Ensuring Lethal Autonomous Weapon Systems Comply with International Humanitarian Law

Abstract

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, there is ample evidence that many States and defence contractors are currently developing LAWS for future deployment. The main IHL problem posed by these weapon systems is that lethal action against specific targets will be taken by sensory hardware and control software, rather than human operators exercising deliberative reasoning and judgment. Commanders will exercise such reasoning, but will do so during earlier phases in the targeting cycle, and at locations further removed from the intended strike site. Accordingly, they will have less accurate knowledge of concrete threats or specific civilian risks. This may lead to unforeseen targeting errors in the field, which often bear heavily on civilians and their property. To guard against this, commanders will have to ensure that appropriate systems are deployed in a given operational environment, along with adequate precautionary measures to sufficiently mitigate civilian risk. After some introductory remarks, the following article will: reiterate both a working definition of LAWS and the kinds of weapon systems likely to emerge as LAWS; frame the LAWS IHL problem and explain how it will be addressed; provide a detailed account of the normative IHL framework and its application to LAWS, focusing on the principles of distinction, proportionality and precautions in/against the effects of attack; consider some general lessons learned from other weapons treaties, and how these may help to inform the lawful development, deployment and use of LAWS; and examine the lawful deployment and use of LAWS via the ‘meaningful human control’ concept. This latter part will be the most detailed, and will consider potential legal transplants from other weapons treaties that may help to make LAWS operations more IHL-compliant. A final section offers some concluding thoughts. This is the second 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 (current article); 3) issues relating to the explosive remnants of war; 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.