- Precedent and res judicata:
- Tribunals are bound by case law handed down by the courts.
- No formal doctrine of precedent applies to decisions of tribunals, however, previous tribunal decisions may be persuasive.
- There is conflicting judicial and tribunal authority as to whether res judicata (cause of action estoppel) and issue estoppel apply to a decision of a tribunal.
The rules of precedent have a more limited application to rulings on the meaning of particular legislation. A ruling of a court on the meaning of a legislative provision does not bind a tribunal which is interpreting a different statute, even if the same word or phrase is used.23
Assessing the value of a non-binding precedent
Even if a ruling in a prior decision is not binding because:
- it is obiter dicta
- it interprets a different statute
- it is from a tribunal, a lower court in the same hierarchy, or a court in the hierarchy of another jurisdictionit may still be persuasive, provided that it does not conflict with another precedent that is binding. A number of factors affect a tribunal’s assessment of how persuasive a precedent is, including:
- the quality of the reasoning and analysis to be found in it
- the extent to which it takes account of relevant precedents and related principles of law
- the standing of the court or tribunal which handed down the decision
- whether other courts or tribunals have applied it
- where the precedent relates to the interpretation of a different statute—the similarity of that statute to the one being interpreted in terms of its subject matter, purpose and language.It is good practice to refer to any relevant precedent that is known to the tribunal, whether binding or not, and to discuss whether it should be followed.
Rules of precedent
Courts are arranged in hierarchies, to provide a structure for appeals and to reserve more complex or important cases for more senior judges. Each jurisdiction—New Zealand, the Commonwealth and each state and territory—has its own hierarchy of courts. The High Court of Australia stands at the apex of all the Australian hierarchies and the Supreme Court of New Zealand at the apex of the New Zealand court hierarchy. The rulings of a court are binding upon courts that are lower in the same hierarchy of courts.
Usually, tribunals are not part of the court hierarchy. A tribunal is, however, bound by the rulings of:
- a court to which the tribunal’s decision may be appealed on a question of law
- a court which is empowered to review decisions of the tribunal in accordance with the common law process of judicial review
- any court which stands above those courts in the judicial hierarchy.
- Tribunals are not bound by propositions of law laid down in the decisions of another tribunal which was not exercising judicial power. For consistency, however, tribunal members follow decisions of an appeal panel of the tribunal. A more complex position arises for tribunals which exercise judicial power (such as certain divisions of the amalgamated civil and administrative tribunals in the Australian states and territories). Regardless of whether they are formally binding, tribunal decisions may be ‘persuasive’. It is highly desirable that tribunals maintain, so far as possible, consistency of decision-making within a tribunal. This can be achieved by applying a prior tribunal decision where convinced of its value on the basis of a thorough consideration of the factors, The reasons for this approach have been summarised as follows:
The Tribunal should only refuse to follow a decision of the Appeal Panel or the Tribunal as constituted by the President or the Deputy Presidents if it concludes that the previous decision is clearly wrong. (Judicial Member M A Robinson, Rittau v Commissioner of Police, New South Wales Police Service [2000] NSWADT 186).Common law method draws a distinction between the ratio decidendi (reason for deciding) and obiter dicta (things said by the way). Only the former is capable of binding courts and tribunals lower in the hierarchy. The ratio decidendi is any proposition of law expressly or impliedly used to reach the final decision, or to decide any issue that is a step towards the final decision. Any other statements of legal principle are obiter dicta and are not binding. The Tribunal is not bound by precedent or the doctrine of stare decisis in the strict sense in relation to being formally bound by earlier decisions of the Tribunal. However, for a number of reasons, I consider the Tribunal should ordinarily follow decisions of the Appeal Panel and decisions of the Tribunal as constituted by the President or the Deputy Presidents.
The reasons why these decisions should be followed is because they are authoritative and they go some way to seeking to ensure consistency in the Tribunal’s decision- making ...