22. Under IHL, the substantive rules described above are complemented by a procedural rule. As with any other weapon, means or method of warfare, States have the positive obligation to determine, in the study, development, acquisition or adoption of any AWS, whether their employment would, in some or all circumstances, contravene existing international law. In this regard the duty to conduct legal reviews, as specified in article 36 of Additional Protocol I, constitutes an important element in preventing or restricting the development and employment of new weapons that would not meet the obligations listed above.10 Moreover, adequate testing and reviews may also have implications on the level of State responsibility, including for malfunction of approved AWS.
23. The legal review of AWS may present a number of challenges distinct from traditional weapons reviews. Specifically, the question is how such systems and their specific characteristics can be meaningfully tested. Beyond the purely technical challenge of assessing IHL compliance of an AWS, there is also a conceptual challenge related to the fact that an autonomous system will assume an increasing number of determinations in the targeting cycle which traditionally are being taken care of by a human operator. For example, in traditional systems, the principle of proportionality was to be respected by the operator. It consequently fell outside the scope of an article 36 review. However, if an AWS is expected to perform this proportionality assessment by itself, that aspect will need to be added to legal reviews of these systems. New evaluation and testing procedures may need to be conceptualized and developed to meet this particular challenge.
24. Given the special characteristics of AWS, a number of further measures could be recommended for incorporation into national review procedures. For example, one could imagine recommending that in some cases, particular safeguards against malfunction, such as the possibility of a human override, are built into AWS. Proper understanding of a system’s predictability, especially when it comes to interaction with other autonomous systems, could also be named as example. While the process of national legal reviews may require procedural and technical adaptations to fully capture the complexity of AWS, if rigorously implemented, it holds the potential of ensuring that all new weapons, means and methods of warfare are developed and acquired in compliance with international law
10 ICRC, A Guide to the Legal Review of New Weapons, Means and Methods of Warfare: Measures to Implement Article 36 of Additional Protocol I of 1977 (2006), available at https://www.icrc.org/eng/assets/files/other/icrc_002_0902.pdf.
Towards a “compliance-based” approach to LAWS: Informal Working Paper submitted by Switzerland (30 March 2016) (Informal meeting of experts on lethal autonomous weapons systems (LAWS), Geneva, 11-15 April 2016)
