Born in Mandate Palestine in 1939, Joseph Raz graduated in 1963 from the Hebrew University, Jerusalem, Israel with a Magister Juris (Master of Jurisprudence), summa cum laude. Later, with funds provided by the Hebrew University, Raz pursued a Doctor of Philosophy (DPhil) at Oxford University under the supervision of H. L. A. Hart. This was by no means coincidental; Raz had met Hart earlier at a conference in Israel. Hart says that at this meeting, Raz pointed out a flaw in his reasoning that had previously eluded him. Hart encouraged him to go to Oxford for further study.

Raz studied at Balliol College, Oxford and was awarded the DPhil in 1967. He then returned to Israel to teach at the Hebrew University as a Lecturer in the Faculty of Law and Department of Philosophy. In 1971, he was tenured and promoted to Senior Lecturer. In 1972, he returned to Balliol as a Fellow and Tutor in Law, becoming a Professor of Philosophy of Law, Oxford University, from 1985 to 2006, and then a Research Professor from 2006 to 2009. Since 2002 he has also been a Professor in the Law School at Columbia University, New York. He has held visiting appointments at several universities, and has also served on a number of editorial boards for the publication of journals and books.

Raz is acknowledged by his contemporaries as being one of the most important living legal philosophers. He has authored and edited nine books to date, namely The Concept of a Legal System (1970), Practical Reason and Norms (1975), The Authority of Law (1979), The Morality of Freedom (1986), Authority (1990), Ethics in the Public Domain (1994), Engaging Reason (1999), Value, Respect and Attachment (2001), and The Practice of Value (2003).

His first book, The Concept of a Legal System, was based on his doctoral thesis. A later book, The Morality of Freedom won two prizes: the 1987 W.J.M. Mackenzie Book Prize from the Political Studies Association of the United Kingdom, awarded to the best book in political science each calendar year; and the 1988 Elaine and David Spitz Book Prize from the Conference for the Study of Political Thought, New York, awarded annually for the best book in liberal and/or democratic theory that had been published two years earlier.

The key ideas engaged in Raz's books are norms, authority, and the theory of legal positivism. His theory of norms refers roughly to rules that serve as a guide for human behaviour. It also includes the system(s) that those norms exist in, such as a legal system. The second aspect refers to questions on the authority that law has over people under a particular legal system, and the authority that society in general should acknowledge as due to the law. Such questions are important, for the law is in every corner of society, affecting the daily lives of individuals whether they like it or not. As Raz uses the term, 'legal positivism' refers to the view that there is no necessary conceptual relationship between law and morality; a law does not cease to be a law by being unjust or immoral. The term is sometimes used to describe the view that laws either cannot or even should not be grounded in morality; Raz does not defend that view.

His work has been cited by the Supreme Court of Canada in such cases as Imperial Tobacco v. British Columbia, R. v. Demers, and Sauvé v. Canada (Chief Electoral Officer).

In 1987 he was elected a Fellow of the British Academy. He has been awarded Honorary Doctorates by the Catholic University of Brussels, 1993, and by King's College London, 2009. In 2005 he received the International Prize for Legal Research 'Hector Fix-Zamudio' from the National Autonomous University of Mexico, and in 2009 a Vice-Presidency Award from the Law Society of University College Dublin.