Autonomous Weapon Systems, Drone Swarming and the Explosive Remnants of War

68 Pages Posted: 6 Feb 2018

See all articles by Maziar Homayounnejad

Maziar Homayounnejad

King's College London - Dickson Poon School of Law, Department of War Studies

Date Written: December 6, 2017


Lethal Autonomous Weapon Systems (LAWS) are essentially weapon systems that, once activated, can select and engage targets without further human intervention. While these are neither currently fielded nor officially part of any nation’s defence strategy, some States and defence contractors are currently developing LAWS for future deployment. In particular, swarming munitions have garnered a great deal of interest. These will consist of dozens, hundreds or (potentially) thousands of micro-drones that will operate collaboratively and as a coherent whole, to outsmart, saturate and overwhelm enemy defences. The aim is that even in the face of counter-measures and heavy defensive fire, at least a few ‘leakers’ will get through to take out their target. Yet, the flipside of such a weapon system is that large numbers of ‘non-leakers’ will succumb to defensive fire and will remain on former battlefields. Should they fail to explode as intended, these micro-drones will very likely become explosive remnants of war (ERW) and will pose a danger to civilians; one that will weigh more heavily on young children, especially in view of the munitions’ striking resemblance to toy aeroplanes.

After some introductory remarks, the following article will provide both a critical analysis of the LAWS ERW problem and a legal commentary of the potential application of three treaties. Specifically, the article will: present the ERW problem at a glance; reiterate a working definition of LAWS; describe some weapon systems likely to emerge as LAWS, focusing on swarming munitions; frame both the LAWS ERW problem, as well as some potentially mitigating assumptions; then it will comment in detail on the potential application of Protocol V to the Convention on Certain Conventional Weapons (CCW); the Convention on Cluster Munitions; and Amended Protocol II to the CCW (Amended Mines Protocol). Between these three instruments, there is the potential to stipulate: post-conflict remedial measures; generic preventive measures; and ex ante design stipulations. In some instances, the norms may be directly transplantable, while in others they may need to be adapted, to account for the peculiarities of swarming munitions. Furthermore, as Protocol V has general application to all explosive ordnances that become ERW, it may be directly applied to swarming munitions (that is, in the absence of any legislative efforts) on the proviso that its caveated drafting is interpreted narrowly to account for the advanced technical features we may expect to see in LAWS munitions. A similar situation of direct applicability may also be true of the Convention on Cluster Munitions, depending on how swarming munitions are launched.

This is the third of a seven-part series, which comprises: 1) assessing the sense and scope of autonomy; 2) whether and how LAWS can be designed/deployed in compliance with IHL; 3) issues relating to the explosive remnants of war (current article); 4) the lawful use of LAWS for targeted strikes; 5) legal and policy issues in the autonomous delivery of nuclear weapons; 6) arms control issues; and 7) non-proliferation.

Keywords: International Humanitarian Law, Autonomous Weapon Systems, Drone Swarming, Explosive Remnants of War, Convention on Cluster Munitions, Protocol V to the Convention on Certain Conventional Weapons, Amended Protocol II to the Convention on Certain Conventional Weapons

Suggested Citation

Homayounnejad, Maziar, Autonomous Weapon Systems, Drone Swarming and the Explosive Remnants of War (December 6, 2017). TLI Think! Paper 1/2018. Available at SSRN: or

Maziar Homayounnejad (Contact Author)

King's College London - Dickson Poon School of Law, Department of War Studies ( email )

London, England, WC2R 2LS
United Kingdom

Here is the Coronavirus
related research on SSRN

Paper statistics

Abstract Views
PlumX Metrics