Though there are different versions of natural law theory, all subscribe to the thesis that there are at least some laws that depend for their "authority" not on some pre-existing human convention, but on the logical relationship in which they stand to moral standards.
Otherwise put, some norms are authoritative in virtue of their moral content, even when there is no convention that makes moral merit a criterion of legal validity.
Conversely, one could, though this would be unusual, accept a natural law theory of law without holding a natural law theory of morality.
One could, for example, hold that the conceptual point of law is, in part, to reproduce the demands of morality, but also hold a form of ethical subjectivism (or relativism).
On this peculiar view, the conceptual point of law would be to enforce those standards that are morally valid in virtue of cultural consensus.
For this reason, natural law theory of law is logically independent of natural law theory of morality.According to natural law moral theory, the moral standards that govern human behavior are, in some sense, objectively derived from the nature of human beings and the nature of the world.While being logically independent of natural law legal theory, the two theories intersect.Geoffrey Sayre-Mc Cord (1988), for example, views moral objectivism as one species of moral realism, but not the only form; on Sayre-Mc Cord's view, moral subjectivism and moral intersubjectivism are also forms of moral realism.Strictly speaking, then, natural law moral theory is committed only to the objectivity of moral norms.Lastly, Ronald Dworkin’s theory is a response and critique of legal positivism.All of these theories subscribe to one or more basic tenets of natural law legal theory and are important to its development and influence.One can deny natural law theory of law but hold a natural law theory of morality.John Austin, the most influential of the early legal positivists, for example, denied the Overlap Thesis but held something that resembles a natural law ethical theory.Indeed, Austin explicitly endorsed the view that it is not necessarily true that the legal validity of a norm depends on whether its content conforms to morality. Here it is worth noting that utilitarians sometimes seem to suggest that they derive their utilitarianism from certain facts about human nature; as Bentham once wrote, "nature has placed mankind under the governance of two sovereign masters, pain and pleasure.But while Austin thus denied the Overlap Thesis, he accepted an objectivist moral theory; indeed, Austin inherited his utilitarianism almost wholesale from J. It is for them alone to point out what we ought to do, as well as to determine what we shall do.