Editing Papua New Guinea (section)

=== Law ===
{{main|Law of Papua New Guinea}}
[[File:Port Moresby parliament building front, by Steve Shattuck.jpg|thumb|upright|The Parliament building of Papua New Guinea in [[Port Moresby]]]]
The unicameral Parliament enacts legislation like in other Commonwealth realms that use the Westminster system of government. The cabinet collectively agrees on government policy, and then the relevant minister introduces bills to Parliament, depending on which government department is responsible for implementing a particular law. Backbench members of parliament can also introduce bills. Parliament debates bills (section 110.1 of the Constitution), which become enacted laws when the Speaker certifies that Parliament has passed them. There is no Royal assent.

All ordinary statutes enacted by Parliament must be consistent with the Constitution. The courts have jurisdiction to rule on the constitutionality of statutes, both in disputes before them and on a reference where there is no dispute but only an abstract question of law. Unusually among developing countries, the judicial branch of government in Papua New Guinea has remained remarkably independent, and successive executive governments have continued to respect its authority.

The "underlying law" (Papua New Guinea's [[common law]]) consists of principles and rules of common law and equity in English<ref>Papua New Guinea Constitution Schedule 2.2.2</ref>{{Primary source inline|date=April 2025}} common law as it stood on 16 September 1975 (the date of independence), and thereafter the decisions of PNG's own courts. The Constitution directs the courts and, latterly, the ''Underlying Law Act'' to take note of the "custom" of traditional communities. They are to determine which customs are common to the whole country and may also be declared to be part of the underlying law. In practice, this has proved difficult and has been largely neglected. Statutes are largely adapted from overseas jurisdictions, primarily Australia and England. Advocacy in the courts follows the adversarial pattern of other common-law countries. This national court system, used in towns and cities, is supported by a village court system in the more remote areas. The law underpinning the village courts is 'customary law'.