The 2020 edition of the Cambridge University Press Legal Studies Stage 6 Year 12 textbook defines the ‘adversary (or adversarial) system’ as:
The key aim of the adversary system is to ensure fairness between both the Defence and the Prosecution throughout the trial process (learn more about these parties at (c) People in Court).
Equality of Representation
Under the adversary system, both parties are afforded the right to seek a lawyer to represent them, and each side is provided with an equal opportunity to present their arguments and evidence in court – no verdict can be reached until both the Defence and Prosecution have rested their cases and the final arguments have been presented. A typical criminal trial will follow the process illustrated below:
As you can see, the trial process under the adversary system gives both the Prosecution and the Defence a fair chance to make their assertions, as well as opportunities to rebut each other in the final arguments.
As outlined by Her Honour Judge Culver in her discussion on the rule of law “at every point along the way you have the right to know what is happening, what the evidence is against you and the right to be heard and the right to give your perspective of the events. And this continues all along. If you are found guilty, you have the right to appeal”
Some criticisms have been made against the ‘fairness’ of the adversary system, particularly regarding the possible imbalances of resources, skills or knowledge that may occur between the Prosecution and Defence. For example, could an accused who can’t afford an experienced or qualified lawyer still have an ‘equal’ chance against an adversary who does? The model litigant rules aim to help this imbalance when the other party is a government department but for other parties, this will be covered in (e) Access to Justice.
Impartiality of the Judiciary
Under the adversary system, it is important that the judges and juries of criminal cases exhibit impartiality through procedural justice in order to uphold the rule of law. As Steven Rares wrote in his article What is a Quality Judiciary?, “Impartiality requires not only that the judge have no actual or perceived personal interest of any kind in the result of a case, but also that he or she has the courage to arrive at and enforce the result according to law”. The judiciary must also consciously ignore the influences of the media or their own external experiences, focusing only on the contents of the case. Read more on this at (f) Burden and Standard of Proof and (i) The Role of Juries.