This document discusses gunshot wounds from a legal medicine perspective. It defines different types of firearms and projectiles. It describes the mechanisms of injury from gunshot wounds and how to determine entrance and exit wounds. Factors that indicate wounds are self-inflicted, inflicted by others, or accidental are outlined. Tests for determining gunshot residue and identifying firearms are also summarized. The document provides details on shotgun wounds and examining gunshot wounds in different body areas.

1. Gunshot Wounds
Legal Medicine

2. Gunshot Wounds
Legal Medicine
Death or physical injuries brought about by powdered propelled substances
may be due to the following:
1. Firearm Shot – injury caused by missile propelled by the
explosion of the gunpowder located in the
cartridge shell and at the rear of the missile.
1. Detonation of high explosives as in grenades, bombs and mine explosion.
Firearm Wound
An instrument used for the propulsion of a projectile by the expansive
force of gases coming from the burning of gunpowder.
Includes rifles, muskets, shotguns, revolvers, pistols, and all other
deadly weapons from which a bullet, ball, shot, shell, or other missile may be
discharges by means of gunpowder or other explosives.
The barrel of any firearm shall be considered as complete firearm foe
all purposes thereof.

3. Gunshot Wounds
Legal Medicine
Penal Provisions of Law Relative to Firearm
• Alarms and Scandals ( Art. 155, RPC)
• Discharge of Firearms ( Art 254, RPC)
Small Firearms
Those which will propel projectile of less than one inch in diameter.
Types of Small Firearms of Medico- Legal Interest
• Revolver
• Automatic Rifle
• Rifle
• Shotgun

4. Gunshot Wounds
Legal Medicine
Two principal component parts of a weapon in order to cause an
injury are:
• Cartridge or Ammunition
• The Firearm
Principal Parts of the Cartridge
• The Cartridge case or shell
• Primer
• Powder or propellant
• Bullet or projectile

5. Gunshot Wounds
Legal Medicine
Important parts of a Firearm
• The trigger with a firing pin
• The Barrel
Things Coming Out of the Gun Muzzle After the Fire
• Bullet
• Flame
• Heated, compressed and expanded gas
• Residues coming from
Bullet
Powder Particles
Primer
Barrel
Cartridge case

6. Gunshot Wounds
Legal Medicine
Destructive Mechanism of Gunshot
1. Laceration and Permanent Cavity in the Bullet Trajectory
2. Temporary Cavity
3. Hydrostatic Force
4. Shock Wave
5. Fragmentation or Disintegration of the Bullet
6. Fragmentation of Hard Brittle Object in the Trajectory
7. Muzzle Blast in Contact Fire
8. Other Consequential Effects on the Body of the Victim

7. Gunshot Wounds
Legal Medicine
Gunshot Wound of Entrance
The appearance of the gunshot wound of entrance
depends upon the following:
1. Caliber of the Wounding Weapon
2. Characteristic Inherent to the Wound of Entrance
3. Direction of the Fire
4. Shape and Composition of the Missile
5. Range
6. Kind of Weapon

8. Gunshot Wounds
Legal Medicine
Contact Fire:
The nature and extent of the injury is caused not only by the force of
the bullet but also by the gas of the muzzle blast and part of the body involved.
The following factors must be taken into consideration:
1. The effectiveness of the Sealing Between the Gun Muzzle and the Skin
2. The Amount if the Gas Liberated by the Combustion of the Propellant
3. Nature of Bullet
4. Part of the Body Involved
Pressed and Firm Contact Fire:
1. On Parts of the Body Where Bone is Superficial
2. Parts of the Body where the Bone is Deeply Located

9. Gunshot Wounds
Legal Medicine
Loose Contact or Near Fire:
1. Entrance wound may be large circular or oval depending upon
the angle of approach of the bullet.
2. Abrasion collar or ring is distinct
3. Smuggling, burning and tattooing are prominent with singeing
od the hair
4. Muzzle imprint may be seen depending upon the degree of
slapping of the skin of the gun muzzle
5. There is blackening of the bullet tract to a certain depth
6. Carboxyhemoglobin is present in the wound “ and sorrounding
areas.

10. Gunshot Wounds
Legal Medicine
Short Range Fire ( 1to 15 cm distance)
1. Edges of the entrance wound is inverted
2. If within the flame reach there is an area of burning
3. Smudging, burning and tattooing is present
4. Abrasion ring or collar is present.
Medium Range Fire ( more than 15 cm. but less than 60 cm.)
1. Gunshot wound with inverted edges and with abrasion collar is
present.
2. Burning effects is absent.
3. Smudging may be present if less than 30 cm. distance.
4. Gunpowder tattooing is present but of lesser density and has a
wider area of distribution.
5. Contact ring is present.

