Decomposition refers to the reduction of the body of a formerly living organism into simpler forms of matter. The body of a living organism begins to decompose shortly after death. Such decomposition can be simplified in two stages: In the first stage, it is limited to the production of vapors. In the second stage, liquid materials form and the flesh or plant matter begins to decompose.

There are environmental influences that will affect decomposition. A body that is exposed to air will decompose more quickly and will have more insect activity. A buried body will decompose eight times slower than a body exposed to air. This is due in part to limited insect activity and possibly lower temperatures. Likewise a body submerged in water decomposes at half the rate of an exposed body. The rate of decomposition depends on the temperature of the water. Cold water will allow slow decomposition and warm water causes faster decomposition. The body is also shielded from insect activity as long as it is submerged.

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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Forensic art is a law enforcement artistic technique used in the identification, apprehension, or conviction of wanted persons.  Forensic art encompasses several disciplines including composite art, image modification, age progression, post-mortem reconstruction and demonstrative evidence. However, composite art is traditionally the most commonly known discipline of forensic art. The art of composite drawing has been used by police agencies throughout history. When one recalls the Old West, the classic wanted poster with a drawing of a “Bad Guy” comes to mind. These drawings were composites.

Composite Art is an unusual marriage of two unlikely disciplines, police investigative work and art. The cop-artist, almost an oxymoron, possesses both skills. The artist can create a quality facial drawing with assured confidence. Though drawing skills are important parts of composite art, the real challenge is in the ability to interview and relate to a victim or witness. The purpose is to successfully gather, interpret and illustrate the information obtained from the victim’s memory.

In the past twenty years, the discipline of composite art has evolved into forensic art. The forensic artist possesses knowledge of victim psychology, post-mortem reconstruction and human aging. These artists currently use new computer technologies and digital imagery to create more successful investigative images.

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.

Time of Death seems like a simple and strait forward concept - it’s the exact time that the victim drew his or her last breath, right? Wrong. Time of deaths may actually come in three different forms:

Estimated: The best guess as determined by the ME.
Legal: The time when the body was discovered or pronounced dead. The legal time is also the time printed on the death certificate.
Physiological: The time at which the victim’s vital functions actually ceased.

Times of death may differ by days, weeks, even months, if the body isn’t found until well after physiological death has occurred.. For example, if a serial killer kills a victim in July, but the body isn’t discovered until October, the physiological death took place in July , but the legal death is in October. The ME’s estimated time of death could be in July or even June or August.

The only absolutely accurate determination of the death is under the uncommon circumstances in which a person dies with a physician or other skilled medical professional present. many deaths occur during sleep, and accidental  deaths often occur when the victim is alone, and so do suicidal deaths. In homicides, the perpetrator typically is the only witness, and even if he checks his watch, he’s not likely to pass on that information.

- Brandon Anderson