This exertion of actual and effective power by the Imperial Parliament throughout the United Kingdom is a totally different thing from the supremacy or sovereignty exercised by Parliament throughout the whole British Empire.  As a matter of legal theory Parliament has the right to legislate for any part of the Crown’s dominions.  Parliament may lawfully impose an income tax upon the inhabitants of New South Wales; it may lawfully abolish the constitution of the Canadian Dominion, just as some years ago it did actually abolish the ancient constitution of Jamaica.  But though Parliament does in fact exert a certain, or rather a very uncertain, amount of power throughout the whole Empire, we all know that the Imperial Parliament neither exercises, nor claims to exercise, in a self-governing colony such as New Zealand,[7] that kind of effective authority which Parliament exercises in the United Kingdom.  The Cabinet of New Zealand is not appointed at Westminster; the action of a New Zealand Ministry as regards the affairs of New Zealand is not controlled by the English Government.  Not a pennyworth of taxation is imposed on the inhabitants of New Zealand, or of any colony whatever, by the Imperial Parliament.  Even the imposition of customs, though it has an important bearing on the interest of the Empire, is in a self-governing colony determined by the colonial, and not by the British, Parliament.  It is the Parliament of New Zealand, and not the Parliament of England, which governs New Zealand.  The Imperial Parliament, though for Imperial purposes it may retain an indefinite supremacy throughout the British Empire, has, as regards self-governing colonies, renounced, for all other than Imperial purposes, executive and legislative functions.  To labour this point may savour of pedantry.  But the distinction insisted upon, whilst often overlooked, is of extreme importance.  We risk being deceived by words.  The Imperial Parliament is supreme in the United Kingdom, it is also supreme in New Zealand.  But the supremacy of the Imperial Parliament is a misleading expression; it means one thing in the United Kingdom, and another thing in New Zealand or in Canada.  In the United Kingdom it means the exercise of real, actual, effective and absolute authority.  In New Zealand it means little more than the claim to regulate matters of a distinctly and exclusively Imperial character.  The distinction is vital.  The essential feature of the English constitution is the actual and direct government of the whole United Kingdom by the Parliament at Westminster.  No change could be more fundamental than a change which, in England, Scotland, or Ireland, reduced this actual authority to the ultimate or reserved sovereignty exercised, or rather claimed, by Parliament in Canada or in New Zealand.

The negative characteristic of the English constitution is the absence of federalism or of the federal spirit.

The spirit of institutions is as important as their form, and the spirit of English Parliamentary government has always been a spirit of unity.