Fire Investigation - A New Frontier in Forensic Science
Frequent fire accidents with unknown causes have give rise to a specialised area in the forensic science - the fire investigation. This knowledge is important in administering justice for both the accused and the innocent.
About fire investigations
Every time if there are any house fire involving deaths, there will be always unanswered questions surrounding the burnt corpses. Other types of fires include car fires and arson. Fire investigators searching throughout the house to find burnt remains such as partly burnt bedding, clothing, and soil from pots for clues on how was the fire started. These samples are then extracted and analyzed by gas chromatography. Although this method is quite reliable for determining the cause of fire, but the exact process of burning is unknown. This may lead to wrongful conviction of a suspect under provision of limited evidence. Till the present, the limited data are available for the burning of corpses. Some investigations include experimenting on pig corpses. However, there is a great discrepancy between the anatomies of a pig as compared to a human. The other method is the post-hoc examination of burnt corpses where it provided limited details of burning.
Statistics and all information regarding fire investigation and arsons.
Human corpses studies
A forensic scientist at the University of West Florida in Pensacola named Elayne Pope, lead the investigation on how human burns exactly. They are the only one who is publishing their work on this field. They had done a systematic study of burning corpses in this area. Up to now, the team had studied more than 30 whole corpses and other body parts in different circumstances. They hoped that more bodies will be available for experimentation so that the facts established quickly.
So what happens when a body is burning? According to a fire investigator at Fire-Ex Forensics in Vallejo, California, named John DeHaan, who works with Pope, says that a human limb burns a little like a tree branch. The skin of the body and limbs starts to fry and peel off when it is burning. After only 5 minutes, the dermal layer underneath the epidermis will break up and split, exposing the underlying fat layer. The yellow fat layer then begins to leak out. The fat is a good fuel of burning only when there is a material acting as a wick such as clothing or charred wood. The fat absorbed through the wick and as it vapourises, the body continues to burn. Sufficient wick material needed to support the body to burn for 7 hours. Only when the body exposed to higher temperature, the blisters will formed when the moisture drawn out from the tissue. If a flammable liquid dumped on a person, it will only burn for a minute, where the body is not completely destroyed.
What happened to body limbs during burning?
As hands and feet are burning, the soft tissues supporting the limbs quickly burnt away. Thus, small bones such as metacarpal and phalanges will fragment and break off. We may overlook these bones as ashes and dust, when a fire does occurred. Teeth or fragments of bones can leave clues for fire investigators even someone has agitated the bones.
As the body started to burn, fingers and hands contracted and curled. This is because heat can cause muscles to dry out and contract. This phenomenon makes the limbs of a burnt corpse to move and flex and adopt special characteristic postures depending on situation. For example, when a body is laid flat on the ground where hands straightened close to the body, 30 minutes to 1 hour of burning can make the arms raised like fending off an attacker. This can lead to the fire investigators to suspect a foul play. Therefore, in my opinion, by carefully look at the degree of burning and the postures adopted by the corpse, it is possible to estimate the time of death of the corpse and how was the fire started. It can also give more reliable information for fire investigators from evidence-based research.
The burning of human skull
Skulls do not explode when it is burning but some of the bones may fragment and become brittle during burning. These bones can break off as it looks like as if it exploded. Normally, the upper skull is mostly charred because it has only a thin layer of soft tissue. When someone was shot or stabbed, the wounds open early before fires started. The part of the bone will be more exposed to fire, thus making the part of the bone more charred than the other parts of the bone. Thus, investigators can gain some clues by looking at the marks made on the bones by fire.
The significance of such studies
Investigation into the process of burning enables the burnt corpses examined in its original place. Additional evidence collected besides the evidence found from the gas chromatography. However, evidence often lost when a fire fighter is trying to save the victims. This is because during the saving process, some dead victims mistakenly rescued as alive.
This potential field of investigation is useful in investigating the causes of fires such as house fires to give more detailed evidence. Michael Baden, a chief forensic pathologist for the New York State Police, said that DNA is only helpful in 10 percent of the cases. This help to prevent innocent people from being convicted and the murderer quickly be identified. Furthermore, the causes of fire be determined much more quickly.
I think that the governments of the world should therefore endorse this intriguing new field of investigation by a special funding program so that accidental fires or arson will be effectively cut down to a low-level. Public awareness needed so that they are willing to give their bodies after death for useful scientific researches such as fire investigations.