Professor Walen holds a joint appointment in the School of Law, the Philosophy Department (New Brunswick), and the Program in Criminal Justice (New Brunswick). He earned a B.A. at the University of Maryland, College Park, in 1987, a Ph.D. in Philosophy at the University of Pittsburgh in 1993, and a J.D. from Harvard in 1998. After law school, he clerked for District Court Judge Nancy Gertner (1998-99), and worked as an associate for the D.C. office of what was then Mayer, Brown and Platt (1999-2000), before entering the academic track in 2000.
His academic work focuses on the philosophical foundations of moral rights, with applications in criminal law, constitutional law, national security law, bioethics, and more. He has written over 30 substantial articles, published in peer review journal or law reviews, as well as numerous shorter pieces and encyclopedia entries. His first book, The Right to Defend Against Threats: A Case Study in Rights Theory, is due to be published by Oxford University Press in 2019. He also serves as an associate editor at Law and Philosophy.