Born in Bridge of Weir, Renfrewshire, Scotland, and educated at Queen's University, Canada, and at Nuffield College, Oxford, he completed his dissertation—which culminated in a book, The Authority of the State—under professors Charles Taylor and later Joseph Raz.
In 2006, Green was elected to the Professorship of Philosophy of Law at Oxford University, which includes a Fellowship at Balliol College. The Professorship, a new statutory chair, was created upon the retirement of Joseph Raz from his personal Chair, also at Balliol. It is one of just two statutory professorships in jurisprudence at Oxford, the other being held by John Gardner. In 2010, the distinguished lawyer, Philip Gordon, endowed the Balliol fellowship, and Green became the first Pauline and Max Gordon Fellow at Balliol. At the same time, Green took up a part-time appointment as Professor and Distinguished University Fellow in the Philosophy of Law at Queen's University. Green is also an Adjunct Professor at McMaster University.
Prior to this, Green taught for most of his career at Osgoode Hall Law School of York University, in Toronto. He has also taught at Lincoln College, Oxford, at Boalt Hall Law School at the University of California, Berkeley; at the University of Chicago Law School, and was for several years a Regular Visiting Professor at the University of Texas at Austin law school. He has been a visiting fellow at Columbia University's Center for Law and Philosophy, and a Hauser Global Faculty member at New York University School of Law.
Green writes on political philosophy, legal obligation and authority, legal reasoning, as well as on moral and legal issues surrounding sexuality. His work defends surprising combinations of ideas. He is a defender of legal positivism who argues that there are many necessary connections between law and morality. He denies that there is a general duty to obey the law, but thinks reasonably just legal systems are morally valuable and are to be defended where they exist and established where they do not. He is a liberal in sexual ethics who maintains that sexual objectification is sometimes a good thing.
- Leslie Green's Oxford faculty page
- Green on authority and obligation
- Green on legal positivism