A new era began in 1936 following the appointment of H. G. R. Mason as Attorney-General in the first Labour Government and the creation of an organisation in the Justice Department to initiate and study proposals for reform. For the first time, law reform was pursued systematically and on a full-time basis. Another innovation was the establishment in 1937 of the Law Revision Committee to bring outside interests regularly into the work of reforming the law. This did much to improve the quality of legislation of a more legal character. The volume and range of legislation since 1936 has been great, but the most fundamental development was probably the adoption of the Statute of Westminster in 1947. Hitherto legislation inconsistent with an Act of the British Parliament extending to New Zealand was invalid, and British legislation could theoretically over-ride any New Zealand Act. Since 1947 the New Zealand Parliament has been fully sovereign, and there are no legal restrictions on the laws it can make.

Much legislation is avowedly social or economic and reflects the policy of the party in power. Relationships between the law and the social system are equally close, however, at what may be called the subpolitical level. Social and legal reform in New Zealand over the past 90 years has been an unbroken process, now speeding up, now faltering, but illustrating an underlying continuity in our history, and its rhythm has not followed closely the political complexion of Governments.

One persistent theme is a preoccupation with the welfare of the family, particularly wives and children. In this sphere New Zealand has never been content simply to follow others. This is testified by legislation relating to adoption, family protection, joint family homes, the capitalisation of family benefits, and many other matters. Even the extensions of the grounds of divorce have had as a principal object the helping of families by giving legal status to stable de facto unions. Much of the licensing legislation affords another instance, since a dominant motive was to save the family from the abuses of liquor.

A related tradition is the intervention of the State to assist the small man whose ambitions are independence, security, and a modest living. While the law has shown a deep distrust of that figure, supposedly typical of our society, the man alone, it has tried to give reality to the image of New Zealand as the paradise of the common family man. Likewise, numerous statutes license and regulate those on whose honesty or skill others must rely. Although this is not unique to New Zealand, it is characteristic.