Humanitarian Risk and Emerging Military Technologies: The Role of Legal Weapon Reviews in European Defence Procurement

Abstract

Europe’s rapid rearmament in response to renewed geopolitical tensions and evolving security threats has led to unprecedented public investment in defence capabilities and dual-use technological innovation. Emerging military technologies, including artificial intelligence, autonomous systems, advanced surveillance tools and hybrid warfare capabilities, are increasingly developed within complex innovation ecosystems involving private defence contractors, commercial technology firms, research institutions and public authorities. While these ecosystems enable rapid capability development, they also raise acute humanitarian concerns, as technological trajectories may become locked in before meaningful legal and ethical assessments are conducted. In this context, publicly funded defence innovation risks contributing to military capabilities that increase the likelihood of civilian harm and loss of human life, creating accountability gaps in the responsible governance of military power. International humanitarian law (IHL) provides one of the few binding legal frameworks aimed specifically at preventing such humanitarian harm. Article 36 of Additional Protocol I obliges states to review the legality of new weapons, means and methods of warfare in order to ensure their use complies with IHL. Yet in practice, legal weapon reviews are often conducted at discrete and relatively late stages in the development or operational cycle of new military technologies. As defence innovation increasingly unfolds through distributed, iterative and commercially driven research pipelines, legal review may occur too late to influence design choices or to prevent public investment in capabilities whose use could foreseeably result in unlawful or excessive harm to civilians. This temporal mismatch weakens the protective function of Article 36 in an era of accelerated and market-oriented defence innovation. Against this background, this paper argues that public procurement and defence-related innovation funding frameworks should be reconceptualised. Besides their procedural nature ensuring transparency, competition and value for money, they also serve as strategic governance instruments capable of embedding humanitarian risk awareness ex ante within defence innovation processes. Drawing on international humanitarian law, public procurement regulation and responsible research and innovation (RRI) scholarship, the paper explores how Article 36 legal review logic can be integrated upstream into procurement rules, tender specifications and research funding conditions at the European level. Such an approach would also have important implications for private and public defence actors involved in innovation and procurement processes. While Article 36 obligations remain formally binding on states, conditioning access to defence markets, public contracts and innovation programmes on demonstrated IHL-compliance readiness would create indirect but structured incentives to mitigate humanitarian risk at the design and development stage. In this way, procurement governance can operate as a channel through which humanitarian and legal principles shape technological trajectories, aligning emerging military technologies with broader societal expectations concerning the protection of human life.