Analyzing Gunshot Wounds

Whenever a crime such as a shooting occurs and authorities are called to investigate, it is up to an experienced detective to make important assessments at the scene of the crime.

When a firearm is discharged, the projectile, or bullet, is not the only thing that leaves the barrel. Not only does the bullet exit the barrel but so do other items. For one, gases are produced by the combustion of gun powder and expand as it pushes the bullet through. In addition, metal fragments from the cartridge case and carbon and soot from the ignition of the primer also leave the barrel.

All of this minute material leaves behind trace amounts on the victim when a firearm is fired at a certain distance. What if the skin surrounding the wound displays what is known as a powder tattoo, which is a stain created by soot and carbon. In this scenario, it can be concluded that the gun was discharged no more than two feet from the victim.

By conducting a similar experiment in a ballistics lab, criminalists can compare the resulting powder pattern and the proportion of the burned and unburned powder against the trace amounts of evidence found on the victim’s body or clothing. It can be determined experimentally the actual firing distance of the weapon from the victim.

If the muzzle, or the end of the barrel, of the firearm, was in direct contact with the victim, a wound called a contact wound will show up oftentimes accompanied by the muzzle’s indentation embedded in the skin of the victim.

At the scene of a shooting, crime scene investigators (CSI’s) can use the gunshot wound as evidence to make a preliminary determination of whether or not the injury was due to a suicide or a homicide.

A wound suggesting that the firearm was discharged from more than just a few inches away or a gunshot that traversed clothing tends to exclude a suicide and lean toward a homicide. By considering the location of the wound (for example, the back of the spine), the angle of the bullet’s trajectory, or the absence of the weapon at the scene, one can definitely exclude the possibility of a suicide.

If, on the other hand, the gunshot wound reveals that the firearm was held against the skin, and if the wound was in the left temple, assuming at the victim was left-handed, one can lean toward suicide. It is highly unlikely that suicides fire through clothing except when the victim inflicts a wound to his own chest. The murder weapon will most likely be found at the scene with the victim holding tightly onto the gun due to a cadaveric spasm.