forensic pathology gunshot wounds. gsw are penetrating or perforating gsw are penetrating or...

FORENSIC FORENSIC PATHOLOGYPATHOLOGY

GUNSHOT WOUNDSGUNSHOT WOUNDS


GSW are penetrating or GSW are penetrating or perforatingperforating– Penetrating = bullet enters an object Penetrating = bullet enters an object

but does not exitbut does not exit– Perforating = bullet passes through Perforating = bullet passes through

and exits objectand exits object


Many things follow the bullet Many things follow the bullet upon leaving the barrelupon leaving the barrel– Partially burned powderPartially burned powder– Particles of bullet metalParticles of bullet metal– SootSoot– Bullet lubricantBullet lubricant– Inorganic elements from primerInorganic elements from primer


Gunpowder exits the muzzle in Gunpowder exits the muzzle in two forms two forms – Completely burned powder is called Completely burned powder is called

soot or fowlingsoot or fowling– Burning and unburned particles are Burning and unburned particles are

referred to as stippling or powdered referred to as stippling or powdered tattooingtattooing Particles will travel farther than the soot Particles will travel farther than the soot

and will abrade the skinand will abrade the skin


SootSoot– Carbon powder which contains Carbon powder which contains

vaporized metals from primer, bullet vaporized metals from primer, bullet and cartridge caseand cartridge case

– As range from muzzle to target As range from muzzle to target increases, size of zone of powder increases, size of zone of powder soot blackening will increasesoot blackening will increase

– Density of blackened soot Density of blackened soot decreasesdecreases


Placement of soot can vary due toPlacement of soot can vary due to– RangeRange– PropellantPropellant– Angle of muzzle to targetAngle of muzzle to target– Barrel lengthBarrel length– Caliber of weaponCaliber of weapon– Type of weaponType of weapon– Target material and state of target (blood Target material and state of target (blood

or not)or not)


SootSoot– Barrel lengthBarrel length

Longer barrel produces smaller and Longer barrel produces smaller and more dense soot patternsmore dense soot patterns

Handguns deposit soot out to 30 cmHandguns deposit soot out to 30 cm

– Orientation of muzzleOrientation of muzzle Muzzle at 90 degree angle = circular Muzzle at 90 degree angle = circular

shape with hole in centershape with hole in center Muzzle at 2cm + angle = blossom Muzzle at 2cm + angle = blossom

shape with eccentric holeshape with eccentric hole


Gunshot Wound Residue is Gunshot Wound Residue is deposited in zonesdeposited in zones– Zone I = Contact GSWZone I = Contact GSW

Muzzle of weapon held against body Muzzle of weapon held against body surfacesurface

– Wound may be classified as hard, loose, Wound may be classified as hard, loose, angled or incompleteangled or incomplete

– Edges may be seared by gases and blackened Edges may be seared by gases and blackened by soot and propellantby soot and propellant

With or without seared blackened zone With or without seared blackened zone around woundaround wound


Zone I - Hard Contact WoundsZone I - Hard Contact Wounds– Muzzle of weapon is jammed “hard” against Muzzle of weapon is jammed “hard” against

skinskin Outside line of certain parts of the firearm may Outside line of certain parts of the firearm may

be imprinted in the skin be imprinted in the skin – Barrel, front sightsBarrel, front sights

– Skin is indented by weaponSkin is indented by weapon– Edges of wound are seared by hot gases of Edges of wound are seared by hot gases of

combusted and blackened sootcombusted and blackened soot Soot may be embedded in seared skinSoot may be embedded in seared skin Cannot wash soot out of woundCannot wash soot out of wound


Zone II – LooseZone II – Loose– approx. 0- 4 inches away from bodyapprox. 0- 4 inches away from body– Intense, dark sooting with dense Intense, dark sooting with dense

deposits of unburned and partially deposits of unburned and partially burned powder around bullet holeburned powder around bullet hole

– Destruction of clothing and skin Destruction of clothing and skin possiblepossible


Zone II = Loose ContactZone II = Loose Contact– Muzzle in contact with skin, but held Muzzle in contact with skin, but held

lightly against surfacelightly against surface– Gas from weapon forms gap Gas from weapon forms gap

between gun and woundbetween gun and wound– Soot is deposited around entrance Soot is deposited around entrance

woundwound– Soot can be wiped awaySoot can be wiped away


Zone II = Angled Contact WoundZone II = Angled Contact Wound– Muzzle is held at an angle to the skinMuzzle is held at an angle to the skin– Gas and soot radiate outward from muzzleGas and soot radiate outward from muzzle– Soot is found in two different zonesSoot is found in two different zones

Most noticeable zone – Blackened seared area Most noticeable zone – Blackened seared area of skin or cloth, having a pear, circular or oval of skin or cloth, having a pear, circular or oval shapeshape

