This paper criticizes Alexy's argument on the necessary connection between law and morality. First of all, the author discusses some aspects of the notion of the claim to correctness. Basically, it is highly doubtful that all legal authorities share the same idea of moral correctness. Secondly, the author argues that the claim to correctness is not a defining characteristic of the concepts of “legal norm” and “legal system”. Hence, the thesis of a necessary connection between law and morality based on such claim cannot be accepted.