Scenario 03: Cyber operation against the power grid

Intelligence services of State B compromise the supply chain of an industrial control system in State A, thereby gaining access to a part of its electric power grid. Subsequent attacks bring down the grid, leading to prolonged blackouts. The scenario considers whether such incidents may violate, among others, the prohibition of the use of force in international relations, the prohibition of intervention in the internal affairs of States, and the obligation to respect the sovereignty of other States. Specific consideration is given to the existence of a standalone obligation to refrain from attacking critical infrastructure of other States through cyber means.

Keywords
Critical infrastructure, intervention, sovereignty, use of force

Facts
Government-owned company X is responsible for the distribution of electricity across a large part of the territory of State A. Accordingly, its infrastructure has been designated as “critical national infrastructure” by the domestic law.

Delivery of computers procured as part of the modernisation of the industrial control systems (ICS) used by company X is, unbeknownst to either of the contractual parties, compromised by attackers who succeed in installing concealed remote-control equipment in the computers in question. Once the computers are integrated in the ICS, the attackers are able to remotely monitor the activities in the technical control centre and to assume control over the infrastructure of company X without the staff knowing.

In the meantime, the relationship between States A and B, frail due to a shared history and a complicated ethnic composition of State A, whom State B periodically accuses of mistreating its large ethnic minority, significantly deteriorates. At one point, the distribution of power to tens of thousands of households in State A suddenly comes to a halt.

Initially, the technical control centre staff at company X are unable to locate the source of the problem. All reports generated by the ICS suggest normal operation. The controllers are unable to fix the problem remotely and technicians have to be dispatched to individual locations to perform a manual restart and thus to gradually restore the functionality of the network. In the meantime, the government sends its emergency responders and provides generators to the most affected residents.

As a consequence of the operation, many households are left without electricity for days, resulting in significant inconvenience for the local residents. However, the power cuts are limited to residential areas and no physical damage or personal injury is reported from any of the affected areas.

Much later, the source of the vulnerability is identified and the remote-control equipment is found and removed from the ICS at company X. Forensic analysis of the removed equipment determines that it was designed, installed, and controlled by the intelligence services of State B. State A is a member of a collective self-defence alliance O.

Examples

 * [YEAR] Black Energy
 * [YEAR] Stuxnet
 * [YEAR] Steel mill in Germany

Legal analysis
The analysis in this scenario focusses on the responsibility of State B for potential violations of international law as against State A. It assumes that the cyber operation against company X was attributable to State B. Given the facts of the scenario, this assumption is not particularly controversial. As noted, the technical investigation of the incident showed that the equipment used to compromise the grid had been installed by the intelligence service of State B. Pursuant to Article 4 of the ILC Articles on State Responsibility for Internationally Wrongful Acts, the conduct of any State organ, irrespective of its position within the State, its functions and its character as an organ within the central government or territorial unit, shall be considered an act of that State. Intelligence services undoubtedly form part of the executive power and their conduct is thus attributable to the relevant State under Article 4. Accordingly, the remainder of the analysis considers which specific rules of international law, if any, may have been breached by the operation in question.

Use of force
Article 2(4) of the UN Charter prescribes States to “refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the purposes of the United Nations”. This prohibition is reflective of customary international law and it is frequently described as a peremptory norm of international law. However, the notion of “force” in this context is limited to armed force, and to operations whose scale and effects are comparable to the use of armed force.

At present, the law is unsettled on the issue whether cyber operations with no physical effects may amount to a prohibited use of force. It has been argued that disruptive cyber operations of this kind fall under the scope of Article 2(4) if the resulting disruption is “significant enough to affect state security”. Undoubtedly, one of the purposes of the prohibition of force under international law is to safeguard the national security of the potentially affected States. However, many forms of outside interference including various forms of political and economic coercion may affect the national security of the victim State. And yet, the drafters of the UN Charter had expressly rejected the proposal to extend the prohibition of force beyond the strict confines of military (or armed) force.

Admittedly, the notion of “force”, like other generic terms in treaties of unlimited duration, should be presumed to have an evolving meaning. However, there is little State practice supporting the claim that its meaning has by now evolved to include non-destructive cyber operations against critical national infrastructure. In fact, to date no victim State of an operation of this kind has suggested that the operation would have amounted to a use of force.

Even if an operation does not meet the threshold of the use of force, it may still be considered a violation of other rules of international law. In this regard, the prohibition of non-intervention, the obligation to respect the sovereignty of other States, and the obligation to refrain from attacking other States’ critical infrastructure are all of potential relevance.

The scenario notes that the cyber operation against company X had caused significant inconvenience to many households in State A. The blackout must also have resulted in economic damage to company X and other actors on State A’s territory, likely including the State itself. However, there is no indication of actual physical damage having occurred or of any injury to individuals as a result of the operation. Therefore, the principal legal question is whether such forms of interference may be categorized as a use of force inconsistent with Article 2(4) of the UN Charter. As noted, the law is unsettled in this regard and a clear conclusion cannot be made at present.

