In legal history, an animal trial was the criminal trial of a non-human animal. Such trials are recorded as having taken place in Europe from the thirteenth century until the eighteenth. In modern times, it is considered in most criminal justice systems that non-human creatures lack moral agency and so cannot be held culpable for an act.
Animals, including insects, faced the possibility of criminal charges for several centuries across many parts of Europe. The earliest extant record of an animal trial is the execution of a pig in 1266 at Fontenay-aux-Roses. Such trials remained part of several legal systems until the 18th century. Animal defendants appeared before both church and secular courts, and the offences alleged against them ranged from murder to criminal damage. Human witnesses were often heard and in Ecclesiastical courts they were routinely provided with lawyers (this was not the case in secular courts, but for most of the period concerned, neither were human defendants). If convicted, it was usual for an animal to be executed, or exiled. However, in 1750, a female donkey was acquitted of charges of bestiality due to witnesses to the animal's virtue and good behaviour while her human co-accused were sentenced to death.
Translations of several of the most detailed records can be found in E.P. Evans' The Criminal Prosecution and Capital Punishment of Animals, published in 1906. Sadakat Kadri's The Trial: Four Thousand Years of Courtroom Drama (Random House, 2006) contains another detailed examination of the subject. Kadri shows that the trials were part of a broader phenomenon that saw corpses and inanimate objects also face prosecution; and argues that an echo of such rituals survives in modern attitudes towards the punishment of children and the mentally ill.