Science and the Criminal

by C. Ainsworth Mitchell

In the words of the prosecuting counsel for the prisoners—“they say that if a man or any other creature be strangled or hanged and the body cold and the blood settled in the veins (as he must be if your evidence be true, meaning the evidence of the said Miles Praunce). Run twenty swords through such a body not one drop of blood will come out; but, on the contrary, his body when found was full of blood. So that they do aver that that wound that he received by that sword must be the cause of death.”

William Batson, who was one of the principal witnesses for the prosecution, stated: “They showed me in a ditch where they said he lay some blood. I cannot say it was his blood; and going a little further I saw some more whitish blood, and this is all I can swear.”

The Lord Chief Justice (Scroggs) then asked if the weather had been frosty, to which the witness replied: “My lord, I cannot tell whether it was, but I will assure you the blood looked to me more like blood that was laid there than anything else.”

After a lengthy trial, in which the main evidence of the former trial, which was quite unconvincing, was repeated, the prisoners were found guilty of traducing the justice of the nation and two of them were sentenced to stand for an hour in the pillory and pay a fine of £100 each, while the third escaped with the fine only.

Where stains have been found upon the clothes or on a weapon in possession of an accused person and have been proved to consist of blood, the defence has frequently been set up that they were caused by the blood from a sheep that had been killed or from handling game.

Ten years ago, prior to the discovery of the serum test, it would not have been possible, except in the cases where the blood corpuscles could be examined, to prove or disprove this except by corroborative evidence. There was no chemical means of determining whether an old blood stain had been caused by the blood of a man or that of an animal.

Taylor, writing in 1844 upon this point, observes: “Some French medical jurists state that by mixing fresh blood with a certain portion of sulphuric acid and agitating the mixture with a glass rod a peculiar odour is evolved which differs in the blood of man and animals, and also in the blood of the two sexes. This odour, it is said, resembles that of the cutaneous exhalation of the animal, the blood of which is the subject of experiment. They have hereby pretended to determine whether any given specimen of blood had belonged to a man, a woman, a horse, sheep, or fish. Others pretend that they have been able to identify the blood of frogs and fleas!”

As Taylor pertinently observes of this: “There is probably not one individual among a thousand whose sense of smelling would be so acute as to allow him to state with undeniable certainty, from what kind of animal the unknown blood had really been taken. Any evidence short of this would not be received in an English court of law.”

On the first occasion upon which scientific evidence as to the difference between the blood of man and of animals was given in a criminal trial the remarks made by the judge (Lord Chief Justice Cockburn) to the jury showed that he was sceptical as to the powers claimed by the chemical witness of distinguishing between different kinds of blood.

In this case, which was tried at the Taunton Assizes, in 1857, a man had been found with his throat cut, and collateral evidence pointed to a man named Nation being the murderer. When he was arrested he was found to have a knife upon him on which were stains that appeared to be blood, but the prisoner accounted for these by saying that he had recently been cutting raw beef with the knife.