Ratio, obiter and material facts 

The ratio decidendi is the legal reason for the decision. It is not every sentence in the judgment, and it is not merely the final order. It is the rule or principle that was necessary to decide the dispute on the material facts.

Obiter dicta are judicial observations that are not necessary to the result. Obiter can still be persuasive, especially when it comes from a higher court or from a carefully reasoned passage. The point is not to ignore obiter. The point is to identify its legal weight honestly.

Start with the dispute actually decided

A good case note starts with the litigation problem. Ask:

1. What facts did the court treat as legally significant?
2. What legal issue had to be resolved?
3. What rule or principle did the court apply?
4. What order followed from that reasoning?

The material facts are the facts that help explain why the rule operated as it did. In a negligence case, the material facts may include the relationship between the parties, the risk, the defendant's conduct and the kind of harm. In a statutory case, they may include the decision-maker, the power exercised, the words of the statute and the procedural step alleged to be invalid.

Worked example: extracting a ratio

Suppose a court decides that a decision made under a statute was valid even though a procedural step was not followed exactly. The ratio is unlikely to be "procedural steps do not matter". A more careful statement might be: where a statutory requirement regulates the exercise of power, invalidity depends on whether the legislature intended non-compliance to invalidate the act, assessed through text, context and purpose.

That statement is narrower, but much more useful. It identifies the legal test and leaves room for a different result if the statute, purpose or consequence is different.

Why material facts matter

Material facts are the bridge between authority and analogy. A later student answer often has to say: "this problem is like the earlier case because..." or "this problem is different because...". The because matters. It must point to facts that affected the rule, not decorative background.

A case can be distinguished when a material difference makes the earlier rule unsuitable or changes how it applies. A case is not distinguished simply because the parties, dates or setting differ.

Plurality, concurrence and dissent

Australian appellate judgments often contain several sets of reasons. A majority may agree on the result but not every step of reasoning. Read the orders, then identify which judges agree with which reasons. A joint judgment is usually easier to handle, but a fragmented court requires more care.

A dissent is not binding as the ratio of the case, but it may become influential later. It can also help expose the competing legal arguments that the majority rejected.

High Court dicta

High Court decisions can contain observations that are not strictly necessary to decide the appeal but are still powerful. In Farah Constructions Pty Ltd v Say-Dee Pty Ltd [2007] HCA 22 at [134], the Court referred to "seriously considered dicta".¹ For students, the lesson is simple: do not dismiss a High Court passage merely by calling it obiter. Explain whether it was central, careful, repeated, and connected to the issue you are analysing.

Whether that rule has one requirement or two is unsettled. In Harvard Nominees Pty Ltd v Tiller (2020) 282 FCR 530² the Full Court of the Federal Court — Lee, Anastassiou and Stewart JJ — set out the two readings Campbell JA had identified in Zotti v Australian Associated Motor Insurers Ltd [2009] NSWCA 323 and adopted the narrower: "The High Court has not definitively settled this issue, but it is our view that this approach is correct. That is, that there are two requirements, namely that the dicta conform with long-established authority and that they are the dicta of a majority of the High Court." Note what that is — an intermediate appellate court's view, on a question it says the High Court has not settled. Cite it as that, not as the rule.

Self-check

Before relying on a case, write one sentence for each of these:

• the material facts;
• the legal issue;
• the ratio;
• any important obiter;
• the court and its place in the hierarchy;
• why the case is binding, persuasive or only illustrative for your problem.

This discipline turns case reading into legal reasoning. It also stops citation from becoming a decoration added after the answer has already been guessed.