In recent years, democratic legislatures have struggled to maintain a role for themselves in government decisions to conduct extraterritorial military operations, including those that involve the use of force. The US Congress offers a prime example of this phenomenon, but other legislatures such as the British Parliament and the French National Assembly face similar challenges. Some of these challenges are due to constitutional provisions, institutional structures and historical practice. Even constitutions that give legislatures a role in authorizing military force ex ante often empower executives to respond to sudden attacks without legislative blessing. Further, executive branches are necessarily better structured than legislatures to collect classified information, respond quickly to urgent security threats and direct military operations. Not all legislative limitations are linked to constitutional rules or structures, however.

These legislatures are also struggling to preserve their roles because of the changing nature of conflict: a shift away from large-scale, kinetic operations toward smaller-scale operations, including operations in cyberspace, that are harder to detect publicly and do not require the type of robust legislative support that large-scale conflicts do. These modern operations leave legislatures struggling to learn the facts and engaging in ex post and sometimes ineffective efforts to hold their executive branches accountable for offensive cyber operations that could lead to hostilities with other States. The introduction of increased autonomy into this setting has the potential to further alter the existing relationships between executives and legislatures in making decisions that implicate the use of force. Because the use of autonomous cyber tools may lead States into serious tensions—if not armed conflict—with other States without advance notice, these capabilities pose particular hurdles for legislatures that already struggle to stay relevant on use of force and cyber issues. Additionally, a State’s ability to employ autonomous cyber tools may alter the dynamics among different actors within executive branches themselves—by, for instance, diverting deliberative input and oversight abilities away from foreign, intelligence and justice ministries and toward defense ministries in the lead-up to conflict.

This article explores how the use of increasingly autonomous cyber tools may alter the current state of legislative oversight and internal executive decision-making about the resort to force. It also illustrates how these changes may impact international peace and security; and it identifies ways in which States may prevent a further erosion of democratic accountability for cyber-related jus ad bellum decisions. Unless legislatures take steps now to preserve a role for themselves, and unless executive branches ensure that an appropriate diversity of officials remains involved in use of force decisions, key vestiges of democratic accountability for those decisions may fall away. Executives will not wait long for their legislatures to act, given the urgency of cyber threats.

Ashley S. Deeks, Will Cyber Autonomy Undercut Democratic Accountability?, in Autonomous Cyber Capabilities under International Law, NATO CCDCOE Publications, 67–105 (2021).