Declaration of Persona Non Grata in Times of Political Confrontation: A Legal Analysis of Recent State Practices

Between December 2016 and April 2018, in a frame of escalating tensions among States not seen in years, 29 countries, including the United States of America, Russia and the United Kingdom, decided to declare persona non grata more than 300 diplomatic representatives —which accordingly had to leave the territory of the receiving State—. In this context, this article undertakes a legal analysis of persona non grata declaration. It examines whether recent State practices are coherent with conventional norms and suggests a possible progression. Also, it provides a definition and elements to discuss, categorise and understand better that legal measure.