Sitting Bull

When the muzzle is held near the skin, but not actually in contact with it, a number of helpful signs are produced. Once again the appearance is naturally modified by clothing, which must always be carefully preserved and subjected to forensic scientific examination. Where clothing is present, then it will trap most, but not necessarily all, of the soot and powder grains. It will reduce the flame effects, though if the fabric is ignited even momentarily, this can diffusely scorch the skin. Assuming that the body surface is uncovered, a close discharge - one between actual contact and about 15 cm (6 inches) - is likely to show the following features:

-          Singeing of hairs around the wound, unless the skin is hairless. The fine downy hairs of the trunk and limbs may be burnt away, though this is unlikely with dense, long, head hair. Where the distance is greater, the keratin of the hair may melt with the flame and then solid on cooling, causing a 'clubbed' appearance of the hairs because of rounded bulges at the tips.

-          Burning of the skin, unless protected by head hair. There may be a wide flare or narrow rim of hyperaemia or even blistering from the flame of incandescent gas blown from the muzzle.

-          The tissues within and around the wound may be cherry-pink from absorption of carbon monoxide.

-          There will be 'smoke soiling' or 'soot staining' of the skin, from carbon deposition. This spreads more widely than powder tattooing, but does not carry as far as the heavier propellant grains. This effect is much less or even absent with modern 'clean' propellants. This soot or smoke soiling is easily washed off the dun, and care must be taken at autopsy to obtain all photographs and trace samples before allowing the bloodstains to be washed from the body. Tattooing will not wash off, though adherent unburnt propellant may be physically detached from the tiny burns during any washing or swabbing process.

-          Burning, partly burnt and unburnt propellant flakes and grains may  pepper the surrounding of the wound. As stated above, these carry further than smoke staining, but usually spread over a smaller area. The incandescent particles cause small burns on the skin, but the unburnt flakes (such as nitrocellulose) may be seen as small glistening particles on the skin, sometimes coloured.

-        The wound will be circular if the weapon is held at right angles to the skin and elliptical if slanted, often with undercut edges on one side. Depending partly on the size of the pellets, 'nibbling' or crenation of the edge may be seen, though this is usually imperceptible as buttons or buckles being hurled against the skin by the gas pressure.

-          Any felt or cardboard wads or plastic cups from the cartridge will be within the depths of the wound.

From about 15 cm (6 inches) to 2 m (6 feet), considerable variation occurs in the appearance of the wound. The shorter range will provide a similar picture to that of close discharge, but the soot soiling diminishes and over 20-40cm it may vanish. Powder tattooing near the wound periphery may persist for somewhat further than this. At the upper end of this range the edges of the wound will become crenated and scalloped, especially with larger shot. This is sometimes called the 'rat-hole' or 'rat-nibbling' from its resemblance to rodent teeth marks. From 2 m upwards, the number of satellite pellet holes will progressively increase around the main wound. It must be emphasized that these are useful generalizations, but that marked variations occur between different weapons, different barrels of the same weapon and different ammunition fired from the same gun. Only test firing can give a measure of the length of the flame, the distance and pattern of soot staining and powder tattooing, the beginning of pellet spreading and the distance over which the wads are projected. As a rough rule-of-thumb, which is often incorrect, hair singeing occurs over the first 30cm (1 foot), soot staining can be seen for the first half-metre (20 inches) and a single large hole persists for at least 1 m (3 feet).

Test firing is even more vital for an estimate of range, as the variation is great. The choke as opposed to cylinder barrel on the same gun will provide different appearances at the same range. Once beyond 2 m, there will be no burning or smoke staining, rarely will there be powder tattooing and the presence of the wads will be variable. Sometimes the latter fall away within 2 m, but they can sometimes be found in a wound up to 5 m distant. Often the wad takes a lower trajectory and may strike the body below the shotgun wound. It may penetrate the skin, causing a second lacerated wound or it may only bruise the skin. Some of the plastic cup devices now used open up in flight to form a square-edged star or capital 'X' shape. This can strike the skin at or near the shotgun wound and produce a characteristic bruise or abrasion of a similar shape. The spread of pellets, which usually begins at a metre or two range, increases progressively, the central 'rat-hole' diminishing at the same rate.

There is an old (and extremely inaccurate) rule-of-thumb which states that the diameter of the spread in inches is roughly equal to the range in yards (metric: one-third of the spread in centimetres equals the range in metres). This of course applies to a circular wound or the narrow diameter of an oblique elliptical wound; it is of no use other than a quick first check to indicate if suicide can be excluded, but expert examination and test-firing are essential. At distant ranges, beyond 6-10 meters, the central hole may shrink to nothing. There will naturally be no wad injuries, no smoke, flame or tattooing, and no way of determining range except to say that it must be within the maximum discharge distance of that particular weapon, which may be 30-50 m. At such ranges the shot will not be lethal and the pellets, if they penetrate the skin, will lie just in the subcutaneous tissues. Death may occur, however, from an unlucky shot in the eye or from natural disease precipitated by pain and shock.