11. Gunshot Wounds
Legal Medicine
Fired More than 60 cm. Distance
1. Gunshot wound is circular or oval depending on the angle of
approach with abrasion collar.
2. Wound of entrance has no burning, smudging or tattooing.
3. Contract ring is present.
Instances When Size of the Wound of Entrance Do Not
approximate the Caliber of the Firearm
In distant fire, the rule is that the diameter of the gunshot
wound of entrance is almost the same as the caliber of the
wounding firearm, but in the following instances, the following rule
is not followed:
1. Factors which make the wound of entrance bigger than the
caliber: a. In contact or near fire

12. Gunshot Wounds
Legal Medicine
b. Deformity of the bullet which entered.
c. Bullet might have entered the skin sidewise
d. Acute angular approach of the bullet
2. Factors which make the wound of entrance smaller than the
caliber:
a. Fragmentation of the bullet before penetrating the skin
b. Contraction of the elastic tissues of the skin
In shotgun fire, the size of the wound of the entrance is
dependent upon the distance of the fire. Near fire causes
concentration of entry of the pellets, and as distance increases the
pellets disperse with individual pellets causing individual wounds
of entry. Only in this instance may the wound of entrance of the
same size as the gauge of the shotgun pellets.

13. Gunshot Wounds
Legal Medicine
Evidences or Findings Used to Determine Entrance of Gunshot:
When the course of the bullet is through and through and
there is a difficulty in the determination as to which is the entrance
because it does not show characteristic findings, or it has been
modified by healing, infection or surgical intervention, the medical
examiner must resort to the following:
1. Examination of the clothing, if involved in the course of the
bullet
2. Examination of the internal injuries caused by the bullet
3. Testimony of the Witnesses

14. Gunshot Wounds
Legal Medicine
Determination of the Trajectory of the Bullet Inside the Body of the
Victim:
1. External Examination
a. Shape of the Wound of Entrance
b. Shape and Distribution of the Contusion or Abrasion
Collar
c. Difference in Level Between the entrance and exit
wounds
d. By probing the wound entrance
2. Internal Examination
a. Actual dissection
b. Fracture of Bones and course in visceral organs
c. Location of bone fragmentation and lead particles
d. X-ray Examination

15. Gunshot Wounds
Legal Medicine
3. Other Evidences to show Trajectory
a. Relative difference in the vertical location of the entrance
from the exit in the clothing.
b. Relative position and distance of the assailant from the
victim in the reconstruction or reenactment of the crime.
c. Testimony of witnesses.
Exit ( Outshoot ) Wound
An exit wound does not show characteristic shape unlike
the wound of entrance. This is due to the absence of external
support beyond the skin so the bullet tends to tear or shatter in the
skin while sufficient amount of kinetic energy is still in the bullet
during the process of piercing the skin.

16. Gunshot Wounds
Legal Medicine
Distinction between Gunshot Wound of Entrance and Wound of
Exit: Entrance Wound Exit Wound
Appears to be smaller than the missile
owing to the elasticity of the tissue
Always bigger than the missile
Edges are inverted Edge are everted
Usually oval or round depending upon
the angle of approach of the bullet
It does not manifest any definite shape
“ Contusion collar” or “ Contact ring” is
present, due to invagination of the skin
and spinning of the of the missile
“Contusion collar” is absent
Tattooing or smudging may be present
when firing is near
Always absent
Underlying tissues are not protruding Underlying tissues may be seen
protruding from the wound
Always present after fire May be absent, if missile is lodged in the
body
Paraffin test may be positive Paraffin test always negative

17. Gunshot Wounds
Legal Medicine
The “ Odd and Even Rule” in Gunshot Wounds:
If the number of gunshot wounds of entrance and exit
found in the body of the victim is even, the presumption is that no
bullet is lodged in the body, but if the number of the gunshot
wounds of entrance and exit is odd, the presumption is that one or
more bullets might have been lodged in the body.
How to determine the number of fires made by the Offender:
1. Determination of the Number of Spent Shells.
2. Determination of Entrance Wounds in the body of the victim.
3. Number of shots heard by witnesses

18. Gunshot Wounds
Legal Medicine
Instances when the number of gunshot wounds of entrance is less
than the number of gunshot wounds of exit in the body of the
victim:
1. A bullet might have entered the body but split into several
fragments, each of which made a separate exit.
2. One of the bullets might have entered a natural orifice of the
body.
3. There might be two or more bullets which entered the body
through a common entrance and later making individual exit
wounds.
4. In near shot with a shotgun, the pellets might have entered in a
common wound and later dispersed while inside the body and
making separate wounds of exit.