In any event, the characterization of an incident of this nature as amounting to a use of force would be of limited consequence in the present scenario. This is because even if a particular act by a State qualifies as prohibited force, the victim State and its allies may only respond in self-defence if the said act is additionally of sufficient gravity to amount to an “armed attack”, and even then, the permitted response is further limited by the conditions of necessity and proportionality. However, the lack of destructive effects in State A strongly militates against the qualification of the cyber operation by State B as an “armed attack” under international law.

Moreover, the fact that the source of the disruption was only identified after the disruptive effects had been addressed means that at that point, it could no longer be said that a use of force in self-defence by State A or by alliance O was necessary to repel an ongoing attack by State B. Of course, State A would still be entitled to call upon the UN Security Council to qualify the cyber operation as having amounted to a “breach of the peace” and to decide on measures under Chapter VII of the UN Charter.

However, the spectrum of unilateral responses available to State A under international law is otherwise identical to those available in response to violations of international law other than the prohibition of force. It is thus arguably unnecessary to conclusively determine if the cyber operation against State A did in fact cross the threshold of Article 2(4) of the UN Charter, as long as the relevant conduct breached other applicable international legal rules. This is what the remainder of the analysis turns to.

Prohibition of intervention
The principle of non-intervention prohibits States from intervening in the internal or external affairs of other States. Prohibited intervention was authoritatively defined by the International Court of Justice in the judgment on the merits in the 1986 case Nicaragua v United States:

A prohibited intervention must … be one bearing on matters in which each State is permitted, by the principle of State sovereignty, to decide freely. One of these is the choice of a political, economic, social and cultural system, and the formulation of foreign policy. Intervention is wrongful when it uses methods of coercion in regard to such choices, which must remain free ones.

Two elements follow from this understanding. The first is that in order for an act (a term that is wide enough to include a cyber operation) to qualify as prohibited intervention, it must bear on those matters in which States are allowed to decide freely (the so-called domaine réservé of States). As the ICJ ruling explains, the spectrum of such issues is particularly broad and it includes choices of political, economic, social, and cultural nature.

The second element of prohibited intervention is that the act in question must be coercive in nature. There is no generally accepted definition of “coercion” in international law. However, as per the analysis in Tallinn Manual 2.0, the “key is that the coercive act must have the potential for compelling the target State to engage in an action that it would otherwise not take (or refrain from taking an action it would otherwise take)”.

It is unclear whether State B’s act had a bearing on State A’s domaine réservé in the present case (the first prong of the test). State A would have to establish that “the act in question [was] designed to undermine [its] authority over the domaine réservé”. If, for instance, it transpired that State B designed the operation with the specific aim to bring to an end the ethnic discrimination by organs of State A, then this would bring it within the protected sphere of matters, fulfilling the first prong of the test.

As for the element of coercion, it depends, as above, on the purpose of the operation. If it was designed to compel State A to modify its policing practice, then (whether or not this outcome was in fact achieved) the second prong of the test would have been fulfilled, too.

Obligation to respect the sovereignty of other States
Whether sovereignty has been violated in the present case is controversial. On the one hand, the outcome of the operation was limited to physically non-destructive effects and its impact on the electrical distribution grid was fully reversible. On the other hand, the operation caused significant inconvenience for the population and necessitated a degree of government response in the form of provision of supplies and aid. On balance, the better view is that operations of this kind qualify as infringing on the sovereignty of the affected State given that the need to respond deprives that State of a part of its ability to conduct its affairs freely.

Possible obligation not to conduct cyber operations against other states’ critical infrastructure
In its 2015 report, the UN group of governmental experts agreed on a formulation that “[a] State should not conduct or knowingly support ICT activity contrary to its obligations under international law that intentionally damages critical infrastructure or otherwise impairs the use and operation of critical infrastructure to provide services to the public“. This raises the question whether a cyber operation such as the one described in this scenario infringes an obligation not to attack critical national infrastructure of other States.

However, it is uncertain whether such an obligation can be said to exist in the present state of international law. Three points should be made in this regard. First of all, cyber operations against critical infrastructure have recently become a very frequent occurrence in the international practice. Of course, the frequency of particular type of conduct, even if it “amount[s] to a settled practice”, does not by itself suffice to establish a new permissive rule of customary law. However, the fact that most of these instances have not been accompanied by specific condemnations by those States in a position to react to them, suggests that equally, no corresponding prohibitive rule has emerged thus far.

Secondly, although UN GGE reports are based on the consensus of governmental experts selected on the basis of equitable geographical representation, their views cannot be said to automatically reflect customary international law. The mandate of the UN GGE is decidedly not focussed on the identification of customary legal rules; rather, it includes the proposing and promoting of “[v]oluntary, non-binding norms of responsible State behaviour”. As such, the legal valence of any normative statements found in one of the reports must be understood as minimal to none.

Finally, even if the GGE did have the mandate and ability to identify relevant rules of custom, it most certainly did not do so with regard to operations against critical national infrastructure. It is manifest from the formulation cited above that the governmental experts did not consider any intentional cyber operation against critical national infrastructure to be internationally unlawful. Rather, they included the phrase “contrary to its obligations under international law”, confirming that on their view, such an operation would only violate international law if there is an additional obligation that would be breached by the operation in question.

In sum, the preferred view is that a standalone rule prohibiting cyber operations against critical national infrastructure has not emerged in international law thus far. As such, the incident in the scenario cannot be described as infringing this supposed obligation.