Neither the adversarial (United Kingdom) nor the inquisitorial (Germany) systems are perfect, but each system includes many elements borrowed from the other. The solution may be a hybrid form of both, with regard to providing the fairest possible trial based on checks and balances. It is noted that a system’s performance should not be measured by the number of yearly convictions, but by the number of miscarriages of justice. The risk of such miscarriages seems high in England and Wales, due to the typical weaknesses of the adversarial system. Due to critical evaluation and research, the public awareness of the risks of miscarriages of justice is high in England and Wales, whereas the German system seems to trust excessively in its own integrity. The German criminal justice system is based on the inquisitorial tradition of all continental or civil law systems. This is contrary to the procedure in Anglo-Saxon common-law countries (United Kingdom) which are characterized by adversarial principles. The function of the prosecution, its influence on investigations, and its role in pretrial and trial proceedings differ substantially between the two systems. In this chapter it is argued that miscarriages of justice are sometimes closely connected with prosecutorial performance. The differences in the respective roles of prosecutors in Germany and in the United Kingdom, from initial investigations to trial proceedings are delineated, as examples of the “inquisitorial” and “adversarial” systems of justice. Both systems’ vulnerabilities in generating miscarriages of justice are discussed. Tables, notes and references