Research page
International Law

Lethal Autonomous Weapon Systems and War Crimes: Who is to Bear Criminal Responsibility for Commission?

Timeline: July 2018 - June 2022
Keywords: international criminal law; individual criminal responsibility for war crimes; killer robots, autonomous weapons systems, war crimes, methods of warfare
Funding Organisation: Swiss National Science Foundation



Under international law individuals are criminally responsible for violations of international humanitarian law (IHL) amounting to war crimes. The rapid development of so-called Lethal Autonomous Weapons Systems (LAWS), e.g. military robots designed to select and attack military targets (non-civilian people and objects) without intervention by a human operator, raises new challenges to the principles and rules on international criminal responsibility of individuals for the commission of war crimes.

In light of the autonomy of LAWS’s decisions, there is the possibility that, once engaged in the battlefield, these weapons target peoples and objects in violation of IHL rules on the methods of warfare. Among others, the question therefore arises of whether and under which conditions the individuals who have deployed the LAWS can be held responsible for the commission of the resulting war crimes. This, in turn, requires investigating what are the legal ingredients of the relevant war crimes pertaining to the methods of warfare, focusing in particular on the requisite mental element (mens rea) and the standard to establish the casual nexus. Against this background, it will be then possible to draw conclusions as to whether the individuals who have engaged LAWS are responsible for the commission of war crimes stemming from the illegal LAWS’ targeting decisions.

The aims of this project are both descriptive and normative. Above all, the project wants to clarify whether and to what extent the requirements for ascribing criminal responsibility for commission – and in particular the key concepts of culpability theories, i.e. the mens rea and the causation – can be applied to the use of LAWS in combat operations. Given the current ‘fragmentation’ of international criminal law (ICL) the analysis will be conducted by taking into account both the international and national level. It will thus examine the statutes and case law of international criminal courts and tribunals on war crimes relating to methods of warfare, plus other relevant international instruments such as the rules on grave breaches contained in Additional Protocol I to the 1949 Geneva Conventions. As for the national level, the analysis will examine the national criminal legislation and case law of selected and representative countries, including those for which there is information that they are developing LAWS. This analysis will thus serve to identify lacunae and inconsistencies in the current legal framework in the face of the advent of military robotics.

Ultimately, the research will prompt a reflection on whether there is the need to rethink the fundamentals of ICL with respect to war crimes pertaining to illegal methods of warfare, and develop frameworks or interpretations that better reflect and encompass the novel human/machine interaction in war.