Other minor signs of a wound inflicted during life may be briefly mentioned. If the edges of the wound are swollen, or show signs of inflammation or gangrene, or if pus or adhesive material is present on the edges of the wound, we may infer that the wound was inflicted some little time before death. Of course, if cicatrization has commenced, some days must have elapsed before death after the wound was received. If the blow causing a contusion was inflicted some time before death, there will be more or less of a general swelling of the region, partly due to the blood effused, but also partly due to œdema.
It is not always easy to say whether a fracture was produced while the body was living or dead. If the body was still warm when a post-mortem fracture was produced there is little difference from an ante-mortem fracture, except that there may be a little less blood effused. In a fracture produced after rigor mortis has set in there is little or no blood effused. In the case of fractures the presence of callus, indicating the process of repair, shows that the accident occurred during life, and, as we have already seen, we may form some idea of the length of time elapsed between the injury and the time of death. On the cadaver it is said to be harder to cause fractures and lesions of the skin than on the living body. Casper says that fractures of the hyoid bone and the larynx are impossible after death, and he also was not able to rupture the liver or spleen.
In distinction to the characteristic signs of a wound inflicted during life, we may mention briefly some of the signs of post-mortem wounds when the wound has been inflicted from two to ten or twelve hours or more after death:
(1) The hemorrhage is slight in amount and may fail altogether.
(2) The character of the hemorrhage is venous, corresponding to the source of the hemorrhage from the veins, the arteries being nearly empty after death.
(3) The edges of the wound are not deeply stained, and this staining may be removed by washing. The spaces between the tissues are not infiltrated with blood.
(4) The blood remains either entirely fluid or, if there are clots, these are softer than those in an ante-mortem wound, and only a portion of the blood is thus clotted. There are no clots plugging the open mouths of the arteries on the surface of the wound; the veins may or may not be closed by an imperfect clot.
(5) The skin of the edges is not everted or inverted.
(6) The sides of the wound do not gape and their surfaces are smooth and even, as the tissues are not unevenly retracted.
Résumé.—It is very easy from the foregoing to distinguish between a wound inflicted before death and one ten or twelve hours after death.
If the hemorrhage has been abundant and arterial, if it has infiltrated between and deeply stained the tissues and the stain cannot readily be washed off; if the blood coagulates completely and the coagula are firm and are found lying in the wound, plugging the vessels, and incorporated with the tissues between which they lie; if the edges of the skin are everted and the sides of the wound are retracted and uneven—under these circumstances, we may be sure that the wound was inflicted during life or a very short time after death. If, on the contrary, the hemorrhage is slight in amount or almost fails altogether; if it is venous in character; if the edges of the wound are only stained by imbibition of the blood, which is not infiltrated between the tissues, and the stain may be washed off; if the blood is not at all or only slightly clotted and the clots are soft; if the skin is not everted and the sides of the wound are smooth and lie nearly in contact; if there are no clots plugging the divided arteries on the surface—then we need have little hesitancy in saying that the wound was produced after death, but probably not later than ten or twelve hours after death. If the wound was inflicted still longer after death and before putrefaction, then we would have a lack of the signs due to hemorrhage, clots, staining, etc. If we find the conditions more or less midway between the first two, we may be left in some doubt as to the date of the injury. Thus if the hemorrhage is moderate, the blood mostly but not altogether clotted and the clots moderately firm, the skin slightly everted, and the sides slightly separated and not altogether smooth on their surface; if the surfaces are fairly deeply stained and the stain cannot be easily washed off—then we can only say that the wound was inflicted during life or within two hours or so after death, and this fact is often enough for the purposes of the medico-legal inquiry.
The same is the case with contusions where there is no bleeding externally. If we have a bluish, violet, green, or yellow tumor with or without more or less superficial œdema; if this tumor fluctuates or is hard, but in either case is elastic; if on incision the skin and the tissue spaces are infiltrated with blood which is coagulated, or if there is a cavity filled with clotted blood, the coagulum being firm and the entire amount of blood coagulated—then the wound was inflicted during life. If, however, the surface shows a bluish or violet color, little or no swelling of the skin, which is of natural thickness, and the ecchymosed area is not tense and elastic to the touch; if further the blood is found on incision to be fluid or if coagulated only partly so, and the blood is not infiltrated into the tissue spaces, but merely imbibed by the tissues—then the blow was inflicted after death, and probably more than two or three hours after.
In contusions especially we may have difficulty, as the sign of fluidity of the blood may fail and putrefaction may modify the conditions of the wound unless parts deep beneath the surface be examined.
We see, then, that in some cases it is very easy to say that a wound was inflicted post mortem. If a wound was not inflicted until ten or twelve hours after death or even sooner, we cannot easily mistake it. But in many cases it may be hard or impossible to say whether a wound was inflicted during life or within an hour or two after death. Here we must be cautious in expressing an opinion which should be guarded. But we should remember that it is important to be able to state that a wound was inflicted before or immediately after death, as no one but a murderer would think of inflicting a fatal injury on a body immediately after death. In such cases a well-guarded medical opinion may often meet all the requirements of the case.
Granted that a given wound was produced before death. There are, then, one or two questions which may arise, and which depend for their answer on the length of time the wounded person could have lived and the physiological or muscular acts which he could have performed after receiving the injury and before death. The first of these questions may be expressed as follows:
Could the Victim have Performed Certain Acts after having Received his Fatal Injury? The term “certain acts” here refers to almost any thing or things which would require time and strength—in other words, the continuance of life with bodily and mental powers for a certain time after receiving a mortal injury.
This question may be raised in relation to an attempted alibi of the accused, who may have been proved to be in the presence of the victim a moment before death. If after this moment the victim has moved from the spot or performed certain acts before death, the attempted alibi may depend upon the answer to the question as to whether the given acts of the victim were compatible with the fatal character of the wound. An alibi can aid in the acquittal of the accused only when the nature of the injury was such that death would be supposed to be immediate or nearly so. Great care should be taken on the part of the medical witness in answering this question, for after very grave wounds, proving speedily fatal, the victim sometimes can do certain acts requiring more or less prolonged effort, as shown by numerous examples. Wounds of the brain are especially noticeable in allowing a survival of several hours, days, or even weeks, during which time the injured person may pursue his occupations. Where the survival has lasted days or weeks, the alibi has no importance, but not if the survival is of shorter duration. The following case is cited by Vibert[1] and may be mentioned in this connection, though the wound was caused by a bullet which traversed from behind forward the entire left lobe of the brain. After the injury the victim was seen by several witnesses to climb a ladder, though with difficulty, for he had right-sided hemiplegia. He was found insensible more than half a mile away, and did not die until six or eight hours after the injury. Severe injury of important organs is sometimes not incompatible with an unexpectedly long survival. Devergie cites two illustrations of this which are quoted by Vibert.[622] A man received several extensive fractures of the skull, with abundant subdural hemorrhage, and rupture of the diaphragm with hernia of the stomach. The stomach was ruptured, and nearly a litre of its contents was contained in the left pleural cavity. Notwithstanding all this, he was able to walk about for an hour or so and answer several questions. He died only after several hours. Another man, crushed by a carriage, received a large rupture of the diaphragm, complete rupture of the jejunum, and rupture and crushing of one kidney. Yet he walked nearly five miles, and did not die until the next day.
