Before there was a law under the American Constitution, there was an argument about the law. It was an argument, that is, about the ends of the law, and the framework of a lawful government. This was, of course, the argument over the Constitution, and it seems remarkably to have escaped recognition these days that an argument of this kind is itself a dramatic illustration of “natural law.” After all, the very appeal to first principles as the ground of a constitution is itself a move into natural law. If a constitution is to make sense, it must presuppose that there are certain principles of lawfulness that existed, as truths commanding our respect, even before a constitution was framed and enacted.
As John Locke pointed out, the legislature would be the source of the “positive law,” the law that was enacted or posited. But what, he asked, would be the source of the legislature? From what would that spring? The origin was to be found, as Locke said, in understandings that were “antecedent to all positive laws.” The ultimate authority to establish a constitution and a legislature depends “wholly on the people.” Before there is a legislature or a constitution defining a legislature, there is the right of a people to govern itself by forming a constitution and bringing forth a government restrained by law.
James Wilson made this same point in the first case that elicited a set of opinions from the Supreme Court (Chisholm