The legal system includes the legislative machinery as well as the Courts. Legislation is primarily the function of Parliament. The Government accepts a positive responsibility for the continuous revision of the general law. The initiation and preparation of proposals for law reform is a function of the Department of Justice. An important part is also played by the Law Revision Committee, established in 1937. The Attorney-General is chairman. The Committee includes representatives of the Parliamentary Opposition, the legal profession, the University law faculties, and the principal legal Departments of State. Its role is to bring into the work of reforming the law those groups which by interest or expert knowledge can make a special contribution. Its existence ensures that law reform measures introduced into Parliament have been considered from different viewpoints and command a measure of informed support.

Public Acts and regulations are drafted in the Law Drafting Office. The ordinances of the 1840s, issued when New Zealand was a Crown Colony, began a tradition of good drafting that has continued to the present. Allowing for the inescapable complexity of much modern legislation, New Zealand statutes are distinguished by a clarity, accuracy, and simplicity that have been equalled in few other countries.