19. Gunshot Wounds
Legal Medicine
Instances when there is no gunshot wound of exit but the bullet is
not found in the body of the victim:
1. When the bullet is lodged in the gastro-intestinal tract and
expelled through the bowel, or lodged in the pharynx and
expelled through the mouth by coughing.
2. Near fire with a blank cartridge produced a wound of entrance
but no slug may be recovered.
3. The bullet may enter the wound of entarance and upon hitting
the bone the course is deflected to have the wound of
entrance as the wound of exit.

20. Gunshot Wounds
Legal Medicine
Problems confronting Forensic Physician in the Identification of
Gunshot Wounds:
1. Alteration of the Lesion Due to Natural Process
2. Medical and Surgical Intervention
3. Embalming
4. Problem Inherent to the Injury Itself
5. X-ray Examination

21. Gunshot Wounds
Legal Medicine
Evidences that tend to show that the Gunshot(s) Wound is
suicidal:
1. The shot was fired in a closed or locked room, usually in the
office or bedroom.
2. The death weapon is almost always found near the place
where the victim was found.
3. The shot was fired with the muzzle of the gun in contact with
the part of the body involved or at close range.
4. The location of the gunshot wound of entrance is in an
accessible part of the body to the wounding hand.
5. The shot is usually solitary.
6. The direction of the fire is compatible with the usual trajectory
of th bullet considering the hand used and the part of the body
involved.
7. Personal history may reveal social, economic, business or

22. Gunshot Wounds
Legal Medicine
Evidences that tend to show that the Gunshot(s) Wound is
suicidal:
8. Examination of the hand of the victim may show presence of
gunpowder.
9. Entrance wound do not usually involve clothing.
10. Fingerprints of victim on the butt.
11. Search of the place where the shot took place may reveal a
suicide note which usually mentions.
12. No disturbance in the place of death.
Evidences that tend to show that the Gunshot(s) Wound is
homicidal:
1. The site or sites of wound of entrance has no point of election.
2. The fire is made when the victim is usually at some distance

23. Gunshot Wounds
Legal Medicine
Evidences that tend to show that the Gunshot(s) Wound is
homicidal:
3. Signs of struggle may be present in the victim.
4. There may be a disturbance of the surroundings on account of
previous struggle.
5. Wounding firearm usually is not found at the scene of the crime.
6. Testimony of witnesses.
Evidences that tend to show that the Gunshot(s) Wound is
accidental:
1. Usually there is but one shot.
2. There is no special area of the body involved.
3. Consideration of the testimony of the assailant and
determination as to whether it is possible to be accidental by
knowing the relative position of the victim and the assailant.

24. Gunshot Wounds
Legal Medicine
Shotgun Wounds:
A shotgun is a shoulder- fires firearm having
a barrel that is smooth bored and is intended for a
charged compound of one or more round balls or
pellets.
Classes of Shot in a Shotgun Shell:
1. Birdshot
2. Buckshot
3. Single Projectile ( Rifled Slug)

25. Gunshot Wounds
Legal Medicine
Shotgun Wounds of Entrance:
1. Contact or Near Contact Shot ( not more than 6”)
2. Long Range Shot ( more then 6” skin muzzle distance)
Determination of the Presence of Gunpowder and Primer
Components
Procedure in determining the presence of gunpowder:
1. Gross examination or examination with the use of hand lens.
2. Microscopic examination.
3. Chemical Test.

26. Gunshot Wounds
Legal Medicine
Tests for presence of powder residues:
1. On the skin :
Dermal nitrate Test – the back of the fingers and of the
hand up to the region of the wrist is coated with melted paraffin,
heated at a temperature of 150 degree Fahrenheit. Test is no
conclusive as to the presence of gunpowder.
2. On clothing ( especially colored one)
Walker’s test ( C- acid test, H- acid test)- a glossy
photographic paper is fixed thoroughly in hyposolution for 20
mins. to remove all the silver salts and then washed for 45 mins.
and dried.

27. Gunshot Wounds
Legal Medicine
Tests for presence of primer components:
1. Harrison and Gilroy Test
2. Neutron Activation Analysis ( NAA)
3. Flameless Atomic Absorption Spectroscopy ( FAAS )
4. Use of scanning electron microscope with a linked x-ray
analyzer:
Firearm Identification
1. Caliber of the Weapon
2. Fingerprints
3. Fouling of the Barrel
4. Serial Number

28. Gunshot Wounds
Legal Medicine
Gunshot Wounds in Different Parts of the Body
 Head and Neck:
1. Cranium
2. Brain Substance
3. Face
4. Neck
 Chest:
1. Chest Wall
2. Lungs
3. Heart

29. Gunshot Wounds
Legal Medicine
Gunshot Wounds in Different Parts of the Body
 Abdomen
 Spine and Spinal Cord
 Extremities