From the Public Domain Review:
All over Europe, throughout the middle-ages and right on into the 19th century, animals were, as it turns out, tried for human crimes. Dogs, pigs, cows, rats and even flies and caterpillars were arraigned in court on charges ranging from murder to obscenity. The trials were conducted with full ceremony: evidence was heard on both sides, witnesses were called, and in many cases the accused animal was granted a form of legal aid — a lawyer being appointed at the tax-payer’s expense to conduct the animal’s defence.
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The Pied Piper, who charmed the rats from Hamelin is a part of legend; but who has heard of Bartholomew Chassenée, a French jurist of the sixteenth century, who made his reputation at the bar as the defence counsel for some rats? The rats had been put on trial in the ecclesiastical court on the charge of having “feloniously eaten up and wantonly destroyed” the local barley. When the culprits did not in fact turn up in court on the appointed day, Chassenée made use of all his legal cunning to excuse them. They had, he urged in the first place, probably not received the summons since they moved from village to village; but even if they had received it they were probably too frightened to obey, since as everyone knew they were in danger of being set on by their mortal enemies the cats. On this point Chassenée addressed the court at some length, in order to show that if a person be cited to appear at a place to which he cannot come in safety, he may legally refuse. The judge, recognising the justice of this claim, but being unable to persuade the villagers to keep their cats indoors, was obliged to let the matter drop.