This module is a resource for lecturers

Adversarial versus inquisitorial legal systems

The role of public prosecutors may differ depending on the legal tradition adopted in a particular country. Two types of legal traditions dominate the nature of investigation and adjudication around the world: adversarial and inquisitorial legal systems. Common law countries use an adversarial system to determine facts in the adjudication process. The prosecution and defence compete against each other, and the judge serves as a referee to ensure fairness to the accused, and that the legal rules criminal procedure followed. The adversarial system assumes that the best way to get to the truth of a matter is through a competitive process to determine the facts and application of the law accurately.

The inquisitorial system is associated with civil law legal systems, and it has existed for many centuries. It is characterized by extensive pre-trial investigation and interrogations with the objective to avoid bringing an innocent person to trial. The inquisitorial process can be described as an official inquiry to ascertain the truth, whereas the adversarial system uses a competitive process between prosecution and defence to determine the facts. The inquisitorial process grants more power to the judge who oversees the process, whereas the judge in the adversarial system serves more as an arbiter between claims of the prosecution and defence (Dammer and Albanese, 2014; Reichel, 2017).

Both these systems have variations around the world, as different countries have modified their criminal procedure in various ways over the years in balancing the interests of the State in apprehending and adjudicating offenders with the interests of individual citizens who may be caught up in the legal process. As this Module will show, these different legal traditions impact the ways in which criminal cases are investigated and prosecuted.