Science and the Criminal

by C. Ainsworth Mitchell

Early in the morning the housemaid found the silver plate scattered about the room, and various articles of value tied up in bundles, as though burglars had broken into the house and had been interrupted in their work.

She called Courvoisier, and he appeared almost immediately, fully dressed, and going into the room of Lord William Russell found him with his throat cut.

On a door were marks which indicated that it had been broken in by the supposed burglars, but closer examination showed that the damage had been done from the inside. In addition to this, any burglars entering the house through this door must have passed over a wall, and this was found to be thickly coated with dust which had not been disturbed.

For a long time no trace of the missing valuables were discovered, but finally after a thorough search of the premises, some of the money was found hidden behind the skirting in the pantry of the accused, while later on the stolen plate was discovered in the keeping of a man with whom Courvoisier had formerly lived.

Mainly on the circumstantial evidence of these facts the prisoner was convicted; afterwards he made a full confession of the crime.

Clever deductive reasoning was also shown in the following case, in which the author of a shooting outrage that occurred in 1831 at Ayr was discovered in a singular manner. Someone had maliciously fired a gun into a church, and had hoped to escape detection. It was noticed, however, that some of the bullets, after having passed through the windows, had left a mark upon the wall opposite. By drawing a straight line between these marks and the holes in the windows, and extending the line outside the church, the other end was found in a window on the other side of the street. Subsequently other proof was obtained that the gun had been fired from this window.

Numerous cases might also be quoted where the trained observation of a doctor has called attention to some slight point which would otherwise have been overlooked, but which has furnished the clue to the detection of a crime.

In the year 1806 a man named Blight was shot with a pistol at Deptford by someone unknown, and died from the wound. Sir Astley Cooper, who was called in to attend to the victim, carefully noted the relationship of the body to other objects in the room, and from the position of the wound concluded that the shot had been fired by a left-handed person. This inference drew suspicion upon a gentleman named Patch who was the only left-handed person who had been seen with Mr. Blight. He was a close personal friend of the latter, and no one had dreamed of suspecting him of the crime. The results of further inquiries proved that this man had fired the shot, and after his conviction he confessed that he had been guilty of the murder.

The fact that a weapon is tightly held in the hand of a person who has been shot is strong presumptive evidence that it is a case of suicide, since it is improbable that the hand of a dead man could subsequently be made to grasp a pistol.

There is a remarkable case on record, however, in which the fact that a pistol was found clenched in the hand of a dead man was at first regarded as evidence of a murder. A son of the deceased, who had slept in the same room was accused of having killed him and of then placing the discharged pistol in his hand to give the suggestion of suicide. Experiments were made in which the hand holding the pistol was lifted into the position in which it must have been held if it had been a case of suicide, and in each instance the hand, when allowed to fall, did not retain the pistol. For the defence medical evidence was given that the spasmodic contraction of the muscles after death would account for the pistol being still clenched in the hand, while the inability of the hand to grasp it afterwards did not prove anything. Evidence as to the presence of a motive was given, but the scientific evidence was regarded as decisive and the prisoner was discharged.