Critics of autonomous weapons systems (AWS) claim that they are both inherently unethical and unlawful under current international humanitarian law (IHL). They are unethical, it is said, because they necessarily preclude making any agent fairly accountable for the wrongful effects of AWS, and because allowing machines to make life or death decisions seriously undermines human dignity: only moral beings should make such decisions and only after careful moral deliberation, for which they could be held accountable. AWS are inherently unlawful, critics say, because they cannot possibly comply with the core IHL principles of discrimination and proportionality.

Contrary to these critics, I argue in this chapter that AWS can conceivably be developed and deployed in ways that are compatible with IHL and do not preclude the fair attribution of responsibility, even criminal liability, in human agents. While IHL may significantly limit the ways in which AWS can be permissibly used, IHL is flexible and conventional enough to allow for the development and deployment of AWS in some suitably accountable form. Having indicated how AWS may be compatible with IHL and fair accountability, I turn to a serious worry that has been largely neglected in the normative literature on AWS. The development of AWS would deepen the already ongoing and very troubling dynamics of asymmetrical and so-called riskless warfare. While IHL-compatible AWS could be developed, in principle, and agents in charge of designing, testing and deploying AWS could be held accountable for wrongful harms, there are troublingly few incentives to duly control and minimize the risks to foreign civilians in the contexts of asymmetrical warfare. The most troubling aspects of AWS, I suggest, are not matters of deep ethical or legal principle but, rather, the lack of incentives for implementing effective regulations and accountability.

The main goal of this chapter is to articulate this distinct worry and emphasize how serious it is. Once this is appreciated, it will be clear that more attention needs to be paid to determining what conditions would allow for the effective oversight of AWS development, testing and eventual use. Such oversight may be accomplished partly by defining liability criteria for agents working within the industrial and organizational complex behind AWS design, production and use. Ultimately, however, public scrutiny may be the only available effective push for IHL compliance and accountability.