Blood Splatters in Criminalogy - Essay Example

Final Exam The area of origin is the location from which the blood that produced the blood splatter originated. The area of origin is a combination of the point of convergence and the angular data. The point of converge projects the blood stain pattern on a two dimensional representation. The long axis of the blood stain is traced back to a common point.2. Blood splatters can give information about the origins of the stain, what objects were involved, the positions of the victims and actors, movement at the scene, directionality, and the distance between the origin at the time of bloodshed and the impact areas of blood splatter.

This information can help investigators decide who or what was there or not there, what happened, what events happened, and when they happened or in what order. 3. A. Low Velocity- includes weaker force such as normal gravity, pattern transferring by hand, foot, or hair, and flowing or splashed blood. The stain produced is normally 3mm or larger. B. Medium Velocity- Increased force that comes from weapons such as clubs, or blunt objects like fists, tools, bats, or knives. The stain produced is usually 1-3mm. C. High Velocity- Includes high force from weapons such as guns or other high speed objects.

The stain produced is usually less than 1 mm.4. Velocity refers to the amount of force and speed behind the object or item that causes the blood spatter. A lower velocity indicates weaker, slower force that produces large spatters while a higher velocity indicates stronger, faster force that produce small blood spatters. 5. To determine the area of origin for a blood spatter, the investigator looks at the point of convergence and the angular information and data such as the angle of impact, the target surface area, the projected string, and the blood stain. 6. Trace evidence can be used as circumstantial evidence and is often the only evidence available from corroboration. 7. A.

Building materials can be useful if investigators can determine the class or possibly find a common origin. Can be collected in vehicles, with broken tool pieces, tools, perps, and tool marks, and should be gathered from all damaged areas. B. Clothing can yield class and individual characteristics. Is often useful in burglary, hit and runs, and homicide cases. Can individualize chemical, physical, and micro characteristics. Normally tested for color, dye composition, type of fiber, and how the cloth is woven. C. Hair has DNA properties and can be studied microscopically and can be extremely useful if belonging to a person not connected to the victim.

Hair can be collected by eye ball or bright light discovery and picked or by using the taping method. 8. The crime scene in an arson case is never the same at the time of investigation as it was at the time of the crime. There are only two reconstruction purposes: locate the origin of the fire and determine the cause of the fire. This is made difficult because things have been moved, stepped on, removed, destroyed, or soaked. Investigators study the color of smoke, the smell of smoke, depth of char, spalling, oxidation, glass, protection and pour patterns.9. 10.

Class characteristics are common characteristics shared by an object to objects of a similar nature. For example, Wolverine boots will all have the same basic design on the bottom of the boot as other Wolverine boots, so and investigator can distinguish a Wolverine boot from a Rocky Mountain boot based on general class differences. Individual characteristics in footwear will include material on the boot, such as dirt, rocks, dust blood, paint. It will also have wear and tear in certain areas and rips, scrapes, or holes from other objects.

The more these types of characteristics the investigator finds, the more likely he will be to determine a match. Extra Credit1. Because no two people will walk the same exact path all the time, our shoes are all unique because they change as we use them. Footwear can be punctured by rocks, nails, or knives. They can be scraped or dented by falling objects, sticks, and materials. They can gather mud, blood, dirt, liquids and other materials that can be tested and matched. Each person has a combination of weight and weight distribution that forms wear and tear on the shoes.

A female who is pigeon-toed will have completely different wear and tear on her footwear than a large male who is bow-legged. The more of these characteristics a footwear surface contains, the more conclusive the evidence that a print does or does not match a certain piece of footwear.