[9] Sometimes, however, a decision as to whether something that happened at, or in connection with, a criminal trial involved a miscarriage of justice requires an understanding of the circumstances, and such an understanding might involve knowledge of why it happened. A criminal trial is conducted as adversarial litigation. A cardinal principle of such litigation is that, subject to carefully controlled qualifications, parties are bound by the conduct of their counsel, who exercise a wide discretion in deciding what issues to contest, what witnesses to call, what evidence to lead or to seek to have excluded, and what lines of argument to pursue. The law does not pursue that principle at all costs. It recognises the possibility that justice may demand exceptions. Nevertheless, the nature of adversarial litigation, with its principles concerning the role of counsel, sets the context in which these issues arise. Considerations of fairness often turn upon the choices made by counsel at a trial. In TKWJ v R, the appellant complained that evidence of his good character was not led. This, it was said, was unfair. In rejecting that argument, this Court said that the failure to call the evidence was the result of a decision by counsel, and that, viewed objectively, it was a rational decision. That, in the circumstances of the case, was conclusive. It is the fairness of the process that is in question; not the wisdom of counsel. As a general rule, counsel's decisions bind the client. If it were otherwise, the adversarial system could not function. The fairness of the process is to be judged in that light. The nature of the adversarial system, and the assumptions on which it operates, will lead to the conclusion, in most cases, that a complaint that counsel's conduct has resulted in an unfair trial will be considered by reference to an objective standard, and without an investigation of the subjective reasons for that conduct.
42 The Chief Justice considered why an objective evaluation of counsel's conduct is preferable but also acknowledged that in some case it may be significant to understand why counsel acted as he or she did in order to determine whether there has been a miscarriage of justice. His Honour stated: