How to Use

Laws 001

Not quite Laws 101, this is a quick guide into the principles of how to do legal research in New Zealand.

What is law?

Law in New Zealand is mostly made up of legislation (Acts of Parliament) and case law (decisions of Judges in Courts).

Case law applies and interprets legislation, and it can be helpful for understanding how legislation works. Sometimes the Courts can make their own law too.

You can view and browse all of New Zealand’s legislation at the Parliamentary Counsel Office website,

You can use OpenLaw NZ to find case law that might help you find the answer to a legal question. This is how.

New Zealand Court structure

First, understand the Courts structure. The Court system in New Zealand is structured in a hierarchy. From top to bottom:

  1. The Supreme Court
  2. The Court of Appeal
  3. High Court
  4. District Court (including Family Court and Youth Court)
  5. Tribunals (including the Disputes Tribunal and others)

Decisions of courts higher in rank are binding on those of lower rank. That is, given the same legal issue, a decision of the Supreme Court must be followed by all lower courts.

Therefore, if you have a legal question, decisions issued by higher courts will be the most useful for telling you what the law is and how it should be applied. If you can find a Supreme Court case on topic, that will be the most authoritative and useful, because anything the Supreme Court says, all other Courts must follow.

How to find an answer to a legal question

Step 1 – identify the relevant law

The easiest place to start is with the section (or sections) of an Act of Parliament that apply to your situation. For example, if you want to know about parenting orders, you need to find law about section 48 of the Care of Children Act 2004.

If you have a legislation title and section, or even just a legislation title, go to the next step.

If not, you can either see if you can find the relevant Act by reviewing relevant government websites (they will normally tell you what legislation is relevant) or searching on It might take you a few tries, but search through the legislation until you have at least one section that you think is relevant to your situation.

Step 2 – Confirm the section is relevant and understand how it is applied

Once you have a section of an Act, you can look at case law. Case law will help you understand what that section means and how it is applied.

You can use OpenLaw NZ to find case law that talks about sections in two different ways:

  • Use the Advanced Search. Choose “Legislation” from the drop down. Enter the title of the Act, and the section number.
  • Use the Chrome Extension (if you’re using the Chrome web browser). Install the extension, then navigate on to the section you’re interested in. Click the OpenLaw NZ button to view a list of cases that talk about it.

Alternatively, you can use OpenLaw NZ fulltext search to find cases with relevant facts or law. See below for some guidance on how you can use our search.

Step 3 – Find related cases

Once you have a case, it might be helpful to see if other cases talk about it. If lots of cases talk about it, that is generally a sign that it is an important case. Likewise, it is important to check that the case has not been overruled by a higher Court.

If the case you've found is not quite right for your situation, you could look at cases cited by the case for further guidance on the relevant legal principles. If the case refers to another case and indicates that the other case is more authoritative or important, you should check that other case.

You can navigate to and see other cases cited by a case (cases referred to by the present case), or other cases that cite a case (other cases that refer to the present case), using the information on the right side of the page.

Using the API

Terms of use

By using our API you agree to theAPI Terms of Use

What the API does

The OpenLaw NZ API facilitates programmatic access to our case law data. This means you can integrate case law data and insights into your own applications or services.

If you would like to use our API please get in touch with us and we'll provide you with an API key