Second zone – large fan-shaped zone of light Second zone – large fan-shaped zone of light gray soot radiating from gapgray soot radiating from gap

Soot can be washed awaySoot can be washed away


Zone II – Angled Contact WoundsZone II – Angled Contact Wounds– Eccentric seared blackened zone of Eccentric seared blackened zone of

skin on opposite side of wound from skin on opposite side of wound from muzzle pointing the way the gun muzzle pointing the way the gun was directedwas directed

– Wound widest on side opposite Wound widest on side opposite muzzlemuzzle

– Larger eccentric zone of soot Larger eccentric zone of soot depositiondeposition


Zone II – Angled Contact WoundsZone II – Angled Contact Wounds– If the angle between the barrel and If the angle between the barrel and

skin decreases, the gap between skin decreases, the gap between muzzle and skin is largermuzzle and skin is larger More material can escape through the gapMore material can escape through the gap Unburned grains of powder may sear skinUnburned grains of powder may sear skin

– Angled contact wounds can have Angled contact wounds can have powder tattooing on opposite side of powder tattooing on opposite side of wound from muzzlewound from muzzle


Zone II – Incomplete Contact Zone II – Incomplete Contact WoundsWounds– Muzzle of weapon is held against the Muzzle of weapon is held against the

skin, there is a gap between muzzle skin, there is a gap between muzzle and skinand skin Soot escapes through gapSoot escapes through gap Seared or blackened skin located Seared or blackened skin located

adjacent to woundadjacent to wound– Most often seen in suicidesMost often seen in suicides


Zone III – Near Zone III – Near – Approximately 4 – 6 inches from Approximately 4 – 6 inches from

bodybody– Medium to light gray sootingMedium to light gray sooting– Circular pattern of powder Circular pattern of powder

distribution around bullet holedistribution around bullet hole– Tattooing possibleTattooing possible


Zone IV – Intermediate Range WoundsZone IV – Intermediate Range Wounds– Approximately 6 – 24 inches from bodyApproximately 6 – 24 inches from body– No visible sootingNo visible sooting– Dispersed powder particlesDispersed powder particles

As soon as one sees individual tattooing marks, As soon as one sees individual tattooing marks, one is dealing with intermediate range woundsone is dealing with intermediate range wounds

Near wounds may be seared zone, but no Near wounds may be seared zone, but no individual tattoo marksindividual tattoo marks


Zone IV – IntermediateZone IV – Intermediate– TattooingTattooing

Reddish-brown to orange-red punctate Reddish-brown to orange-red punctate lesions around wound entrancelesions around wound entrance

Skin on same side of barrel (at angle) Skin on same side of barrel (at angle) will have dense tattooingwill have dense tattooing

Powder tattooing occurs antemortemPowder tattooing occurs antemortem– Postmortem tattooing marks are gray or Postmortem tattooing marks are gray or

yellow in coloryellow in color


Zone IV – Intermediate Range Zone IV – Intermediate Range WoundsWounds

Powder tattooing is due to impact Powder tattooing is due to impact of powder grains on skin – Not of powder grains on skin – Not powder burnspowder burns

Punctate abrasions cannot be Punctate abrasions cannot be wiped awaywiped away


Zone V: Distant Range WoundsZone V: Distant Range Wounds Approximately 2-3 feet or Approximately 2-3 feet or

greatergreater– The only marks on the body are The only marks on the body are

those produced by mechanical those produced by mechanical action of bullet perforating the skinaction of bullet perforating the skin


RevolversRevolvers– Gas, soot and powder emerge from muzzle Gas, soot and powder emerge from muzzle

and gap between cylinder and barreland gap between cylinder and barrel If weapon is parallel to body soot from cylinder-If weapon is parallel to body soot from cylinder-

barrel gap produces a L- or V-shaped patternbarrel gap produces a L- or V-shaped pattern If weapon is at an acute angel to body, searing If weapon is at an acute angel to body, searing

will occur a distance from entrance woundwill occur a distance from entrance wound– Can measure barrel lengthCan measure barrel length


Muzzle BrakeMuzzle Brake– Redirects gases at muzzle to generate a Redirects gases at muzzle to generate a

forward thrust on muzzle and counters forward thrust on muzzle and counters force of recoilforce of recoil

Flash SuppressorFlash Suppressor– Breaks up the “fireball”Breaks up the “fireball”– Cylinder with longitudinal slits along its Cylinder with longitudinal slits along its

lengthlength– Gases emerges through the slits instead of Gases emerges through the slits instead of

out muzzleout muzzle

forensic pathology gunshot wounds. gsw are penetrating or perforating gsw are penetrating or...

Documents

blackened zone of skin

powder soot blackening

skin barrel

seared area of skin

woundgunshot woundszone

size of zone

awaygunshot woundszone

skin decreases