He holds a Ph.D. in international law from the University of Copenhagen and was affiliated with the Danish Center for Military Studies before joining the University. He has written extensively on international law and national security. His 2009 book in Danish, Arven efter Bush: Præsidentembedet og krigen mod terror, focused on the legal legacy of the George W. Bush presidency; his 2010 book, Krigens folkeret - og international væbnet terrorbekæmpelse, dealt with the international regulation of armed counterterrorism; and his 2011 book, Antiterrorismen, retsstaten og demokratiet, discussed various international and constitutional law aspects of Danish counter-terrorism legislation.