More rarely wounds of the great vessels are not immediately fatal. M. Tourdes is quoted by Vibert[623] as citing the case of a man who descended a flight of stairs and took several steps after division of the carotid artery; also of one who lived ten minutes after a bullet-wound of the inferior vena-cava.
Even wounds of the heart are not as speedily fatal as is commonly supposed, and often permit of a comparatively long survival.
Fischer[624] found only 104 cases of immediate death among 452 cases of wounds of the heart, and healing occurred in 50 cases among 401. Vibert[625] mentions two striking cases of long survival after wounds of the heart. A woman received a stab-wound which perforated the right ventricle, causing a wound one centimetre long. She did not die until twelve days later, when on autopsy there was found an enormous extravasation of blood in the left pleural cavity and pericardium. The second case, though one of bullet-wound, is equally applicable and instructive in this connection. A man received a bullet-wound which perforated the left ventricle, the bullet being found later in the pericardium. After being wounded he threw a lamp at his assassin which set fire to the room. He then went into the court-yard, drew some water, carried it back in a bucket, extinguished the fire, and then lay down on his bed and died.
In studying the wounds of different regions of the body, we may find many other mortal wounds which, though speedily fatal, leave the possibility of more or less activity before death. We see, therefore, that even in those wounds which are commonly supposed to be immediately fatal, even by many medical men where attention has not been called to the exceptions, such exceptional cases are not uncommon in which death is not immediate. Time and even strength may thus be allowed for more or less complicated activity. An alibi cannot, therefore, be allowed without question on the part of the medical expert, who must exercise great caution in expressing an opinion. The second question which may sometimes arise in connection with the last, but having little to do with the subject of this section, is the following:
How Long before Death had the Deceased Accomplished Certain Physiological Acts? For instance, how long after a meal did he die? This is hard to answer with precision, as digestion varies with the individual, and digestion begun during life may go on to a certain extent after death. We may be able to say if digestion has just commenced, is well advanced, or has terminated. What was eaten at the last meal may be learned by the naked eye, the microscope, the color of stomach contents and their odor. The state of the bladder and rectum is sometimes called in question. All the above facts have less bearing on the case than those in relation to the former question.
The cause of death should be certain and definite. In reality, there is only one real cause, though one or many circumstances may be accessory causes. In most cases of death from the class of wounds which we have been considering, there is no difficulty in determining the cause of death so as to be able to state it definitely. But if the deceased had recovered from the first effects of the wound and then died, or if death seems as much due to disease as to injury, then the real cause of death may be obscure. If the medical witness is in doubt as to which of two causes was the primary cause of death the doubt should be stated at once, as it may weaken the testimony if brought out later.
Wounds may be directly or indirectly fatal. They are directly fatal if the victim dies at once or very soon after the wound, with no other cause internally in his body or externally from his environment. Wounds are indirectly or secondarily fatal if the injured person dies from a wound disease or complication, the direct consequence of the wound, or from a surgical operation necessary in the treatment of the case. Wounds may also be necessarily fatal either directly or secondarily, or not necessarily fatal. In the latter case death may be due as much, if not more, to other causes than the wound, and sometimes not at all to the wound itself. Thus death may be due to natural causes, latent disease, an unhealthy state of the body, imprudence or neglect of treatment, or improper treatment, etc. These various degrees of responsibility of a wound as the cause of death we will now consider more at length.
If so, it must have caused death in one of the following ways:
1. Hemorrhage.—This may act by producing syncope. But the amount of the hemorrhage may not be sufficient for this result, and still cause death by disturbing the function of the organ into which it is effused, as in the brain or in the pleural or pericardial cavities. The blood here acts mechanically. Blood in the trachea may also kill mechanically by causing asphyxia.
The amount of hemorrhage required to produce syncope varies under a variety of circumstances. Less is required in the very young, the aged, and the diseased, also less in women than in men. Young infants may die from hemorrhage from very slight wounds, even from the application of a leech or the lancing of the gums. A sudden loss of blood is much more serious than an equal amount lost slowly. This is the reason that the wound of an artery is more serious and more rapidly fatal than a similar loss of blood from other sources. It is hard to specify the absolute quantity which must be lost in order to cause death by syncope. The total blood in the body is about one-thirteenth of the weight of the body, making the total amount of blood weigh about twelve pounds. Of this, about one-fourth is in the heart, lungs, and large blood-vessels. According to Watson, the loss of an amount varying from five to eight pounds is enough to be fatal to an adult. But less is enough to prove fatal in many cases, as the rapidity of the loss of blood and the age, sex, and bodily condition of the wounded person affect the amount necessary. Though death from a small artery is slower than that from a large one, yet it may occur in time, as shown in the instance quoted by Taylor,[626] where a man bled to death in thirty-eight hours from the wound of an intercostal artery. Thus, too, a wound of the branches of the external carotid artery is often enough to cause death, and a wound in a vascular part may cause death from hemorrhage, though no vessel of any size be divided.
Internal hemorrhage may be fatal from mechanical interference with the function of an organ, as well as from syncope. Thus we may have death from syncope due to hemorrhage into the peritoneal cavity or, after contusions, into the intercellular spaces and the cavity due to the blow, into which several pounds of blood may be extravasated. Internal hemorrhage is most fatal when due to the rupture of a viscus such as the heart, lungs, liver, kidney. Taylor[627] cites a case of a man run over and brought to Guy’s Hospital in November, 1864. He had pain in the back, but there were no symptoms or marks of severe injury. He left the hospital and walked home, where he was found dead in bed a few hours later. His abdomen contained a large amount of blood from the rupture of a kidney. After severe flagellation blood may be effused in large quantity beneath the skin and between the muscles, which is just as fatal as if it had flowed externally from a wound. In fact, if the injuries are numerous the loss of much less blood is enough to prove fatal, the element of shock here assisting that of hemorrhage.
