Rearming Europe Responsibly: Toward Weapon Reviews in Defence Procurement Governance

Abstract

Europe’s rapid rearmament amid geopolitical tensions and disruptive military technologies has accelerated public investment in defence and dual-use innovation, raising concerns about whether such spending adequately meets legal and ethical constraints. Military capability development increasingly occurs within complex innovation ecosystems involving private contractors, commercial technology actors and iterative research partnerships, where technological pathways often solidify before traditional legal assessments apply. In this environment, public funds may inadvertently support capabilities that challenge or outpace core principles of international humanitarian law (IHL), creating vulnerabilities in the responsible governance and development of defence capabilities. Article 36 of Additional Protocol I obliges states to review the legality of new weapons, yet this legal review duty typically takes place only at discrete points in the development or operational cycle of such weapons. Accordingly, legal review may occur too late to meaningfully shape design choices or prevent investment in systems whose deployment could violate IHL. This paper argues that public procurement and innovation funding frameworks – traditionally understood as procedural mechanisms ensuring fairness and transparency – can serve instead as strategic governance tools that internalise IHL review logic earlier in defence capability development. Embedding Article 36-aligned requirements into eligibility criteria, tender specifications and R&D funding conditions would ensure that legal compliance informs technological direction from the outset rather than functioning merely as an end-stage checklist. Such a governance approach would create indirect compliance obligations too for defence contractors – private and public alike – seeking access to state funding or procurement opportunities. Conditioning participation in defence markets and innovation programmes on demonstrated IHL-compliance readiness would generate market-based incentives for responsible capability development and contribute to an ethically aligned defence industrial base. In this way, procurement becomes a mechanism through which IHL principles shape technological design and investment decisions across the defence ecosystem.