Prof. dr. Afshin Ellian (1966) is Professor of Jurisprudence at Leiden University. He received his PhD in 2003 at Tilburg University with a dissertation on the democratic transition of South Africa. Ellian wrote extensively on topics within legal and political philosophy, such as: religious extremism, the state of exception, militant democracy and (counter)terrorism. His latest publications are Freedom of Speech under Attack, edited with Gelijn Molier (Eleven Publishing, 2015), and Legaliteit en Legitimiteit: de grondslagen van het recht (Legality and Legitimacy: the foundations of law), co-authored with Paul Cliteur (Leiden University Press, 2016). His op-eds were published in leading Dutch newspapers such as NRC Handelsblad and international titles as The Wall Street Journal and Le Figaro. Bastiaan Rijpkema PhD (1987) is Assistant Professor at the Department of Jurisprudence at Leiden University. He received his LL.B. in Law at Erasmus University Rotterdam (2010) and his LL.M. in Jurisprudence and Philosophy of Law (cum laude) from Leiden University (2011). In 2015 he obtained his PhD at Leiden University with a dissertation on militant democracy. His main interests lie in the fields of legal and political philosophy, especially democracy, extremism and free speech. In 2014 he co-authored a new edition of the 1936 inaugural lecture of Amsterdam constitutional scholar George van den Bergh on antidemocratic parties (Elsevier Books), for which he wrote an extensive introduction. His dissertation was published as Weerbare democratie: de grenzen van democratische tolerantie (Militant Democracy: The Limits of Democratic Tolerance) and was reviewed in major Dutch and Belgian newspapers. Rijpkema is a regular commentator on politics for the Dutch Radio 1 and published several op-eds on national and international politics. He is also frequently invited for expert meetings held by the Dutch government, for instance with Deputy Prime Minister Lodewijk Asscher and the Dutch Coordinator for Security and Counterterrorism.