18. The application of international law to the use of countermeasures in cyberspace must
take account of the nature of cyber activities, which might commence and then cease
almost instantaneously or within a short timeframe. In those circumstances, a wider
pattern of cyber activities might collectively constitute an internationally wrongful act
justifying a response.
19. The UK does not consider that States taking countermeasures are legally obliged to give
prior notice (including by calling on the State responsible for the internationally wrongful
act to comply with international law) in all circumstances. Prior notice may not be a legal
obligation when responding to covert cyber intrusion with countermeasures or when
resort is had to countermeasures which themselves depend on covert cyber capabilities.
In such cases, prior notice could expose highly sensitive capabilities and prejudice the very
effectiveness of the countermeasures in question. However any decision to resort to
countermeasures without prior notice must be necessary and proportionate to the
purpose of inducing compliance in the circumstances.
INTERNATIONAL HUMAN RIGHTS LAW
20. Human rights obligations apply to States’ activities in cyberspace as they do to in relation
to their other activities. The UK continues to support the view set out in Human Rights
Council Resolution 20/8 that ‘the same rights that people have offline must also be
protected online…’. States have an obligation to act in accordance with applicable
international human rights law, including customary international law, and international
conventions to which they are a party, such as the International Covenant on Civil and
Political Rights, other UN treaties, and regional instruments such as the European
Convention on Human Rights.
21. States’ respect for their human rights obligations in relation to their activities in
cyberspace is essential to ensuring an open, secure, stable, accessible and peaceful
environment and certain rights may have particular relevance to States’ activities in
cyberspace including the right not to be subjected to arbitrary or unlawful interference
with privacy, family, home or correspondence, the right to freedom of thought,
conscience and religion and the right to freedom of expression.
INTERNATIONAL HUMANITARIAN LAW (IHL)
22. IHL applies to operations in cyberspace conducted in the furtherance of hostilities in
armed conflict just as it does to other military operations.
23. IHL seeks to limit the effects of armed conflict - it protects persons who are not, or who
are no longer, participating in hostilities, and limits the methods and means of warfare
6