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Autonomous weapon systems and international humanitarian law: a reply to the critics

Schmitt, M. (2013) Autonomous weapon systems and international humanitarian law: a reply to the critics. Harvard National Security Journal, 4. pp. 1-37.

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In November 2012, Human Rights Watch, in collaboration with the International Human Rights Clinic at Harvard Law School, released Losing Humanity: The Case against Killer Robots.[2] Human Rights Watch is among the most sophisticated of human rights organizations working in the field of international humanitarian law. Its reports are deservedly influential and have often helped shape application of the law during armed conflict. Although this author and the organization have occasionally crossed swords,[3] we generally find common ground on key issues. This time, we have not. “Robots” is a colloquial rendering for autonomous weapon systems. Human Rights Watch’s position on them is forceful and unambiguous: “[F]ully autonomous weapons would not only be unable to meet legal standards but would also undermine essential non-safeguards for civilians.”[4] Therefore, they “should be banned and . . . governments should urgently pursue that end.”[5] In fact, if the systems cannot meet the legal standards cited by Human Rights Watch, then they are already unlawful as such under customary international law irrespective of any policy or treaty law ban on them.[6] Unfortunately, Losing Humanity obfuscates the on-going legal debate over autonomous weapon systems. A principal flaw in the analysis is a blurring of the distinction between international humanitarian law’s prohibitions on weapons per se and those on the unlawful use of otherwise lawful weapons.[7] Only the former render a weapon illegal as such. To illustrate, a rifle is lawful, but may be used unlawfully, as in shooting a civilian. By contrast, under customary international law, biological weapons are unlawful per se; this is so even if they are used against lawful targets, such as the enemy’s armed forces. The practice of inappropriately conflating these two different strands of international humanitarian law has plagued debates over other weapon systems, most notably unmanned combat aerial systems such as the armed Predator. In addition, some of the report’s legal analysis fails to take account of likely developments in autonomous weapon systems technology or is based on unfounded assumptions as to the nature of the systems. Simply put, much of Losing Humanity is either counter-factual or counter-normative. This Article is designed to infuse granularity and precision into the legal debates surrounding such weapon systems and their use in the future “battlespace.” It suggests that whereas some conceivable autonomous weapon systems might be prohibited as a matter of law, the use of others will be unlawful only when employed in a manner that runs contrary to international humanitarian law’s prescriptive norms. This Article concludes that Losing Humanity’s recommendation to ban the systems is insupportable as a matter of law, policy, and operational good sense. Human Rights Watch’s analysis sells international humanitarian law short by failing to appreciate how the law tackles the very issues about which the organization expresses concern. Perhaps the most glaring weakness in the recommendation is the extent to which it is premature. No such weapons have even left the drawing board. To ban autonomous weapon systems altogether based on speculation as to their future form is to forfeit any potential uses of them that might minimize harm to civilians and civilian objects when compared to other systems in military arsenals.

Item Type:Article
Divisions:No Reading authors. Back catalogue items
Arts, Humanities and Social Science > School of Law
ID Code:89864
Publisher:Harvard Law School


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