The role of a judge is to make or facilitate decisions in accordance with New Zealand’s laws. In order to perform this role, a judge must apply the laws which are passed by Parliament. Parliament, which is democratically elected, passes laws which reflect the intention or interests of New Zealanders. In this way, society’s standards and views are formally expressed by the enforcement of laws.

The laws passed by Parliament are known as statutes, and are available to download from the New Zealand Legislation website(external link).

When interpreting the laws passed by Parliament, judges will also consider cases decided by other judges and courts. These are known as precedents. In particular, District Court Judges are bound to consider relevant decisions of the High Court, Court of Appeal, and Supreme Court. This ensures that the law remains consistent, and that any gaps or ambiguities in the laws passed by Parliament are resolved. Before making a decision about how to interpret the law, a judge will hear arguments from both sides (normally via their lawyers).

This process of considering statutes passed by Parliament together with precedents is known as the common law system. The common law system is used in many current or former Commonwealth democracies, such as the United Kingdom, Canada, Australia, and the United States of America.

An example of common law decision-making is the assessment of an appropriate sentence for someone who has been found guilty of a criminal offence. The statute passed by Parliament, such as the Sentencing Act 2002, may set a maximum penalty for a particular offence. The District Court Judge will then consider the appropriate penalty with regard to the factors set out in the statute, and the penalties imposed in similar decisions by other courts.