How are we to ascertain whether a person has died from hemorrhage? This may be more difficult in the case of an open wound, for the body may have been moved from the spot where it lay after the wound was received, and the blood on the body, clothes, and surrounding objects may have been removed. Then the case may be presumptive only, but we may arrive at a definite conclusion by attention to the following points: If the wound was in a very vascular part and of some size, or if a large vessel or many moderately large vessels were divided and the vessels, especially the veins in the neighborhood, are empty, then we may be quite sure of death from hemorrhage. If there is no disease found which could be rapidly fatal the case is still stronger. The body should be pallid after fatal hemorrhage, but the same may be the case from death from other causes. In case the body and surrounding objects have not been disturbed, then the amount of clotted blood in the wound, on the body and clothes, and about the body, taken in connection with the foregoing points, can leave no doubt. We should remember, however, that not all the blood about the body was necessarily effused during life, but a little hemorrhage may have occurred after death while the body was still warm and the blood fluid, i.e., during the first four, eight, or ten hours. But the amount thus lost is small. In cases of death from internal hemorrhage we do not have so much difficulty in pronouncing an opinion, as by post-mortem examination we can determine the amount of the hemorrhage. We can judge, too, from its position, whether it has acted mechanically to interfere with a vital function, and has thus caused death, or whether the latter was due to syncope from the quantity lost.
2. Severe mechanical injury of a vital organ, such as crushing of the heart, lungs, brain, etc. This crushing may be accompanied by hemorrhage, but death may be more immediate than the hemorrhage would account for. The mechanical injury done to the vital centres in the medulla by the act of pithing is the direct cause of the sudden death which follows it. Exceptionally slight violence to a vital organ is fatal, but this may be better explained by attributing it to shock.
3. Shock.—An injury is often apparently not enough to account for the fatal result so speedily. The marks of external injury may fail entirely or be very trifling. Thus more than once persons have died in railway collisions with no external marks of violence. So, too, a blow on the upper abdomen, on the “pit of the stomach,” has been rapidly fatal without any visible injury to the viscera. Death is attributed to the effect on the cardiac plexus, and there may be no marks externally or only very superficial ones. In Reg. v. Slane and Others (Durham Wint. Ass., 1872), quoted by Taylor,[628] the deceased was proved to have sustained severe injuries to the abdomen by kicks, etc., but there were no marks of bruises. All organs were found healthy on post-mortem examination, but the injured man died in twenty minutes. Death was attributed to shock and the prisoners were convicted of murder.
Death from concussion of the brain is another example of death from shock. This may occur with only a bruise on the scalp and with no intracranial hemorrhage or laceration of the brain. The medical witness should be cautious in the above classes of cases in giving evidence, as the defence may rely upon the absence of any visible signs of mortal injury to prove that no injury was done, a principle fundamentally wrong.
Also a number of injuries, no one of which alone could be the direct cause of death, may cause death on the spot or very soon afterward. Death in such cases, where there is no large effusion under the skin, is referred to exhaustion, which, however, is merely another term for shock. Such cases are exemplified by prize-fighters who, during or after the fight, become collapsed and die of exhaustion. Having sustained numerous blows on the body during the many rounds, the body presents the marks of various bruises, but there may be nothing else to explain the sudden death. No one injury or bruise is mortal, and yet, when the deceased was previously sound and in good health, death must be referred directly to the multiple injuries received in the fight. We have already stated above that if the injuries are numerous, the loss of a smaller amount of blood may be fatal. We see, therefore, that there is not always a specific and visible “mortal” injury to account for death. This is a well-known medical fact, but it does not accord with the erroneous popular prejudice that no one can die from violence without some one visible wound which is mortal. In other words, the non-professional mind leaves out of account the idea of shock, only regarding material injury and not functional disturbance. If the circumstances accompanying death are unknown, it is well to be cautious. But if the deceased was in ordinary health and vigor and there was no morbid cause to account for the sudden death, we need not hesitate to refer death to the multiple injuries.
This brings up a number of interesting questions to be considered. In medical jurisprudence there is probably no condition so common as that the injury is admitted, but death is attributed to some other cause. Thus if there are several wounds it may be hard to decide on the relative degree of mortality of any particular one, so as to be able to say that death was directly or necessarily due to this or that one. The defence may plead that death was not necessarily due to the particular wound attributed to the prisoner. This brings up the question—
Which of two or more Wounds was the Cause of Death? No general rule can be laid down for all cases, but each case must be judged by itself. Another way of putting the question is: “Which of two or more wounds was mortal?” The questions are not quite synonymous, for two or more of the wounds might be “mortal” but not equally the cause of death. In fact, as we have already seen, no one of the wounds if they are multiple may be of itself mortal, but taken together they are so. Consequently we will suppose that there are but two wounds, and not multiple ones, and the question remains which of these wounds was the cause of death. A wound may be said to be of itself mortal when it is the cause of death directly or indirectly in spite of the best medical assistance. In some continental states mortal wounds are divided into two classes, those absolutely and those conditionally mortal, the former including those in which the best medical assistance is at hand, sent for or timely rendered without everting the result. The mortal result in the second class is conditional on want of treatment, improper treatment, or accidental circumstances. As Taylor says, it is better to look at the effect of the wound and the intent of the assailant, as is done in English law, rather than at accidental relations of the wound.
To return to the question, we can readily imagine that a man may receive two wounds at different times or from different persons, and die after the second wound. Taylor[629] mentions the following case in which the question arose as to which of two injuries caused death: In Reg. v. Foreman (C.C.C. February, 1873) the prisoner had struck the deceased some severe blows on the head. A fortnight later, having partially recovered, another man gave him some severe blows on the head. A fortnight later still he had left hemiplegia, and died a few days later of a large abscess in the brain. The question arose which set of blows had been the cause of the abscess. The prisoner, the first assailant, was acquitted, as the deceased had had no serious symptoms until the second assault, and there was no satisfactory medical evidence as to the relation of the two assaults to the abscess formation. The same author also supposes the following case: A man having received a gunshot wound of the shoulder is doing well, when in another quarrel he receives a penetrating stab-wound of the thorax and abdomen. He dies after lingering for a time, under the effects of these wounds. If the wound of the shoulder could be proven to be the cause of death, the second assailant could not be convicted of manslaughter, and so too with the first assailant if it could be shown that the victim died of the stab-wound. It might be possible for a surgeon to decide the question definitely at once if death occurred soon after the stab, which was found to have penetrated the heart, a large blood-vessel, or one of the viscera; or, on the other hand, if the stab-wound was found to be superficial and not penetrating, and the wound in the shoulder had suppurated and caused septicæmia.
In either or any case, everything would depend upon the evidence furnished by the medical witness. His knowledge and judgment are required to distinguish the guilty from the innocent.
Again, sometimes death may appear to be equally the result of either or both wounds, in which case, as far as the medical evidence goes, both assailants would be liable to the charge of manslaughter. Or the second wound may be accidental or suicidal, and again the question would arise as to the cause of death. A case illustrating this is told by Taylor[630] substantially as follows: A grocer’s assistant pursued a thief, who had stolen from a cart, into a coal-shed, where he was stabbed twice in the abdomen. The larger wound suppurated, the smaller wound healed up, and the man died of peritonitis. On post-mortem examination the suppurating wound was found not to involve a vital part, while the small healed wound had wounded the liver and gall bladder and had set up the fatal peritonitis. The large suppurating wound had apparently been inflicted purposely; the fatal wound, directed upward and backward, might have been accidental by the deceased rushing upon the knife held more or less in self-defence. The case never came to trial, as the assailant was never found, but it can be readily imagined what complications might have arisen.
