John C. Dehn
Professor & Faculty Director, National Security & Civil Rights Program
Professor John C. Dehn is a scholar of constitutional law, international law, and the law of armed conflict whose research focuses on war and emergency powers. His published work examines how constitutional text, historical practice, and international legal norms govern the use of military force, the exercise of emergency powers, and the allocation of authority among the branches of government. Drawing on constitutional and international legal history, he reexamines longstanding debates about executive power, congressional authority, the domestic status of international law, and the constitutional obligations of government officials.
His scholarship has informed academic debates and legal practice, appearing in legal briefs and government legal opinions addressing war powers, military operations, and international humanitarian law. His teaching reflects the same commitments: he connects historical understanding to contemporary legal problems, helping students learn to approach legal questions with factual and doctrinal rigor.
At Loyola, Professor Dehn teaches constitutional law as well as courses and seminars on public international law and its relationship to U.S. domestic law. He emphasizes close analysis of constitutional text, historical practice, and judicial precedent, and is committed to preparing students to approach consequential legal questions as careful and ethical practitioners.
Prior to joining Loyola, Professor Dehn served for over 23 years as an Army officer and lawyer in roles ranging from airborne field artillery officer to chief prosecutor for a military installation, detainee abuse prosecution team chief, and faculty member at West Point.
You can read more about the National Security and Civil Rights Program that Professor Dehn leads, including recent programs, academic presentations, publications, and other public appearances on the National Security and Civil RIghts website.
Education
LLM – Columbia Law School
LLM – The Judge Advocate General’s Legal Center and School, U.S. Army
JD (with highest honors) – University of Oklahoma College of Law
BS – United States Military Academy, West Point, NY
Research Interests
Professor Dehn's research primarily examines the relationship of international to U.S. law in the areas of military, criminal and national security law. He is also examining developments in international law related to threats posed by non-state actors. His scholarship includes comparative and interdisciplinary work.
Professional/Community Affiliations
Member, Editorial Committee, Journal of International Criminal Justice
Editorial Board, Public Integrity
Courses Taught
Constitutional Law
Use of Force in International & Domestic Law
"Othering" in the Law of Nations
Public International Law
Humanitarian Law and Conflict
Humanitarian Law in Practice
Criminal Law
Criminal Procedure: Investigations
Publications/Research Listings
The Good Officer: President Trump, General Milley, and the “Necessity” of Constitutional Fidelity, (2024)
Emerging Transnational Self-Defense Norms & Unrealized Liberal Values in BETWEEN CRIME AND WAR (2022) (Oxford University Press, Claire Finkelstein, et. al., eds.)
51 Loyola U. Chi. L.J. 485 (2019)
, 59 WM. & MARY L. REV. 813 (2018)
, 102 CARDOZO L. REV. 2089 (2016)
Whither International Martial Law: Human Rights as Sword and Shield in Ineffectively Governed Territory in THE THEORETICAL BOUNDARIES OF ARMED CONFLICT AND HUMAN RIGHTS (Jens Ohlin, ed. 2016)
, 54 HARVARD INT’L L. J. ONLINE 84 (2013)
, 83 Temple L. Rev. 599 (2011)
, 159 U. PA. L. REV. PENNUMBRA 175 (2011) [debate with Kevin Jon Heller]
, 110 COLUM. L. REV. SIDEBAR 73 (2010); Response to: Trevor W. Morrison, Stare Decisis in the Office of Legal Counsel, 110 COLUM. L. REV. 1448 (2010)