The English notion of the proper prosecutorial role as that of the non-partisan 'minister of justice' was expressed in Australia by colonial legal practitioners but in practice the application of this role was to often prove a matter of rhetoric rather than of reality. Prosecutors in practice often acted as zealous and partisan advocates. This article considers the development of the prosecutorial role in Australia from 1824 to the early 20th century and, in particular, the extent to which the minister of justice model was applied in Australia. Factors that influenced the perception and performance of the prosecutorial role during this period are examined. It is suggested that colonial prosecutors in practice were motivated by subjective factors such as the class or race of the accused and the nature of the crime that they were charged with. Prosecutorial zeal appears explicable, not by the tension of acting in an adversarial system, but in confronting defendants who were regarded as 'criminals of the deepest dye' who posed a real 'threat' to colonial society. Though the minister of justice role was applied in Australia on occasion, it was often reserved for 'respectable' defendants and to be the apparent product of class bias rather than genuine prosecutorial restraint. Nevertheless, despite the inconsistent development in Australia of the minister of justice role, as the 19th century progressed, it was increasingly applied as a matter of both rhetoric and reality, reflecting the increasing stability and confidence of the Australian colonies.