Furthermore, the wounded person may have taken poison or been subsequently ill-treated, and he may have died from these causes rather than the injury. But the question arises as to whether the wound was necessarily the cause of death. Here, in order to exculpate the assailant, the supervening disease or maltreatment must be such as to account for sudden or rapid death under the symptoms which actually preceded death.
Was Death Due to Natural Causes? Again, the injury may be admitted, but it may be claimed that death is due to natural causes. It is not unusual for wounded persons to die from natural causes, though the case may appear otherwise to laymen. This is often seen with suicidal wounds, especially those inflicted during the delirium of a disease, or the disease may supervene later and cause death without relation to the wound. Where the wound was inflicted by another, accurate discrimination is especially important in order to save the accused from imprisonment under false accusation and consequent loss of character. A careful examination is the only way to determine such cases, which depend therefore on the medical testimony.
Again, the question may arise as between DEATH FROM WOUNDS OR LATENT DISEASE, the wound perhaps being admitted, but death being attributed to latent disease. Here a close attention to symptoms and a careful post-mortem examination can alone decide. A man may die from the rupture of an aneurism, from an apoplexy or some other morbid condition after receiving a severe wound. Or a man with a hernia may receive a blow upon it causing a rupture of the contained intestine followed by peritonitis and death, or the recipient of a blow may have a calculus in the kidney which may perforate a blood-vessel or the kidney tissue and set up a fatal hemorrhage as the result of a blow.
Thus, medically speaking, the result of the injury is unusual and unexpected, and due to an abnormal or unhealthy state of body of the wounded person.
If it can be clearly shown by the medical testimony that death was due to the above or any other latent diseases, the responsibility of the assailant may be lessened or removed. The law looks to this point and is lenient in its punishment in the absence of malice on the part of the assailant. The crime is still manslaughter and may even be murder if the assailant was actuated by malice and the abnormal or unhealthy state of the body of the victim was taken advantage of. Generally there is no intention of murder, but the nature of the wound and the means of infliction will help to show this, which is for the jury rather than the medical witness to decide. There is less ground for mitigation of the punishment if the assailant was aware of the peculiar condition of the wounded person, especially in the case of those notoriously ill or of pregnant women.
Closely allied with this subject are those rare cases where ABNORMAL ANATOMICAL CONDITIONS, such as a thin skull or brittle bones, cause a slight injury to be followed by unexpected and untoward results, not to be looked for in the average individual. In such cases the evidence of the abnormal condition furnished by the medical witness may diminish the responsibility and mitigate the punishment.
Furthermore, the responsibility of the assailant may not be altogether removed, for the question naturally arises, Was death accelerated by the wound? This depends upon the circumstances in each case upon which the medical witness must base his opinion. Maliciously accelerating the death of another is regarded as criminal on the principle that that which accelerates causes. The following cases are quoted from Taylor[631] to illustrate the above distinctions. In Reg. v. Timms (Oxford Lent Ass., 1870) the deceased had been struck on the head by the accused with a hatchet, from which injury he had partly recovered under treatment in twelve days. But six weeks later he was seized with inflammation of the brain, with convulsions, and died. At the autopsy disease of the kidneys was found, and death was referred to this and the inflammation of the brain due to the blows. The prisoner was convicted after the judge had charged the jury that it was manslaughter if they believed that the blows conduced in part to the death of the deceased.
In the following cases there was no connection between the violence and the cause of death. A man struck his father on the head with a hammer and was sentenced to two months’ imprisonment, as the injury did not appear serious. The father thought the punishment too little, became much excited, and was hemiplegic six days after the wound was inflicted and died three days later. No injury of the brain was found under a fracture of the inner table at the site of the blow, but a large clot was found in the lateral ventricle which, in the opinion of the medical witnesses, was not dependent on the blow, and the prisoner was acquitted (see Reg. v. Saxon, Lancashire Sum. Ass., 1884). Also in Reg. v. Hodgson (Leeds Sum. Ass., 1876) the prisoner had struck his wife with a belt, a short time after which she fell back and died suddenly. The cause of death was found to be heart disease, and the blow not being causative in producing the fatal result, the prisoner was acquitted. Or again in Reg. v. Thompson (Liverpool Sum. Ass., 1876): The prisoner had stabbed his wife in the cheek. The wound was severe but not mortal. Two days later she was delivered of a child in the infirmary to which she was taken. She died nine days later of puerperal fever. The prisoner was acquitted on the charge of murder, as there was no necessary connection between the wound and the puerperal fever. Acquittals have taken place in cases of death occasioned by terror or dread of impending danger produced by acts of violence, as in the case of Reg. v. Heany (Gloucester Lent Ass., 1875). Here the prisoner in an altercation with his wife, who was suffering from cancer, held up a knife in a threatening manner, but did not touch her. This gave her a shock; she died two days later from fright. As there was no distinct proof that death was accelerated by this act, the prisoner was acquitted of the charge of murder. Taylor[632] found among a large number of cases occurring in England during twenty years that the latent causes of death, as registered in wounded persons, were chiefly inflammation of the thoracic or abdominal viscera, apoplexy, diseases of the heart and large blood-vessels, phthisis, ruptures of the stomach and bowels from disease, internal strangulation, and the rupture of deep-seated abscesses. Sometimes the person was in good health up to the time of injury, while in other cases there was merely a slight indisposition. It was only by carefulness on the part of the medical experts that the true cause of death was ascertained.
Again, it may be claimed that DEATH was not necessarily the result of the wound and was AVOIDABLE BY GOOD MEDICAL TREATMENT. There are many cases of wounds not mortal with proper and skilled treatment which might become so by improper treatment. They may thus become directly mortal by interfering with a source of hemorrhage which had been arrested, or secondarily mortal by infection of the wound by meddlesome treatment. It would depend on the medical witnesses to determine whether and how far the treatment had been responsible for the fatal result. If the wound is not of itself mortal and it has only become so from improper treatment, this should be a mitigating circumstance in favor of the accused. Medically speaking, we can seldom make the sharp distinction which Lord Hale did legally between a wound becoming mortal from improper treatment and one in which improper treatment causes death irrespective of the wound. In case of a slight wound this distinction might be possible, but not so in case of severe wounds. Also there would probably be no conviction, as far as the medical evidence is concerned, if the wound was only mortal in consequence of improper treatment and not mortal as its usual and probable result. This may naturally introduce the question of the COMPARATIVE SKILL IN TREATMENT. If death is entirely or partly due to a wound the responsibility of an assailant is not altered by unskilful treatment. The entire question of the relation of the wound to the fatal result and the effect on this result of the treatment employed is left to be determined by the medical experts, and in its solution great care and judgment must be used. Although a given fatal wound might not have caused death under the best possible treatment and surroundings, yet, according to the above rule, the assailant is held responsible as long as the fatal result is due partly, at least, to the wound. Therefore we see the responsibility of the surgeon not only for the life of his patient, but also for that of the prisoner. He should, therefore, not deviate from the ordinary and most accepted practice in such cases, as any such deviation is taken hold of by the counsel for the defence. In fact, every point of the treatment is subjected to criticism.
