Prof. Dr. Isabelle Ley

Isabelle Ley is a Professor of Public Law, Public International Law and European Union Law at Friedrich Schiller University in Jena since October 2025. She studied law and political sciences in Heidelberg, Paris, and Hamburg. Her doctoral thesis "Opposition in International Law" deals with the question of how processes of international lawmaking can adequately reflect political and societal conflicts transcending inter-state cleavages. She received her doctorate under the supervision of Ulrich K. Preuß and Nico Krisch from Humboldt University in 2012. 
While preparing the dissertation, she was a research assistant with Georg Nolte and a visiting researcher at Hauser Global Law School at New York University. After her second state examination at the Berlin Court of Appeal in 2013 (with stages at the International Law Department of the German Foreign Office and the EU Law Department of the Federal Ministry of Economic Affairs), she worked as a senior research fellow with Anne Peters at the Max Planck Institute for Comparative Public Law and International Law in Heidelberg from 2013-2017.

She tried her luck outside of academia in 2018-2019 as a desk officer at the Federal Ministry for Economic Affairs (External Trade Department) as well as as a District Court Judge in Berlin, but was happy to return to academia later on. With funding from the Deutsche Forschungsgemeinschaft (German Research Society), she conducted research on the doctrinal and institutional framework of the German, EU and international legal rules of the international arms trade and received her venia legendi (Habilitation) from the University of Heidelberg in 2025. Her main research interests focus on German foreign relations law, EU constitutional and external action law, international courts and 
institutions in times of a changing international order, as well as judicial and academic resilience in times of democratic backsliding.

She is married and has two children.