Criminal appeal

A criminal appeal was a procedure in English law to bring about the prosecution of an individual accused of some crime. A private individual (the "appellor") would accuse another (the "appellee") of a crime, without the need for proceedings to be brought by the crown. It possibly descended from the system of weregild.
Appeals were among the legal proceedings for which trial by combat was available.
An appeal could be used to accuse a subject of high treason. It could also be used by someone when either they or a close relation had been the victim of a crime, such as murder, rape or arson.
An acquittal following an appeal prevented any further prosecution for the same offence (the doctrine of double jeopardy), just as if the proceedings had been brought by the crown (by indictment). The person bringing the appeal would be punished.
Unlike crown prosecutions, if a person was convicted, the crown did not have the option of a pardon.
Appeals were abolished in England following the 1817 case of Ashford v Thornton where an appeal was withdrawn following the defendant requesting a trial by battle.