In a lacerated wound of the foot, if death occurs from tetanus, it may be claimed that death would not have occurred if the foot had been amputated, or, if the foot were amputated and death followed, it may be claimed that amputation was unnecessary and was the cause of death. The surgeon should, therefore, be able to give the best reasons for every step of treatment.
Again, it may be claimed that DEATH was not a necessary result of the wound and WAS AVOIDABLE BUT FOR IMPRUDENCE OR NEGLECT on the part of the wounded person. A man after being wounded may refuse to receive medical assistance, or, after receiving it, may disobey instructions or refuse to submit to an operation proposed. Thus with a compound depressed fracture of the skull the patient may either refuse to see a surgeon, or he may refuse to submit to an operation proposed, or he may with or without operation disobey the instructions as to diet and quiet, and eat or drink heavily and refuse to go to bed. Such a case we can readily imagine might die of meningitis, etc.
If the symptoms of a wound are unfavorable from the start, or if the wound of itself is likely to prove mortal, the responsibility of the assailant is unmitigated by imprudence or neglect of medical assistance by the wounded person. This is not allowed as mitigatory, as a sane man is a free agent and is not obliged to call in or submit to medical treatment. Moreover, a medical witness in many cases could not swear that an operation or other plan of treatment would certainly save life. Thus an amputation of the leg for wound of the foot causing tetanus is by no means a certain means of cure. But we can readily imagine a case where the refusal to submit to the treatment proposed might be an important element in causing death. Thus in a compound depressed fracture of the skull with compression, the medical witnesses would agree that the operation would in all probability save life. This fact would probably be only mitigatory in diminishing the penalty, and, as stated above, would not secure acquittal. But it is none the less important for the medical witness to bear these facts in mind and bring out the facts and conclusions clearly in his testimony.
Death Following Slight Personal Injuries.—Here again the claim might apparently be justified that death was not necessarily due to the trifling injury. And in reality there is commonly some unhealthy state of the body to explain such an unexpected result. When the disease accounting for this unhealthy state of the body is in some other part than the injury, an examination with ordinary care will explain the case. But if the disease and injury are located in the same part, especially in the head, the case is more perplexing, but may be cleared up by careful and thorough examination. Also the usual results of such an injury should be considered, and whether the disease would be a usual result of the injury, or whether the sum total of the pathological conditions found would be accounted for by the violence. It should be remembered that the presence of chronic disease is no excuse. Thus Taylor[633] cites the case of Reg. v. Hapley (Lewes Aut. Ass., 1860), where a boy with chronic disease of the brain suffered from no unusual symptom until he received a severe flogging, which was followed by death in less than three hours. The same author mentions also the following case to show that fatal results may follow very slight and trivial blows. Annan[634] tells of a healthy four-year-old girl who received a slight blow from the shaft of a wheelbarrow on the skin about three inches below the knee. There was even no external mark of violence, and the injury was thought to be so slight as not to require treatment. There was pain, however, which increased on the following day, marked constitutional symptoms appeared, and the child died on the fourth day. Even to the punishment inflicted by schoolmasters death has been imputed.
When DEATH occurs FROM WOUNDS AFTER LONG PERIODS the injury may be admitted, but it may be claimed that death was not necessarily due to the wound. Medically speaking, death is just as much the result of the injury as if it occurred on the spot. Of course, death must be clearly traceable to the usual and probable results of the injury, and not be dependent on any other cause. An examination of the wounded part and of the whole body will enable the medical witness to determine the cause of death and whether it is clearly traceable to the injury. A doubt on this point may lead to acquittal. Certain forms of wounds or wounds in certain localities are especially liable to end fatally after a long delay, but as the direct result of the wound. These are wounds of the head and of the spine. As to the first class, the injured person may apparently recover and be doing well, when he may suddenly die from a cerebral abscess, for instance. This is the result of the injury, but remains a longer or shorter time latent. In wounds of the spine the patient is generally paralyzed below the point of fracture, but is apparently in good health. In a longer or shorter time he may die of a pneumonia, cystitis, or bedsores, which are the known and regular consequences of the injury or injured condition. Astley Cooper cites the case of a man who was injured on the head and died two years later from the effects of the injury, as was clearly made out by the continuance of brain symptoms during the entire period. An interval of eleven years occurred in another head injury between the injury and the fatal result. The first result of the injury was concussion of the brain, and the case is mentioned by Hoffbauer.[635] This long interval is unusual. There is a rule in English law by which the assailant cannot be indicted for murder if the victim of the assault lives a year and a day. Practically this makes little difference, as nearly all cases would die within that time; but the principle is wrong as looked at from the medical standpoint. The protracted cases concern, as above stated, mostly injuries of the head, spine, and chest, among which there are some cases, like the examples cited, where, according to English law, justice would fail to be done.
A wound is secondarily the cause of death when the victim, having recovered from the first ill effects, dies from some wound disease or accident or from a surgical operation rendered necessary in the proper treatment of the wound. There may be much difficulty in establishing the proof of death from a wound by means of secondary causes, for, 1st, the secondary cause must be in the natural course of things; and, 2d, there must be no other accidental circumstances to occasion the secondary cause.
The secondary cause may be partly due to the constitution of the deceased from habits of dissipation, which fact would serve as an expiatory circumstance in the case. Among the secondary causes of death may be mentioned septicæmia, pyæmia, erysipelas, tetanus, gangrene, that is, wound diseases, also the wound accident—as we may call delirium tremens, and surgical operations rendered necessary to the treatment of the case. We may add, besides the regular wound diseases, inflammation in and about the wound, septic in character, perhaps not justifying the title of septicæmia, but which, with its accompanying fever, may be the “last straw” in a case which might otherwise recover. Some of these secondary causes will now be considered more at length.