It has already been stated that, where the discharge has been at right angles to the body surface, the shape of the wound will be symmetrical and circular. A shotgun blast traces out a shallow cone from the muzzle and simple geometry demands that where this cone intersects a plane (the skin), a circle will result only when the cone is at 90" to the plane. In all other positions an ellipse will be traced out, its elongation increasing as the angle between them decreases. This pattern applies not only to the pellet spread but to soot deposition and pro- vides a ready indication of the direction:

- The wound edges may be shelved, the tissues being undercut below the margin distal to the origin of the discharge. The appearances are similar to those seen in some knife wounds, where an oblique stab leaves tissue visible at one edge and undercut on the other. In firearm wounds this is better seen in injuries from a single rifled projectile than from the more diffuse mass of shotgun pellets, but is still sometimes apparent in the latter.

- The track of the wound in the deep tissues can be established and this line projected backwards to indicate the discharge direction relative to the body. Again, a missile from a rifled weapon usually gives a clearer picture than those from a shotgun, but a general estimate can be obtained from a knowledge of the positions of the surface wound and the mass of pellets. Examination of a radiograph may be of more assistance that the laborious search from pellets at autopsy. Whatever the type of missile(s), considerable deviation caused by deflection by bone and other tissues can occur, so that the final resting place of the projectile may be far off the initial track. Thus the actual path through the tissues before ricochet must be established, if possible.

Exit wounds are uncommon in the trunk as the energy possessed by each pellet is small because of its tiny size and the relatively low muzzle velocity of the weapon. The 'four-ten' will almost never exit and even the twelve-bore rarely causes a through-and-through wound of the adult chest or abdomen. The pellets often penetrate the distal chest wall, but are held up beneath the skin of the further side of the trunk. Commonly a bruise may be seen in the deep tissues of the frustrated exit site and lead shot may be felt under the skin, which is tough enough to prevent the final exit phase. In the head, neck and limbs, and in children and small thin adults, the twelve-bore commonly causes an exit wound which may be extremely large and ragged, with gross tissue destruction exposed. One of the most common is that seen when a twelve-bore is discharged suicidally into the mouth; this may disrupt the head, and expel most of the brain through a massive skull and scalp defect - the so-called 'burst head'.

The internal track is more diffuse than that caused by a rifled weapon, though where the discharge is contact or close, the compacted mass of shot travels as a unit for some distance into the tissues before dispersing. In general, the internal damage caused by a shotgun is diffuse and is caused by direct mechanical disruption by the gas and shot, which enter at relatively low velocity. There is no cavitation effect as is seen in high-velocity injuries, the tissue being physically smashed by the impact of a heavy load of pellets and, in the case of near discharges, by the large volume of hot propellant gases. Secondary damage is caused by the mass of pellets striking bone and releasing fragments that then act as secondary missiles, damaging adjacent tissues and sometimes emerging to form exit wounds. These may sometimes cause confusion to inexperienced observers, including police officers, who may wrongly suspect multiple shots or the use of some other type of weapon. Wad wounds can be caused by the non-metallic contents of a shotgun cartridge. These can vary from trivial bruises to fatal lacerations. The latter may occur when a blank cartridge is discharged at close range, the wad and accompanying gas breaching the body surface.

Beyond a metre or two, the wad may drop suficiently to miss the main wound and strike the skin at a lower point. From 2 to 5 m, the wads may or may not strike the body, and further than this distance it is almost certain that the wads will fall to the ground. As with all variables associated with firearm wounds, however, it is essential for test firing to be performed wherever possible.

Tangential wounds can offer considerable dificulry in - recognition to the inexperienced observer. Some pathologists, as well as clinicians and police officers, have attributed certain wounds to knives or blunt injuries, when in fact they have been gunshot wounds. The shallow cone of a shotgun discharge may pass any part of the body so that the central axis is clear of the tissues, but the periphery strikes the body surface tangentially. The most common position is probably the side of the chest, in the lower axilla. If the arm is raised it may escape damage, but sometimes an opposing injury is seen on the chest wall and inner part of the upper arm. Another area is the side of the face, where a glancing gun blast may gouge the face and perhaps carry away an ear.

The appearance of the wound depends, of course, on the range and the depth to which the cone of shot and gas penetrates. On the side of the chest, a large elliptical area may be ripped from the surface to expose underlying muscle and ribs. If a close discharge, then the nature of the injury will be clear from the usual burning and soiling of the muzzle gases, but a more distant shot may cause a clean wound that can give rise to doubt about causation. Radiography will usually reveal lead shot in the tissues, unless the contact is extremely superficial. 

The lateral transfer of energy can cause severe internal damage in both chest and skull, even though the missile does not enter the cavities. The skull may be extensively fractured, with widespread underlying damage, and in the absence of any projectile and a deficient knowledge of the circumstances, some such injuries have erroneously been ascribed to blunt trauma.  

Acknowledgements:

www.aived.nl    AIVD – @Erik Akerboom ©

 

www.politie.nl  Politiekorpschef  @Janny Knol©

 

www.politie.nl WEB Politie - @Henk van Essen©

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