by Dr. Jennifer JohnsonCourtesy of the Academy of Forensic Nursing
FORENSIC NURSE EXAMINERS and medical professionals may encounter patients who have
sustained gunshot wounds. They may be either self-inflicted or inflicted by
others. The forensic nurse examiner evaluates the patient along with other
medical providers who may be providing life-sustaining medical interventions.
assessment outcome is to assure proper interpretation of the wound(s), obtain photographs
of the physical presentation both before and after medical intervention, and clean
the injury. The forensic nurse assures appropriate handling of valuable
forensic evidence, including the patient’s clothing and the retained projectile,
while maintaining chain of custody. Ultimately, the forensic nurse will provide
their findings within the medical record to assure there are no erroneous
identifications of the entrance and or exit wounds which could cause profound
issues in subsequent legal proceedings.
wounds provide a wealth of information just by focusing on wound patterns,
range of fire, and trajectory. Gunshot wounds are either penetrating, where
there is one single entrance wound and no exit, or perforating, where
there is both an entrance and an exit wound. Beyond the entrance and potential
exit wound, there are many other physical characteristics that may be present
during evaluation. Rather than the size of the wounds, other physical
characteristics will aid in differentiating between the entrance and exit
wounds have six physical findings that may be present:
1) The abrasion
collar, which is caused by the projectile entering the skin. An abrasion
collar may be circular in fashion; however, if the projectile is traveling and
enters the body at an angle, this will result in an angled or comet-tail
abrasion collar because the bottom side of the projectile has more contact with
the skin. This type of abrasion collar can provide information about trajectory
and the direction the projectile was traveling through the body.
physical finding is tattooing or stippling which can be caused by
3) If the
gunpowder is burned, then the carbon abrasion residue called soot may be
present on the skin, which may be wiped away. Soot can make direct
visualization of the abrasion collar difficult to the examiner. The recommended
practice would be to photograph the injury as it appears, and then wipe away
the soot to visualize the abrasion collar, and then obtain additional
photographs. Soot will only be present in those gunshot wounds that are close
range of fire.
4) The skin
may be seared from the flame emitted from the barrel of the gun, or 5) triangular
shaped tears may form from the gas that has been injected into the skin,
causing the skin to expand to a point where it rips and tears.
some instances, there may be the presence of a muzzle contusion which
results from the injected gas pushing the skin against the barrel of the gun
wounds may also have irregular borders, even though there may be an absence of
soot and seared skin; there is a possibility of having no tattooing or
stippling apparent, but still presenting with the triangular shaped tears.
of fire is the distance from the gun to the impacted anatomical location on the
body. The range of fire will also present physical characteristics at the wound
location. Contact with the skin, even through clothing, will result in an
abrasion collar, seared skin, triangular shaped tears, and the presence of
soot. Close contact, which is zero to six inches, will result in the presence
of an abrasion collar and the presence of soot. Intermediate range of fire,
which is up to 48 inches, will present with an abrasion collar and tattooing or
stippling. Distant indeterminate range of fire is greater than 48 inches and
the singular physical finding will be that of an abrasion collar.
the examiner assesses an individual that has sustained a gunshot wound, the
examiner notes the entrance and exit wound characteristics, identifies the
range of fire based on the physical characteristics noted, and then identifies
the trajectory of the projectile. Trajectory is the path taken by the
projectile into and through the body to its resting place, either inside the
body or through an exit wound. This is documented as superior to inferior,
medial to lateral, and anterior to posterior in relation to the entrance and
evaluating an individual who has sustained a gunshot wound, there are some
important questions to ask:
questions will aid in the evaluation of the wound, and either corroborate or
refute the information being disclosed.
An Unusual Case Study
not every day that an examiner evaluates an individual with two entrance wounds
and two exit wounds. The following case will showcase the physical presentation
of a self-sustained gunshot wound. A man in his 20s presented to the emergency
department after a gunshot wound. He described placing the firearm into the
front right pocket of his jeans. The gun discharged and the projectile traveled
superior to inferior and from lateral to medial through his right testicle and
exited through his left testicle. In this case, there was contact with clothing,
as the firearm was located within the front pocket. Gases were injected into
the pelvic area where the barrel was located. The gases that were ejected were
caught between the pocket liner and the underlying skin. As such, not all the
gases went into the wound, but on the surface of the skin the presentation of
seared skin, soot, and triangular-shaped tears was noted. The pocket liner
expanded, and the flame as well as the bullet made contact with the skin,
resulting in additional injury.
following pictures depict the wound presentations identified during the medical
image shows the entrance wound at the base of the right testicle, at the ten
o’clock position. Notice the soot and seared skin that is present. Close
examination shows there are triangular shaped tears present as well.
projectile traveled through the testicular region and exited through the left
testicle at the four o'clock position. Note the absence of seared skin and soot;
there is no stippling present; and there are some definitive triangular shaped
tears visualized on the superior portion of the wound.
the right-front pocket liner, bullet wipe and fiber defects were visualized.
Bullet wipe residue transfer caused when the projectile passes through the
pocket liner. The bullet wipe forms when the carbon residue present in the
barrel is transferred onto the projectile as it travels downward, which is then
deposited on the pocket liner. The bullet, which was a soft-nosed lead without
a jacket present, travels down the barrel and the lead wipes off onto the
residue was noted. This arises when the projectile is discharged and a puff of
residue from the primer is expelled initially out of the barrel and is
deposited on the pocket liner. There is also an absence of projectile
lubricant, which is an oil that may be deposited onto the projectile while it
is located either in the magazine or the chamber. When the projectile is
discharged, the lubricant then travels down the barrel and makes contact with
the right pocket liner.
the projectile then re-entered through a comet tail abrasion collar and traveled
inferiorly down the inner aspect of the medial aspect of the left thigh and
then exited. The projectile was ultimately located within the residence.
of the anatomical location of the injuries, the gunshot wound victim was
subsequently transported after stabilization for additional evaluation and
treatment in a trauma center under the care of a urologist.
case study is a fascinating look at the travel path and the injuries left
behind. To have all the injury presentations visualized on the skin—minus
tattooing or stippling—was, in this authors and examiner’s opinion, a once-in-a-lifetime
Editor's Note: In
the October issue of Evidence Technology Magazine, Dr. Jennifer Johnson will
provide an article on packaging evidence collected from gunshot
About the Author
Johnson is a board-certified women’s health nurse practitioner,
board-certified advanced forensic nurse, and sexual assault nurse examiner with
more than 20 years’ experience in practice. She previously developed and
managed a comprehensive forensics program in the Midwest and is the president
and owner of Johnson Legal Nurse Consulting, LLC. Johnson is an appointed
member of several professional and governmental organizations related to
forensic nursing, including the National Institute of Standards and
Technology/National Institute of Justice Evidence Management Project, and is
the President Elect and a Co-Founder of the Academy of Forensic Nursing.