury.
B) The size of the wound created.
C) The distance between the victim and the muzzle.
D) All of the above

Question 5

Which weapon would create cast-off patterns consisting of small droplets in a linear pattern?

A) Baseball bat
B) Knife
C) Wooden plank
D) All of the above

Question 6

The pointed end of a bloodstain always faces:

A) Opposite its direction of travel.
B) Toward the direction from which the force came.
C) Its direction of travel.
D) Toward the position of the blood source.

Question 7

Proper location and documentation of bloodstain patterns at the crime scene is the responsibility of:

A) A bloodstain analysis specialist.
B) The lead investigator.
C) Criminalists and specialists.
D) All crime scene personnel.

Question 8

The removal of an object or surface that was located between the origin of blood and the target surface during the bloodstain deposition leaves behind:

A) Expirated blood.
B) A void.
C) Blowback spatter.
D) An unidentifiable pattern.

Question 9

The skeletonized perimeter of a bloodstain can be used to interpret:

A) The kind of force that produced the bloodstain.
B) The time that elapsed between deposition of the stain and alteration of the stain.
C) The source of the bloodstain.
D) Both B and C

Question 10

When an object with blood on it touches one that does not have blood on it,this produces a(n):

A) Flow.
B) Indistinguishable pattern.
C) Contact pattern.
D) Trail pattern.

Question 11

The intersection of straight lines through the long axis of several individual bloodstains in an impact spatter pattern illustrates the ________ of the pattern.

A) Area of origin
B) Void pattern
C) Area of convergence
D) Velocity classification

Question 12

A blood droplet deposited at an angle of impact of about 90º (directly vertical to the surface)will:

A) Show acute elongation.
B) Feature a tail showing the directionality.
C) Be elliptical in shape.
D) Be approximately circular in shape.

Question 13

The velocity classification of an impact spatter pattern:

A) Cannot illuminate the specific events that produced the pattern.
B) Can determine the kind of action that produced the pattern.
C) Is never used for descriptive purposes.
D) Can only be determined by a trained bloodstain pattern analyst.

Question 14

The amount of spatter from a blood droplet falling on a hard,non-porous surface is ________ that of a drop of blood of equal size,falling from the same distance,onto a softer,porous surface.

A) The same as
B) Less than
C) Greater than

Question 15

Widely spaced bloody shoeprints with satellite spatter between the shoeprints were likely deposited by an individual who was:

A) Standing in place.
B) Walking slowly.
C) Running.
D) Carrying a bloody weapon.

Question 16

The pressure of the pumping of oxygenated blood out of an injury causes bright red-colored blood to spurt out and form a(n):

A) Void pattern.
B) Expirated pattern.
C) Arterial spray pattern.
D) Both B and C

Question 17

The most common type of bloodstain pattern found at a crime scene is:

A) Cast-off spatter.
B) Void spatter.
C) Impact spatter.
D) Arterial spray.

Question 18

The direction of a ________ may show movements of objects or bodies while the pattern was still forming or after the blood has dried.

A) Flow pattern
B) Cast-off pattern
C) Bloodstain tail
D) Trail pattern

Question 19

If a murder victim's blood is found in the muzzle of a firearm:

A) No conclusion can be made.
B) It can be concluded that the firearm is the murder weapon.
C) It can be concluded that the firearm was present during injury to the victim.
D) It can be concluded that the owner of the firearm is the perpetrator.

Question 20

In the grid method of bloodstain documentation,a grid of squares of known dimensions is created over an entire pattern in order to:

A) Show the relative sizes of bloodstains in photographs.
B) Prevent contamination of the bloodstains.
C) Collect bloodstains for delivery to the laboratory.
D) All of the above

Question 21

An impact pattern consisting of large separate drops with diameters of 5 millimeters is:

A) Low-velocity spatter.
B) Medium-velocity spatter.
C) High-velocity spatter.
D) Both A and B

Question 22

What is created when an object with blood on it touches one that does not have blood on it?

A) Flow pattern
B) Void pattern
C) Cast-off pattern
D) Transfer pattern

Question 23

Droplets of ________ are very small.They may not travel far and could be overlooked.

A) High-velocity spatter
B) Transfer patterns
C) Medium-velocity spatter
D) Low-velocity spatter

Question 24

What information can an investigator gain from the location of the area of origin of a bloodstain pattern?

A) Position of weapons at a crime scene
B) Position of person from which pattern originated
C) Type of force used
D) Identity of the suspect

Question 25

Crime scene reconstruction involves the efforts of all EXCEPT the:

A) Trial judge.
B) Medical examiner.
C) Police.
D) Criminalist.

Question 26

When an object blocks the deposition of blood spatter onto a target surface or object,the result is a:

A) Transfer pattern.
B) Flow pattern.
C) Void pattern.
D) Cast-off pattern.

Question 27

By counting and pairing the patterns of a(n)________ pattern,an investigator can estimate the minimum number of blows inflicted upon a victim.

A) Impact
B) Arterial spray
C) Void
D) Cast-off

Question 28

Which of the following is of paramount importance in the interpretation of bloodstain patterns?

A) The direction of impact
B) The surface texture
C) The angle of impact
D) The amount of blood

Question 29

In general,as both the force and velocity of impact increase,what happens to the diameter of the resulting blood droplets?

A) Increases
B) Stays the same
C) Decreases
D) The diameter is unaffected by force and velocity.

Question 30

________ transfer patterns are produced when the object makes contact with the surface and the object is removed without any movement.

A) Void
B) Contact
C) Simple
D) Flow

Question 31

A blood stain that impacts a surface at a low angle will have a ________ tail than one that impacts at a higher angle.