Septicæmia is a general febrile disease due to the absorption into the system from a wound of the products of bacteria or due to the introduction into the blood and tissues of the bacteria themselves. Depending on the two sources of origin, we have two forms of septicæmia: 1. Septic intoxication or sapremia, due to the absorption of a chemical poison, ptomaïnes, and often readily influenced and cured by the removal of the source of these ptomaïnes in decomposing blood-clots, secretions, etc. 2. Septic infection comes on less rapidly but is more serious than the former is, if properly and quickly treated, because the source of the trouble cannot be removed, but is in the blood and the tissues. The latter form is the more common one in wounds, though the former may occur in abdominal wounds, especially when a blood-clot is present. The first form begins acutely, the second form more gradually. The infection in septicæmia takes place through a wound and may be due to the weapon which caused the wound, the unclean condition of the parts wounded, or to the subsequent treatment or want of treatment. It may even take place through the intestinal mucous membrane as in cases of tyrotoxicon poisoning. It is most likely to occur during the first four or five days before the surfaces of the wound granulate, and it consists in the introduction of bacteria, especially staphylococci and streptococci. The disease is characterized by severe constitutional symptoms, acute continuous fever, inflammation of certain viscera and of the wound, and nervous disorders. A pronounced chill ushering in the fever is generally absent. Prostration is especially marked, the patient finally passing into a typhoid condition indifferent to surroundings. Anorexia and headache are usually present; diarrhœa is common, vomiting is not. The skin is pale and dusky, but not commonly icteric; at first it is hot and dry, later moist and finally cold and clammy. The spleen is often enlarged. The pulse becomes weak and rapid and delirium is followed by coma. The prognosis is grave. Antiseptic treatment generally prevents and often cures the disease, as is the case with many other of the wound diseases; hence the failure to employ it may be alleged by the defence in mitigation of the responsibility of the assailant for the fatal result.
Pyæmia is closely allied to septicæmia. It is due to the setting free of bacterial emboli or septic emboli from a broken-down, septic thrombus in the neighborhood of the wound, and the circulation of these emboli in the blood until they are arrested and form the characteristic metastatic abscesses, especially in the lungs, joints, abdominal viscera, and parotid gland. Almost always the source of infection is an infected wound. Granulation does not prevent the occurrence of pyæmia, which, as a rule, commences at a later stage than septicæmia. It is most important, however, for our purpose to remember that there is such a thing as spontaneous pyæmia. An injury not causing a wound may here be the exciting cause, but the resulting pyæmia is an unexpected consequence. A bruise of a bone, for instance, by allowing bacteria, which in certain conditions may be circulating in the blood, to find an exit from the vessels into the bruised part, may develop an acute osteo-myelitis, which may be a starting-point of a pyæmia. It is but proper to state, however, that spontaneous pyæmia is a rare occurrence. In fact, it is so rare that if pyæmia occurs and we find ever so trifling an infected wound, we can safely attribute the pyæmia to the wound and not to a spontaneous origin.
Pyæmia begins, as a rule, in the second week of the healing process or even later. It usually begins with a chill, which may be frequently repeated. The fever is very irregular and exacerbations occur with each metastatic abscess. The skin is icteric, the icterus being hematogenous. The pulse is rapid and becomes weaker. Infective endocarditis may develop, which increases the danger of metastatic abscesses, which may then occur in the brain. Otherwise the mind is clear and unaffected until the final delirium and coma. The disease may become chronic, but usually lasts a week or ten days. The prognosis is very grave.
Erysipelas is a still more frequent complication of medico-legal wounds, and though not so fatal as the two preceding, it is probably more often the secondary cause of death on account of its far greater frequence. It too is an acute infective inflammation due to the presence of a micro-organism, streptococcus erysipelatis. This occurs mostly in the lymphatics of the skin, and effects an entrance through some wound or abrasion of the skin or mucous membrane, which may be almost microscopic in size. Probably there is no such thing as true spontaneous erysipelas, though the wound may be often overlooked and only visible on the closest examination. If a wound has been inflicted, the size and severity of it cannot be alleged as a reason why it was not the starting-point of an erysipelas. The erysipelas must be clearly traced to the injury. That is, it must occur before recovery from the wound or not later than a week after it has healed, for the incubation is probably not longer than this. It is difficult to connect an erysipelas with a wound if it occurs some time after it has healed or if it occurs at a different place and not about the wound. Wounds of certain regions, as, for instance, scalp wounds, are especially liable to develop erysipelas, but this is probably owing to the imperfect antiseptic treatment or delay in applying it. Certain individuals are more prone to it than others; thus it has been stated that blondes and those suffering from Bright’s disease are more susceptible, though how true this is it is hard to say. It is also probably more prevalent at certain times of the year, particularly in the spring. A wound after it has scabbed over or has begun to granulate, that is, after the first four or five days, is very much less apt to serve as the avenue for infection. Erysipelas usually begins with a chill, or a convulsion in children. Nausea and vomiting are the rule. The fever is remittent and ranges from 102° to 104° F., and the temperature may be subnormal when the inflammation is subsiding. Prostration is marked and the pulse more or less weak. There may be delirium while the fever is high. Locally there is rarely anything characteristic until twenty-four hours or so after the chill. Then we have a reddish blush with some tension, burning and itching of the skin. At first the redness is most marked about the wound, later at the edge of the advancing, serpentine margin. It spreads widely and rapidly, and after three or four days the part first attacked begins to improve. Desquamation follows. The duration may be a week or ten days or as long as a month. The inflammation may be much more severe, involving the subcutaneous connective tissue in phlegmonous erysipelas.
Facial erysipelas is a common variety and was once regarded as idiopathic, but a wound on the skin or mucous membrane is probably always present. The prognosis of erysipelas is usually favorable. Since the use of antiseptics it is far less common than formerly, though still the most common of the infective wound diseases.
If a man wounded in an assault is taken to a hospital where erysipelas prevails, the question of responsibility arises, for, medically speaking, he is subjected to great and avoidable risks.
Tetanus is an infective bacterial disease affecting chiefly the central nervous system and almost always, if not always, originating from a wound. Tetanus, like erysipelas, is probably always traumatic and never strictly idiopathic. The wound may be so slight as to escape notice. When it follows such injuries as simple fracture internal infection probably occurs, though such cases are extremely rare. It is said that the weather influences the development of tetanus, and that it is more common in the tropics. There are also certain sections where tetanus is much more common than elsewhere and where it may be said to be almost endemic. Punctured wounds are most likely to be followed by tetanus, for they offer the best opportunity for the development of the bacteria, which are anaërobic. Wounds in dirty parts of the body, like the hands and feet, are more apt to be followed by tetanus than those elsewhere. Tetanus usually appears about the end of the first week after a wound has been received, but it may not appear for a longer period, even three or four weeks, so that the wound may have been some time healed. To connect tetanus with a particular wound, note (1) if there were any symptoms of it before the wound or injury, (2) whether any other cause intervened after the wound or injury which would be likely to produce it, and (3) whether the deceased ever rallied from the effects of the injury. Tetanus comes on suddenly without warning. The injured person first notices that he cannot fully open the mouth, he has lock-jaw, and the back of the neck is stiff. The muscles of the abdomen and back are next involved so that the back is arched in the position known as opisthotonos, and the abdomen presents a board-like hardness. The muscles of the fauces, pharynx, and diaphragm may next become involved, causing difficulty in swallowing and breathing. The thighs may or may not be involved, but the arms and legs almost never. Owing to the spasm of the abdominal muscles, micturition and defecation are difficult and respiration is hindered. The muscles are in the condition of tonic spasm which permits the patient no rest, the face bears the “risus sardonicus,” and the suffering is extreme. If the patient lives more than two or three days the tonic spasm partly gives way to increased reflex irritability, in which a noise, jar, or draught of air may give rise to clonic and tonic spasms in the muscles affected. The patient may die at such times from tonic spasm of the respiratory muscles, or he may die of prostration from want of food and sleep, worn out by the suffering and muscular spasm. The mind is usually clear to the last. Fever is not characteristic of the disease. Tetanus may be rapidly fatal; in two or three days, or it may be or become more chronic. The prognosis of acute tetanus is almost invariably fatal; that of chronic tetanus is grave, but a certain proportion of cases recover.
