"Law's Empire" is a book written by legal philosopher Ronald Dworkin in 1986. It presents a theory of law that emphasizes the importance of moral principles in legal interpretation. Dworkin argues that law is not just a set of rules but also includes ethical considerations that judges must take into account when making decisions. In this work, Dworkin introduces the concept of "law as integrity," suggesting that legal practices should reflect a coherent set of moral values. He critiques legal positivism, which separates law from morality, and advocates for a more integrated approach to understanding legal systems and their role in society.