A latent fingerprint is an example of a two-dimensional impression. A footwear impression in mud or a tool mark on a window frame is an example of a three-dimensional impression. If it’s not possible to submit the entire object containing the impression to the crime lab, a CSI makes a casting at the scene.

A casting kit might include multiple casting compounds (dental gypsum, Silicone rubber), snow wax (for making a cast in snow), a bowl, a spatula and cardboard boxes to hold the casts.

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Blood into Blood,

When blood drops fall into a blood drop that already hit a surface, the blood makes a satellite kind of shape. Other drops are usually made from that drop as well.

Expiratory blood,

Expiratory blood is blood is blood that come out of an air way or passage way as result of a cough or sneeze.

The inward spiral search: The CSI starts at the perimeter of the scene and works toward the center. Spiral patterns are a good method to use when there is only one CSI at the scene.

The outward spiral search: The CSI starts at the center of scene (or at the body) and works outward.

The parallel search: All of the members of the CSI team form a line. They walk in a straight line, at the same speed, from one end of crime scene to the other.

The grid search: A grid search is simply two parallel searches, offset by 90 degrees, performed one after the other.

The zone search: In a zone search, the CSI in charge divides the crime scene into sectors, and each team member takes one sector. Team members may then switch sectors and search again to ensure complete coverage.

There are alot of tools and equipment used by Crime Scene Investagators so ill list the most common tools and equipment used by Crime Scene Investagators,

• Crime Scene tape to cordon off the area
• A flashlight
• Latex gloves and paper shoe covers
• A magnifying glass and tweezers for collecting trace evidence
• A pen, logbook, and sketchpad
• Measuring tapes and rulers
• A camera with black and white and color film and several different lenses
• An assortment of paper, plastic, and glass containers store collected materials
• Sealable evidence bags
• Portable alternative light sources - laser, ultraviolet, and infrared
• Basic fingerprint kit with powders and lifting tape
• Casting kit for three-dimensional shoe and tire impressions
• Gunshot residue detection kit
• Chemicals to locate occult bloodstains
• Serology kit for sampling blood and other biological fluids
• Rape Kit

- Brandon Anderson

Bloodstain pattern analysis (BPA) is one of several specialties in the field of forensic science. The use of bloodstains as evidence is not new, however the application of modern science has brought it to a higher level. New technologies, especially advances in DNA analysis, are available for detectives and criminologists to use in solving crimes and apprehending offenders.

The science of bloodstain pattern analysis applies scientific knowledge from other fields to solve practical problems. Bloodstain pattern analysis draws on biology, chemistry, maths, and physics among scientific disciplines. As long as an analyst follows a scientific process, this applied science can produce strong, solid evidence, making it an effective tool for investigators.

For more information on bloodstain analysis and blood spatter alalysis I reccomend you take a look at these two older posts,

Blood Spatter Catagories

and

Blood Spatter Catagories Continued

- Brandon Anderson