Collective Countermeasures in Response to Cyber Operations under International Law

Legal Issues in the Digital Age. 2024. Vol. 5. No. 3. P. 103–128.

Martynova E.

The paper examines the application of collective countermeasures — i.e., measures taken by non-injured states — as a means of cooperative non-institutionalized response to malicious cyber-enabled activities undertaken or controlled by a state. Particularly, the paper investigates: the right of the state not injured by a cyber operation to take countermeasures against the perpetrating state under current international law; and state positions towards collective countermeasures and possible grounds for the development of a more supportive attitude within states to this form of collective reaction. General research and special legal methods, as well as game theory, are employed to test the hypothesis that the concept of collective countermeasures has been gaining nascent and fragmented support by states in terms of its applicability in the context of cyber operations. The author concludes that this emerging trend reflects the general tendency of states to join forces to halt malicious activities in cyberspace and impose political and economic costs upon the perpetrators. This allows one to assume that collective countermeasures in response to cyber operations might become an expectable means of reaction by ‘like-minded’ states. Their legitimation might, therefore, be determined not only (or not so much) by the development of international law due to the practical difficulty in harmonizing positions among states on this issue at the current stage, but rather as a part of the general political trend of uniting the efforts of states to bring wrongdoers in cyberspace to responsibility.

Keywords: game theory, countermeasures, cyberspace, cyber operations, state responsibility, Tallinn Manual 2.0