REVOLVER
1. location of the empty shells –
revolve r the empty shells are found in the cylindri cal magazi ne chamb er after the fire 2. nature of the spent shell – automatic firearm = bullet is copper jackete d 3. nature of the base of the cartridge or
spent shell = base of a revolve r has a wider diamet er than that of the cylindri cal body to keep the cartrid ge stay in the magazi ne chamb er. It may be possible for a person who is accustomed to the sounds of firearms of different calibers to identify the firearm by the sound produced.
It is not possible to determine the direction of the shot by determining the direction of the sound except when the flash or the person firing the shot is seen at the time the shot was fired. GSW may not be a near fire or may not appear to be near fire:
1. when a device is set up to hold the firearm and to enable it to be discharged at a long range by the victim.
2. when the GSW of entrance does not show characteristics of a near shot bec the clothing are interposed bet. the victim & the firearm
3. when the examining physician failed to distinguish between a near or far shot wound
4. when the product of a near shot has been washed out of the wound. X-ray
1. facilitate the location and extraction of the wound
2. reveals fragmentation and its location 3. shows bone involvement like fracture 4. reveal trajectory of the bullet
5. shows effect of the bullet wound, like hemorrhage, escape of air, laceration SHOTGUN WOUNDS
Is a shoulder fired firearm having a barrel that is smooth-bored and is intended for the firing of a changed compound of one or more balls or pellets.
Measure the distance between the two farthest shot(pellets) in inches and subtract one, the number obtained will give the muzzle-target distance in yards. Determination of the presence of
gunpowder and primer components: Importance:
1. Determination of the distance of the gun muzzle from the victim’s body when fired. Usually not more than 24 inches when fired.
2. Determining whether a person has fired a firearm. – dorsum of the hand
= metallic residues, burning and unburned gunpowder
= in suicide found in the palm
Procedures in determining the presence of gunpowder:
1. Gross examination use of hand lens – Fine black powder – not conclusive
2. Microscopic examination 3. Chemical test:
1. On the skin – Dorsum of the hand or Wound of entrance
Dermal nitrate test ( Paraffin test, Diphenylamine test, Lung’s test, Gonzales’ test)
= melted paraffin heated at 150 degrees fahrenheit – Lung’s reagent
= small particles with nitrate or nitrite > blue reaction
= not conclusive: fertilizers, cosmetics, cigarettes, urine
= Negative is not conclusive: thorough washing
2. On clothings
Walker’s test ( C-acid test, H- acid test)
= glossy photographic paper fixed in hyposolution for 20 min to remove the silver salts &washed for 45 min. & dries
Tests for the presence of Primer
Components – metallic primer residues like barium, antimony, and lead.
1. Harrison and Gilroy test :Cotton swab moistened with 0.1 molar HCl to gather the primer component.
= Reagent sodium rhodisonate yields red color with the primer components.
= Add 1.5 HCl to the red area> blue-violet or pink in lead or barium
= lacks specificity, sensitivity
2. Neutron Activation Analysis (NAA) = Sample obtained by paraffin or by washing with dilute acid
= Extremely sensitive, even with small quantity
3. Flameless Atomic Absorption Spectroscopy (FAAS)
4. Use of Scanning electron
microscope with a Linked X-ray analyzer THERMAL INJURIES OR DEATHS
- are those caused by deviation from normal temperature, capable of producing cellular or tissue changes in the body.
- Exposure to severe cold = Frost bite - exposure to high temperature = burning scalding
1. DEATH OR INJURY FROM COLD - not common in the Philippines - Primary cause of death: Decrease dissociation of O2 from Hgb in the RBC
: Diminished power of the tissue to utilize O2
- Cold damp air is more fatal than cold dry air. - Women are more resistant to cold > greater deposits of SQ fats.
Effects of COLD:
A. Local effect ( Frostbite, Immersion foot, Trench foot )
1st – Blanching , paleness of the skin due to vascular spasm.
2nd – Erthyma, edema, swelling due to vascular dilatation, paralysis and increased capillary permeability. 3rd - Blister formation
4th – Necrosis, vascular occlusion, thrombosis and gangrene.
Microscopically: Vacuolization, degeneration of epidermal cells
: Necrosis of the collage of the SQ tissue
: Occlusion of the vessels due to clumping of RBC
B. Systemic effects:
- Reflex in nature due to the stimulation and paralysis of the nerves
- Pulmonary ,Cardiac action is slowed down due to cerebral anoxia> resulting to lethargy, delirium, convulsions, coma/ death.
2. DEATH OR INJURY FROM HEAT – effect may be local or general
Classifications of Heat Injury: a) General or Systemic effects:
a.1 Heat cramps a.2 Heat exhaustion a.3 Heat stroke b) Local effects: b.1 Scalding b.2 Burns = Thermal = Chemical = Electrical, lightning = Radiation
GENERAL OR SYSTEMIC EFFECT: death usually accidental
1. Heat cramps( Miner’s Camp, Firemans Camp, Stroker’s camp)
- Involuntary spasmodic painful contraction of muscles due to dehydration and excessive loss of chlorides by sweating
- Tx: Fluids with chlorides
2. Heat Exhaustion ( Heat collapse, Syncopal Fever, Heat syncope, Heat prostration)
- Due to heart failure, cause:Heat precipitated by exertion/warm clothes
= Sudden syncope, face turns pale, dim vision
3. Heat stroke(Sunstroke,Heat
Hyperpyrexia,Comatous form,Thermic Fever)
- Working in ill-ventilated places with dry temperature or exposure to the sun
LOCAL EFFECTS OF HEAT