Diagnosis.—This is easy. It differs from a true neuritis in the peripheral nerves in that no matter where the wound is situated the first symptom is in the muscles of the jaw and the back of the neck, and not at the site of the injury and distally from this point. Trismus is applied to a milder form of the disease in which only the face and neck muscles are involved and “lock-jaw” is a prominent symptom. Some cases of tetany may be mistaken for so-called spontaneous tetanus. Tetany may follow child-bed, fevers, mental shocks, exposure to cold and wet, extirpation of goitre, intestinal irritation, etc. It consists of painful tonic spasms of the muscles of the arms and feet. The attacks last one-half to two hours or more, and may be preceded by a dragging pain. They may be brought on by pressure on the nerve leading to the muscles affected. Striking the facial nerve often causes contraction of the face muscles. There is no trismus but there may be opisthotonos. The patient seems well between the attacks and most cases recover without treatment.
Delirium tremens may occur as a secondary consequence of injuries, or necessary surgical operations in the case of those who are habitually intemperate. Those who habitually use opium, tobacco, cannabis indica, or even tea or coffee to excess are said to be subject to it. It may, therefore, be justly alleged that death is avoidable in very many cases, but for an abnormal and unhealthy state of the body. The disease is characterized by delirium, a peculiar tremor of the muscles, insomnia, and anorexia. Pneumonia may complicate the case. The patients die in fatal cases from exhaustion due to insomnia, lack of nourishment, and their constant activity of body and mind. The prognosis is usually favorable, taking all cases together, but in delirium tremens secondary to surgical injuries or operations the prognosis is serious.
Death from surgical operations performed for the treatment of wounds. The operation is a part of the treatment, and if it is done with ordinary care and skill the accused is responsible for the result. The necessity and mode of operation must be left to the operator’s judgment. As the defence may turn on the necessity for and the skilful performance of the operation, it is well to wait for the advice and assistance of others if practicable, for death is not unusual from severe operations. The patient may die on the operating-table after losing little blood, from fear, pain, or shock. Or he may die from secondary hemorrhage or any of the secondary causes of death from wounds enumerated above. The evidence of the necessity of the operation must, therefore, be presented by the operator. If an operation is necessary and not performed, the defence might allege that death was due to the neglect of the surgeon. Another question for the medical witnesses to determine is whether the operation was rendered necessary because of improper previous treatment, for if it was the responsibility of the assailant may be influenced. The meaning of the term “necessity” is here a matter of importance. Unless an operation is necessary to the preservation of life, if death occurs there is some doubt whether the assailant is responsible. But, medically speaking, we would not hesitate to urge an operation on a wounded man in order to preserve function, or even to save deformity as well as to save life. In the case of operations done under a mistaken opinion, neither necessary to save life nor, as the result proves, to save function or guard against deformity, if death follows the assailant may be relieved from responsibility. Thus an aneurism following an injury might be mistaken for an abscess and opened with skill but with a fatal result. It is also for the medical experts to determine whether an operation was unnecessary or unskilfully performed, for if it were and death resulted from it, the responsibility of the prisoner is affected unless the original wound would be likely to be fatal without operation. According to Lord Hale, if death results from an unskilful operation and not from the wound, the prisoner is not responsible. But yet death may occur as the result of the most skilful operation necessary to the treatment of a wound, and not be dependent at all on the wound itself. If the operation is skilfully performed, and yet the patient dies from secondary causes, such as those above enumerated or any others, the prisoner is still responsible, and the medical testimony is concerned with the performance of the operation and the secondary causes of death. The relative skill of the operator or surgeon is probably not a question for the jury in criminal cases, on the ground that the man who inflicts the injury must take all the consequences, good or bad. In a civil suit, for instance an action for malpractice, the case is otherwise, and all the medical facts and opinions are submitted to the jury. The law regards three circumstances in death after surgical operations: (1) The necessity of the operation, (2) the competence of the operator, and (3) whether the wound would be fatal without operation.
Death may occur from anæsthetics used in an operation without any recognizable contributing disease of the patient, or carelessness or lack of skill in the administration of the anæsthetic. Of course, the question of absence of contributing disease on the part of the patient and of its proper administration must be satisfactorily answered in cases of death from the anæsthetic in an operation rendered necessary in the treatment of a wound. Death from an anæsthetic may occur before, during, or after an operation itself. Medically speaking, the necessity of the use of an anæsthetic in operations cannot be questioned, and in emergencies where an operation becomes necessary, and not a matter of choice, its use, with special care, is justifiable even with existing organic disease, which usually contraindicates it. As death may be alleged to be due to the use of a particular anæsthetic, it is always best in operating on account of an injury which may require a medico-legal investigation, to use that anæsthetic which is most generally used and indorsed in the particular section of country in question. Of course, it is not lawful to operate against the will of a person who preserves consciousness and will. It may be added in this connection that if a medical man be guilty of misconduct, arising either from gross ignorance or criminal inattention, whereby the patient dies, he is guilty of manslaughter, according to Lord Ellenborough. Omissions or errors in judgment, to which all are liable, are not criminal.
It is not often necessary to prove that a weapon was used, though it may affect the punishment. For the use of a weapon implies malice and intention and a greater desire to do injury. The prisoner may swear that no weapon was used when the nature of the wound clearly proves that one was used. The explanation of the prisoner of the origin of the wound may thus be discredited. We cannot often swear that a particular weapon was used, but only that the wound was made by one similar to it in shape and size. Thus Schwörer tells of the case of a man stabbed in the face by another. The medical witness testified that the wound was caused by a knife shown at the trial which had a whole blade, but a year later the point of the knife which had really caused the wound was discharged from an abscess in the cheek at the site of the wound. The surgeon thus made a too definite statement in regard to the knife shown.
