Prof. Dr Hillgruber, born in Darmstadt on 9 December 1963, holds a chair in public law at the Rheinische Friedrich-Wilhelms-Universität Bonn and has been Director of the Institute for Canon Law at the same university since 2016. Since 2006, he has been a deputy member of the Constitutional Court for the State of North Rhine-Westphalia, in which office he was last re-elected in June 2018. Hillgruber focuses on constitutional law and international law as well as the philosophy of law and the theory of the state. Together with Volker Epping, he is the co-editor of the standard commentary "Epping/Hillgruber" on the Basic Law for the Federal Republic of Germany, published by C. H. Beck. He also regularly publishes guest articles for the Frankfurter Allgemeine Zeitung.