In the course of history, third States have always tried to influence the outcome of armed conflicts in one way or another. In more recent decades, they frequently do so by providing support to the parties involved that is not necessarily kinetic, but nevertheless crucially determines the evolution of such conflicts. Examples of non-kinetic (or non-lethal) support include the provision of air-to-air refuel services, the sharing of crucial intelligence information or allowing territory to be used for launching drone operations. Under jus in bello and jus ad bellum, such support potentially triggers different legal consequences by reaching one of the various thresholds developed in those bodies of law. For instance, the supporting States could become party to an armed conflict (a jus in bello consequence), or their support could trigger a reaction in self-defence by another State (a jus ad bellum consequence). The exact meaning of the various jus in bello/jus ad bellum thresholds remains however subject to debate.

This seminar focused on one of the ‘alternative’ thresholds in jus in bello that have been developed to deal with State support to parties to an armed conflict. In order to decide whether such States become party to a pre-existing armed conflict (and more specifically a non-international armed conflict (NIAC)), the International Committee of the Red Cross (ICRC) has introduced the so-called ‘support-based approach’. Under this approach, a supporting State would not need to reach the normal intensity requirement of a NIAC if its support is provided to a party to the NIAC and related to the conduct of hostilities. In essence, this approach lowers the traditional threshold for State to become a party to a NIAC. After introducing the approach, Nele argued that for several reasons the scope of the support-based approach should be broadened. Subsequently, however, the risks of a (broadened) support-based approach was explained, inter alia, by linking it to various thresholds under jus ad bellum.

Nele Verlinden is a a Kathleen Fitzpatrick Visiting Fellow in the Laureate Program in International Law at Melbourne Law School in 2017. She is a PhD candidate at the Leuven Centre for Global Governance Studies of the University of Leuven, Belgium. She holds a Master of Laws degree from the University of Leuven and an LL.M from the Geneva Academy for International Humanitarian Law and Human Rights. Previously Nele worked as legal advisor to the International Committee of the Red Cross, Geneva. Her research is supported by the Research Foundation Flanders (FWO).