What can a void tell a spatter analyst quizlet?

A void is an area within a deposited spatter pattern that is clear of spatter, caused by an object or person blocking the area at the time of the spatter’s deposition. They can also help to establish the body position of the victim or assailant at the time of the incident.

An object that leaves a void in a bloodstain pattern will have a matching bloodstain pattern on its surface, allowing analysts to replace it in the scene if found. Void patterns are most useful for establishing the position of the victim(s) and assailant(s) within the scene.

Similarly, how can an investigator tell the direction of travel of blood from the shape of a bloodstain? The pointed end (tail) always faces in its direction of origin.

Then, what is a void pattern How might a void pattern be useful to investigators?

It is created when an object blocks the deposition of blood spatter onto a target surface or area//they can help investigators establish the position of the victim or assailant at the time of the incident.

What kind of pattern is produced by a gunshot?

Blood spatter that could form during a shooting incident When a person is shot, for example in the head, two kinds of typical blood spatter patterns can be formed. Due to the high speed of the bullet and the damage that is caused in the wound channel, “back spatter” and “forward spatter” can be created.

What can you learn from blood spatter?

The shape and size of these droplets can help to determine the positioning of a victim, the type of weapon used, and the force used in the crime. On the other hand, blood drip stains appear when only gravity works on the blood.

What is blood spatter analysis used for?

Bloodstain Pattern Analysis (BPA) is the study and analysis of bloodstains at a known or suspected crime scene with the purpose of drawing conclusions about the nature, timing and other details of the crime. It is one of the several specialties of forensic science.

What is the difference between a wipe and a swipe?

As verbs the difference between swipe and wipe is that swipe is to steal or snatch while wipe is to move an object over, maintaining contact, with the intention of removing some substance from the surface (cf rub).

What two forces does a blood droplet experience as it falls?

Blood forms a spherical shape (perfect circular shape) almost immediately upon separating from the blood source. The spherical shape is caused by the surface tension of the blood. Surface Tension causes the blood drop to pull itself in; both horizontally and vertically.

What qualifies as a projected bloodstain?

Projected bloodstains are created when an exposed blood source is subjected to an action or force, greater than the force of gravity. The size, shape, and number of resulting stains will depend, primarily, on the amount of force utilized to strike the blood source.

What are the two phases of bloodstain pattern analysis?

Bloodstain pattern analysis is performed in two phases: pattern analysis and reconstruction. 1. Pattern Analysis looks at the physical characteristics of the stain patterns including size, shape, distribution, overall appearance, location and surface texture where the stains are found.

When was blood spatter analysis first used?

The first methodical study of blood spatters, titled “Concerning the Origin, Shape, Direction and Distribution of the Bloodstains Following Head Wounds Caused by Blows,” was published in 1895 by Dr. Eduard Piotrowski of the University of Krakow in Poland.

How does low velocity spatter occur?

Low velocity blood spatter can caused by blood dripping. For example blood dripping from a nose bleed. The force of the blood hitting a surface for low velocity blood spatter is 5 feet per second or less. This causes the blood droplets to be large in diameter (between 4 and 8mm.)

How is a simple transfer pattern created?

Simple transfer patterns are produced when the object makes contact with the surface and is removed without any movement of the object. The size and general shape of the object may be seen in a simple transfer. Other transfers may be caused by movement of the bloody object across a surface.

What is the difference between forward and back spatter?

What is the difference between forward spatter and back spatter? Which is more likely to be deposited on the object or person creating the impact? Answer: Forward spatter is projected outward and away from the source; back spatter consists of the blood projected backward from the source.

What kinds of information can bloodstain patterns reveal about a crime scene?

Bloodstain pattern analysis is the use of the bloodstain size, shape, and distribution patterns found at a crime scene in order to determine the bloodshed event(s). Bloodstain patterns reveal not “who” but “what and how” with regard to the bloodshed event.

What is the most common type of bloodstain pattern found at a crime scene?

The most common type of bloodstain pattern found at a crime scene is impact spatter. The pattern occurs when an object impacts the source of the blood. Spatter projected outward and away from the source, such as an exit wound, is called forward spatter.

What determines the size of blood drops?

What determines the size of blood droplets is the size of the object used to inflict damage. Small or pointed surfaces create smaller and large or blunt surfaces create larger and wider in pattern. Blood drops in a tear drop shape with a tail have likely fallen at a different angle.

Why is it important to determine the point of origin of a bloodstain?

Because it helps them make an accurate calculation of the angle of impact when they analyze blood that has hit a surface after being in flight. Knowing the angle of impact is important for determining from which point or area the blood originated.