Jus in Bello Necessity, the Requirement of Minimal Force, and Autonomous Weapon Systems

Abstract

In this article we focus on the jus in bello principle of necessity for guiding the use of autonomous weapon systems (AWS). We begin our analysis with an account of the principle of necessity as it entails the requirement of minimal force in Just War Theory, before highlighting the absence of this principle in existing work on the permissible uses of AWS. Overlooking this principle means discounting the obligations that combatants have towards one another in times of war. We argue that the requirement of minimal force is an important requirement for considering ethical uses of force. In particular, we distinguish between lethal and non-lethal purpose of use and introduce the prospect of non-lethal purpose of use of AWS and review a number of challenges which AWS pose with respect to their non-lethal use. The challenges arise where AWS generate unpredictable outcomes impinging upon the situational awareness required of combatants to ensure that their actions meet the requirement of minimal force. We conclude with a call for further research on the ethical implications of non-lethal uses of AWS as a necessary, preliminary step to assess the moral permissibility of AWS.

Keywords: Artificial Intelligence, Autonomous Weapon Systems, Non-lethal Autonomous Weapon Systems, Principle of Necessity, Requirement of Minimal Force, Just War Theory