IV.—THE IMPORTANCE OF SMALL CLUES.
Detection depends largely, of course, upon the knowledge, astuteness, ingenuity, and logical powers of police officers, although they find many independent and often unexpected aids, as we shall see. The best method of procedure is clearly laid down in police manuals: an immediate systematic investigation on the theatre of a crime, the minute examination of premises, the careful search for tracks and traces, for any article left behind, however insignificant, such as the merest fragment of clothing, a scrap of paper, a harmless tool, a hat, half a button; the slow, persistent inquiry into the antecedents of suspected persons, of their friends and associates, their movements and ways, unexplained change of domicile, proved possession of substantial funds after previous indigence—all these are detailed for the guidance of the detective. It will be seen in the following pages how small a thing has often sufficed to form a clue. A name chalked upon a door in tell-tale handwriting; half a word scratched upon a chisel, has led to the identification of its guilty owner, as in the case of Orrock. A button dropped after a burglary has been found to correspond with those on the coat of a man in custody for another offence, and with the very place from which it was torn. The cloth used to enclose human remains has been recognised as that used by tailors, and the same with the system of sewing, thus narrowing inquiry to a particular class of workmen; and the fact is well illustrated in the detection of Voirbo, to be hereafter told. The position of a body has shown that death could not have been accidental. A false tooth, fortunately incombustible, has sufficed for proof of identity when every other vestige has been annihilated by fire, as in the case of Dr. Webster of Boston.
In one clear case of murder, detection was aided by the simple discovery of a few half-burnt matches that the criminal had used in lighting candles in his victim’s room to keep up the illusion that he was still alive. A dog, belonging to a murdered man, had been seen to leave the house with him on the morning of the crime, and was yet found fourteen days later alive and well, with fresh food by him, in the locked-up apartment to which the occupier had never returned. The strongest evidence against Patch, the murderer of Mr. Blight at Rotherhithe, was that the fatal shot could not possibly have been fired from the road outside, and the first notion of this was suggested by the doctor called in, afterwards eminent as Sir Astley Cooper. In the Gervais case proof depended greatly upon the date when the roof of a cellar had been disturbed, and this was shown to have been necessarily some time before, for in the interval the cochineal insects had laid their eggs, and this only takes place at a particular season. We shall see in the Voirbo case, quoted above, how an ingenious police officer, when he found bloodstains on a floor, discovered where a body had been buried by emptying a can of water on the uneven stones and following the channels in which it ran.
Finger-prints and foot-marks have again and again been cleverly worked into undeniable evidence. The impression of the first is personal and peculiar to the individual; by the latter the police have been able to fix beyond question the direction in which criminals have moved, their character and class, and the neighbourhood that owns them. The labours of the scientist have within the last few years produced new methods of identification, which are invaluable in the pursuit and detection of criminals. The patient investigations of a medical expert, M. Bertillon, of Paris (one of the witnesses in the Dreyfus case), developing the scientific discovery of his father, have proved beyond all question that certain measurements of the human frame are not only constant and unchangeable, but peculiar to each subject; the width of the head, the length of the face, of the middle finger, of the lower limbs from knee to foot, and so forth, provide such a number of combinations that no two persons, speaking broadly, possess them all exactly alike. This has established the system of anthropometry, of “man measurement,” which has now been adopted on the same lines by every civilised nation in the world. The system, however, is on the face of it a complicated one, and at New Scotland Yard it has now been abandoned in favour of the finger-prints method. Mr. Francis Galton, to whose researches this mode of identification is due, has proved that finger prints, exhibited in certain unalterable combinations, suffice to fix individual identity, and his system of notation, as now practised in England, will soon provide a general register of all known criminals in the country.
The ineffaceable odour of musk and other strong scents has more than once brought home robbery and murder to their perpetrators. A most interesting case is recorded by General Harvey,[1] where, in the plunder of a native banker and pawnbroker in India, an entire pod of musk, just as it had been excised from the deer, was carried off with a number of valuables. Musk is a costly commodity, for it is rare, and obtained generally from far-off Thibet. The police, in following up the dacoits, invaded their tanda, or encampment, and were at once conscious of an unmistakable and overpowering smell of musk,
which was presently dug up with a number of rupees, coins of an uncommon currency.
In another instance a scent merchant’s agent, returning from Calcutta, brought back with him a flask of spikenard. He travelled up country by boat part of the way, then landed to complete the journey, and carried with him the spikenard. He fell among thieves, a small gang of professional poisoners, who disposed of him, killing him and his companions and throwing them into the river. Long afterwards the criminals, who had appropriated all their goods, were detected by the tell-tale smell of the spikenard in their house, and the flask, nearly emptied, was discovered beneath a stack of fuel in a small room.
Yet again, the smell of opium led to the detection of a robbery in the Punjaub, where a train of bullock carts laden with the drug was plundered by dacoits. After a short struggle the bullock drivers bolted, the thieves seized the opium and buried it. But, returning through a village, they were intercepted as suspicious characters, and it was found that their clothes smelt strongly of opium. Then their footsteps were traced back to where they had committed the robbery, and thence to a spot in the dry bed of a river, in which the opium was found buried.
In India, again, many cases of obscure homicide have been brought to light by such a trifling fact as the practice, common among native women, of wearing glass, or rather shell lac, bangles or bracelets. These choorees, as they are called, are heated, then wound round wrist or ankle in continuous circles and joined. They are very brittle, and will naturally be easily smashed in a violent struggle. Fruitless search was made for a woman who had disappeared from a village, until in a field adjoining the fragments of broken choorees were picked up. On digging below, the corpse of the missing woman, bearing marks of foul play, was discovered.
In another case a father identified certain broken choorees as belonging to his daughter; they had been found, with traces of blood and wisps of female hair, near a well, and were the means of bringing home the murder. Cheevers[2] tells us that a young woman was seen to throw a boy ten years of age into a dry well twenty feet deep. Information was given, and the child was extracted, a corpse. Pieces of choorees were picked up near the well similar to those worn by the woman, who was arrested and eventually convicted of murder. Here the ingenious defence was set up that the child’s mother, a woman of the same caste as the accused, and likely to wear the same kind of bangle, had gone to wail at the well-side and might have broken her glass ornaments in the excess of her grief. But sentence of death was passed.