It is impossible, however, to make a precise list of the conventions of the constitution, for they are constantly changing by a natural process of growth and decay; and while some of them are universally accepted, others are in a state of uncertainty. Hence one hears from time to time a member of the Opposition assert that some action of the government is unconstitutional, meaning that it is an unusual breach of a principle which in his opinion ought to be recognised as inviolable. It was said, for example, that the Parliament of 1900, having been elected on the issue of the South African war, was not justified in enacting measures of great importance on other subjects, but that a fresh mandate from the nation ought to be obtained by another general election. As claims of this kind are in dispute, those customs alone can safely be said to be a part of the constitution which are generally assumed to be outside the range of current political controversy. [Sidenote: The Relation of Law and Custom.] The relation between law and custom in the English government is characteristic. From the very fact that the law consists of those rules which are enforced by the courts, it follows that the law,--including, of course, both the statutes and the Common Law,--is perfectly distinct from the conventions of the constitution; is quite independent of them, and is rigidly enforced. The conventions do not abrogate or obliterate legal rights and privileges, but merely determine how they shall be exercised. The legal forms are scrupulously observed, and are as requisite for the validity of an act as if custom had not affected their use.[10:1] The power of the Crown, for example, to refuse its consent to bills passed by the two Houses of Parliament is obsolete, yet the right remains legally unimpaired. The royal assent is given to such bills with as much solemnity as if it were still discretionary, and without that formality a statute would have no validity whatever. Public law in countries where it is administered not by the ordinary courts, but solely by the executive, or with the aid of special tribunals composed of administrative officials, must of necessity contain a discretionary element, and that element is always affected by political conventions. Hence there is a likelihood that the line between law and convention will become blurred, but this is not so in England. There the law and the conventions of the constitution are each developing by processes peculiar to themselves, but the line between them remains permanently clear. The conventions are superimposed upon the law, and modify political relations without in the least affecting legal ones. In fact Freeman declared that the growth of the unwritten conventions of the constitution began after the supremacy of the law had been firmly established by the revolution of 1688, and that they could not have been evolved if that condition had not existed.[11:1] [Sidenote: The Sanction of Custom.]