Legal positivism is a view that law is man-made and has not, in itself, any inherent connection to morality or ethics. According to this view, laws are neither "good" nor "bad" in the very nature of it; it is just a rule created by an appropriate authority. It means that for legal positivists, the validity of the enactment by a legitimate authority or otherwise, is immaterial but whether it measures up to the moral or ethical standards. This way, we can learn to consider the law as an objective system, something which need to be separated from subjective values.

Legal positivism was a reaction against natural law theories, the former believing that "the task of the lawyer is to determine what actually exists, rather than what should exist." Natural law theorists hold that an unjust law is not, in fact, a law; legal positivists deny this. They believe that law can and should be studied on its own terms, unrelated to its being "right" or "wrong," morally.

Two of the most prominent figures in the legal positivist tradition are H.L.A. Hart and Hans Kelsen. For Hart, primary and secondary rules explained how legal systems worked as a coherent system of obligation-creating and obligation-changing rules versus rules that described what was being done with those obligations. He also observed that the social acceptance gave the laws their authority.

Where Kelsen differed was with the "Pure Theory of Law." Here, he focused entirely on the internal structure of law and aimed to isolate law from external influences such as morality or social environment. In other words, natural law theorists believe that laws ought to embody ethical values; Kelsen responded that a law is valid if it has been enacted through appropriate authority and process irrespective of its content.