It is often very difficult to answer the above question. We base our opinion chiefly on two sources: 1st, and most important, by an examination of the wound, and, 2d, by an examination of the instrument said to have been used. Certain particulars of the wound may furnish indications as to the weight, form, and sharpness of the instrument used. There are certain wounds which must have been made by an instrument, namely, incised and punctured wounds. The above question is determined more or less by what has been said in a former section on wounds, but we will now consider what special features of these and other classes of wounds indicate the nature, shape, size, etc., of the weapon used.
Incised wounds must be made by a cutting instrument. We would here exclude those contused wounds of the scalp and eyebrows which closely resemble incised wounds, but we have already seen that we can diagnose between these wounds and incised wounds by careful inspection. But the locality should put us on our guard, so that in case of wounds of these two regions we should be especially careful in making the examination.
In the case of incised wounds we cannot often tell the shape or size of the weapon, but we are able to tell certain characteristics about it. The sharpness of the instrument may be inferred from the clean and regular edges. The depth of the wound may also indicate the sharpness of the weapon. A long “tail” in the wound indicates that the weapon was sharp as well as that this was the part of the wound last made. If the edges of the wound are rough, we may infer that the edges of the weapon were rough and irregular. Wounds caused by bits of china or glass or fragments of bottles, besides having rough and lacerated edges, are characterized by an irregular or angular course in the skin.
Some cutting weapons, like an axe, act as much by means of their weight as by their cutting edges. Wounds caused by such weapons we can often distinguish by the following signs: The edges are not as smooth as is the case with a cutting instrument, and they may be more or less lacerated and show signs of contusion. The wound is often deep in comparison with its length, and the ends of the wound abrupt instead of slanting up from the bottom to the surface. The section of resisting organs and the impression of the edge of the weapon on the bone are further signs of the use of such a weapon.
The form and direction of a wound may possibly give some indication of the form of the instrument—for instance, whether it be straight or curved like a pruning-knife, as in the case cited by Vibert[636] of a wound of the neck which suddenly became deeper toward its extremity and changed its direction; the whole being explained on the supposition that it was made by a pruning-knife.
But it is in punctured wounds especially that we are enabled most often and most accurately to determine the kind of a weapon used. Here from the form of the wound we may judge of the form and size of the weapon. In speaking of punctured wounds in a former section we divided them into four groups, reference to which may here be made. In the first group, or those caused by cylindrical or conical weapons, when the weapon is very fine it may leave no track at all; if a little larger, we may infer from a linear bloody track that the weapon was needle-like in shape. The length of the instrument or the depth to which it penetrated may be found, as a rule, only by dissection. If the weapon were larger and conical, we have seen that the wounds would be linear with two angles, the length of the wound being parallel to the direction of the fibres in the skin.
Here we may judge of the form of the weapon from the following circumstances: From a comparison of the depth with the size of the opening, we know that it was a punctured wound. The edges and angles are not smooth and even enough for a stab-wound with a knife, for the edges are torn and not cut, and a stab-wound would be the only form of wound with which we would be likely to confuse it. Furthermore, the direction of the long axis of the wound parallel to that of the skin fibres in the region in which it occurs and the very slight retraction of the edges distinguish it from a stab-wound. By these signs we can almost always distinguish such wounds from stab-wounds, and thus tell the form of the weapon used. As to the size of weapon used, these wounds if of any size are generally smaller than the weapon, for the skin is put on the stretch by the weapon and yields to a certain extent. The actual wound, therefore, is smaller in circumference than the weapon. The size of the wound is smaller than that part of the weapon occupying the wound when the weapon was arrested; it may be very much smaller than the weapon at its largest point. Small wounds of this kind are generally larger than the instrument producing them.
The second group of punctured wounds, or stab-wounds, are by far the most common and, therefore, the most important variety of punctured wounds. If the stab-wound is perpendicular to the surface the form of the wound may represent pretty closely that of the weapon at the point where the latter was arrested, whether it has a single or double cutting edge. But even here there are exceptions. Frequently a weapon with a broad back and only one cutting edge may produce a wound resembling that of an instrument with two cutting edges, the second angle tearing as in the former class. Here on close examination we can sometimes distinguish the difference between the two angles, and judge correctly of the shape of the weapon. In fact, wounds made by common pocket-knives are regularly slit-like and not wedge-shaped, as the wound is caused only by the cutting edge of the knife. Again, if the single cutting edge is blunt, in rare cases the wound is produced in the same manner as those of the first group, or conical and cylindrical instruments. We would be led to suppose that the wound was produced by such an instrument, as both angles are torn, unless the direction of the wound might not follow that of the fibres of the skin, in which case we would be left in doubt. Stab-wounds are sometimes angular from the knife being withdrawn in a slightly different direction from that in which it was introduced or from an unequal retraction of the skin (see Fig. 9). If the stab-wound is obliquely directed, we can still judge of the general shape of the weapon, with exception of the cases above mentioned. The dimensions and size of the weapon are here much harder to determine. The dimensions of a stab-wound in the skin may be the same as those of the weapon, or of that part of the weapon which is arrested in the wound, but often they are not so. To measure the size of a wound exactly so as to get at the exact size of the instrument, we should place the region of the wound in the same position, etc., that it was when the wound was inflicted, and this we cannot often do. As the skin was tense or relaxed at the time the wound was inflicted, so the wound in the skin appears smaller or larger, just as with a sheet of rubber under similar conditions. If the instrument is very blunt, the wound in the skin may be smaller than the weapon whether the skin near the wound is tense or not. Thus Hofmann saw the wound from a blunt bayonet one centimetre shorter than the weapon.
The wound of the skin may be shorter and broader than the weapon used on account of retraction of the edges of the wound, and this is especially marked when the wound lies transversely to the direction of the skin fibres. On the other hand, the length of the external wound is more often greater than that of the weapon, because the wound is elongated by making pressure toward the cutting edge on withdrawal of the weapon, and an oblique wound measures longer than the weapon. If the blow is from above downward and the cutting edge of the weapon is uppermost, the length of the wound is not so likely to be increased much beyond the measurement of the weapon as when the cutting edge is directed downward. There is but one condition in which a stab-wound is at all likely to correspond in dimensions with that of the weapon, and that is when the wound is perpendicular to the surface. Even here the wound may be lengthened on withdrawal of the weapon, and we have to allow for retraction of the edges and try to put the parts in the same condition of tension or laxity as at the time of wounding. Even in the most favorable case, therefore, we cannot with certainty tell the exact size of the weapon. If a stab-wound be directed obliquely to the surface, then the length of the wound is greater than that of the weapon, unless this increase be exactly counterbalanced by the lateral retraction of the wound. The size of the weapon in such oblique wounds is further obscured by the changes of size due to withdrawal of the weapon, retraction of the edges, and the condition of the tension of the skin at the time the wound was inflicted.