Magistrates' Courts are designed to provide more economical and expeditious adjudications than may be possible in the Crown Courts. It is the summary nature of Magistrates' Courts' determinations that justifies the defendant's statutory right to a rehearing in a Crown Court if he is dissatisfied with the result of his first trial. However the powers of a Crown Court on disposing of an appeal can deter defendants from lodging what they consider to be meritorious appeals. This article assesses the nature and legitimacy of those powers, which work in terrorem of appeals.