A) Longer
B) Shorter
C) Wider
D) Narrower

Question 32

The presence of a cast-off pattern shows that there were more than ________ blow(s)delivered:

A) One
B) Two
C) Five
D) The cast-off pattern cannot tell how many blows were delivered.

Question 33

Setting up a rectangular border of rulers around the patterns and then placing a small ruler next to each stain describes the:

A) String method
B) Stake method
C) Grid method
D) Perimeter ruler method

Question 34

Generally,bloodstain diameter ________ as height increases.

A) Decreases
B) Remains unchanged
C) Increases
D) Increases lengthwise and decreases widthwise

Question 35

Crime scene reconstruction requires the piecing together of:

A) Accounts given by witnesses and suspects.
B) Input from the medical examiner.
C) The story told by evidence recovered at the crime scene.
D) All of the above

Question 36

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.

A) Void
B) Area of convergence
C) Directionality
D) Area of origin

Question 37

Drops propelled from a blunt surface will be larger and the pattern will be:

A) Narrow.
B) Wide.
C) Linear.
D) Thin.

Question 38

Rough surfaces usually result in stains with:

A) Forward spatter.
B) Back spatter.
C) Blow-back spatter.
D) Satellite spatter.

Question 39

Setting up squares of known dimension over the entire pattern describes the:

A) String method.
B) Stake method.
C) Grid method.
D) Perimeter ruler method.

Question 40

Crime scene reconstructions have the best chance of accuracy if:

A) Investigators exclude all testimonial evidence.
B) Investigators use proper documentation and collection methods for all types of evidence.
C) Investigators process all evidence at the crime laboratory.
D) Investigators trust their first instincts and test their first theories.

Question 41

Void spatter is the most common type of bloodstain pattern found at a crime scene.

Question 42

What should one surmise if a flow found on an object or body does not appear consistent with the direction of gravity?

A) The object or body was within 5 feet of the blood source.
B) The object or body was moved after the blood had dried.
C) The object or body was not moved.
D) The object or body was at a lower temperature than the blood.

Question 43

In general,as both the force and velocity of impact increase,the diameter of the resulting blood droplets increases.

Question 44

The tails of the drops in a trail pattern point in the direction that the person was moving.

Question 45

Forward spatter is more likely to be deposited on the object or person creating the impact.

Question 46

The pointed end of a bloodstain always faces its direction of travel.

Question 47

The sizes of the drops in a cast-off pattern are not related to the size of the point from which they were propelled.

Question 48

Drops propelled from a small or pointed surface will be smaller and the pattern more linear.

Question 49

A bloodstain that impacts a surface at a low angle with have a shorter tail than one that impacts at a higher angle.

Question 50

The flow pattern on an object or body can help determine if the body was moved after the blood had dried.

Question 51

Physical evidence that can be used to aid in a crime scene reconstruction includes:

A) Blood spatters.
B) Gunshot residues.
C) Glass fragments.
D) All of the above

Question 52

The location of injury,the size of the wound created,the distance between the victim and the muzzle of the weapon all affect the amount of backward spatter that occurs.

Question 53

Pools of blood are not reliable to use in reconstruction or determining the amount of time that has elapsed since the blood was deposited.

Question 54

Since droplets of high-velocity spatter are very small,they may not travel far.

Question 55

Expirated blood is blood that is expelled from the mouth or nose from an external injury.

Question 56

Voids may help investigators establish the body position of the victim or assailant at the time of the incident.

Question 57

The process of crime scene reconstruction may enlist the expertise of all of the following EXCEPT:

A) A trained criminalist.
B) A criminal personality profiler.
C) A medical examiner.
D) A forensic anthropologist.

Question 58

The first transfer pattern will be lighter in color while subsequent transfers will be increasingly dark and heavy.

Question 59

A flow pattern is created when an object blocks the deposition of blood spatter onto a target surface or object.

Question 60

Back spatter consists of the blood projected backward from the source.

Question 61

In general,as both the force and velocity of impact increase,the diameter of the resulting blood droplets ________.

Question 62

Gunshot exit wounds commonly produce medium-velocity spatter,while explosions produce high-velocity spatter.

Question 63

________ spatter is projected outward and away from the source.

Question 64

Expirated blood also may be lighter in color as a result of dilution by ________.

Question 65

Simple ________ patterns are produced when the object makes contact with the surface and is removed without any movement of the object.

Question 66

The ________ effect occurs when back spatter strikes the gunman and enters the gun muzzle.

Question 67

Drops propelled from a large or blunt surface will be ________ and the pattern wider.

Question 68

Typically the blood expelled from impact wounds is not as bright red as the blood expelled from the ________.

Question 69

A(n)________ pattern is a pattern made by drops or large amounts of blood flowing by the pull of gravity.

Question 70

Blunt force trauma is normally associated with ________-velocity spatter.

Question 71

In general,as the force of the impact on the source of blood increases,the velocity of the blood droplets emanating from the source ________.

Question 72

Drops propelled from a pointed surface will be smaller and the pattern more ________.

Question 73

The less blood on an object,the smaller the stains produced.

Question 74

Cast-off patterns can show the ________ number of blows.

Question 75

The presence of bubbles of oxygen in the drops can differentiate ________ blood from other types of bloodstains.

Question 76

Often,reconstruction requires the involvement of a medical examiner and at least one ________.

Question 77

The velocity at which blood strikes a surface is not useful to describe the specific events that produced the spatter pattern.

Question 78

More circular stains are found where the person was moving slowly enough to not form ________.

Question 79

During crime scene reconstruction,no evidence or data should ever be excluded.

Question 80

The location of injury,the size of the wound created,the distance between the victim and the muzzle of the weapon all affect the amount of ________ spatter that occurs.