Part One presents an overview of problems with the current law regarding the meaning of "relating to trial on indictment," the lack of clarity and simplicity, different avenues for challenging decisions of the Crown Court exercising its appellate or committal for sentence jurisdictions, and different avenues for appealing decisions of magistrates' courts. An overview of the main provisional proposals of the Law Commission addresses the role of the High Court; appeal by case stated and judicial review; challenging convictions and sentences; challenging acquittals; challenging determinations, judgments, orders and rulings other than convictions, and sentences and acquittals; and magistrates' courts and the court martial. Part Two of this report explains the various avenues under the current law for challenging determinations, orders, and rulings made by magistrates' courts and the Crown Court in Criminal proceedings. Part Three considers the relevance of the European Convention on Human Rights. Part Four explains the Law Commission's provisional proposals for the framework under which the High Court's jurisdiction in relation to criminal proceedings in the Crown Court should be transferred to the Court of Appeal. Part Five presents the Commission's provisional proposals regarding the circumstances in which resort to the proposed statutory appeal should be permitted. Part Six considers the implications of the proposals for proceedings in magistrates' courts. Part Seven examines the implications of the proposals for the Court Martial and related courts. Appended summary of some empirical evidence