Smith, Sydney --- "Evidentiary Issues Associated With Establishing Attribution In A Claim Of Self Defence: Is A Consistent Standard Of Proof Desireable?" [2021] UNSWLawJlStuS 41; (2021) UNSWLJ Student Series No 21-41

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EVIDENTIARY ISSUES ASSOCIATED WITH ESTABLISHING ATTRIBUTION IN A CLAIM OF SELF DEFENCE: IS A CONSISTENT STANDARD OF PROOF DESIREABLE?

SYDNEY SMITH

I INTRODUCTION

This paper seeks to identify and analyse the evidentiary complications which are present in establishing the element of attribution in a claim of self-defence. International adjudicational bodies have historically avoided setting an explicit standard of proof and have conjunctively avoided declaration of the standard of proof used in their judgements. This essay argues that it is time for there to be consistency and clarity in the standards of proof in international law. In exploring this proposition, this paper will look to the judgements of the International Court of Justice (‘ICJ’), attempting to identify the kinds of evidence that have been presented previously, and whether they were accepted or rejected by the court, and the standards of proof that are implicit within these judgements. The judgements of the Nicaragua and Oil Platforms cases will be examined from the perspective that they represented an emerging standard of evidence,^[1] and compared with the latter case of the DRC v Uganda which subsequently diverted from this standard and also failed to assert an alternative standard of proof.^[2] This paper will then contemplate the attribution requirement in relation to cyber-attacks and relationships between State and non-state actors, and how the changing nature of attacks impacts upon the availability of evidence and compounds the need for a consistent evidential standard. Finally, this paper will conclude that it is both practicable and desirable to apply an explicit and consistent evidentiary standard for attribution.

II ATTRIBUTION

When a State asserts a claim of self-defence it is fundamental that this State show that an attack that meets the ‘armed-attack’ threshold was directed at, and has actually occurred, against the State, and that this attack can be attributed to the State which is the intended recipient of a forceful act of self-defence.^[3] Beyond the difficulty of establishing that an armed attack has actually occurred, is the unenviable task of uncovering evidence that can trace the attack back to a particular State. Attribution is an essential element to be proved for a legitimate claim of self-defence, but what is the standard of proof?

The Articles on State Responsibility set out a framework for identifying in what circumstances a State will be responsible for an internationally wrongful act, but does not discuss an evidentiary standard for establishing State responsibility.^[4] It is stated that there will be an internationally wrongful act when conduct which can be attributed to a State constitutes a breach of international obligations of that State.^[5] Most notably, conduct will be attributed to the State where it was carried out by a state organ, no matter the organs position or function within the State,^[6] or when the conduct has been directed by, or under the control of , the State.^[7] Whilst this provides guidance on the factual question of attribution in a legal dispute, it does not clarify what standard of proof a State is required to meet when attempting to prove attribution. As has been articulated by international law scholars, we generally know which party carries the burden of proof, but we do not know exactly what that burden is.^[8]

The standard of proof must be distinguished from the rules of attribution.^[9] Whilst the rules of attribution set out when conduct will be attributable to a State, the standard of proof refers to the strength of the connection to be shown between an individual or group and a State in order for the element of attribution to be satisfied.^[10] The standard of proof refers exclusively to the character and quantity of evidence necessary to establish factual claims asserted by a party, and it is guidance in relation to this that is desperately lacking in the international arena.

EVIDENTIAL STANDARDS IN INTERNATIONAL LAW

There is no consistent standard of proof for international obligations, nor is there a clear benchmark against which the persuasiveness or reliability of evidence can be measured for the purpose of attributing State responsibility for an attack.^[11] In this sense, the ICJ has essentially unfettered power to decide what standard of evidence it will require in each case brought before it.^[12] What’s more, each international court, tribunal or arbitrator is able to set their own standards of evidence,^[13] which makes it difficult for evidential precedents to be set in international law generally. The various standards that have been applied derive from domestic law systems and are best identified by looking closely at the adjudicational body’s examination of, and commentary on, evidence in their judgements. The identified standards of proof are, the prima facie standard, on the balance of probabilities, beyond a reasonable doubt and the ‘clear and convincing’ standard,^[14] each of which will be discussed below.

The lowest of the evidential standards is the prima facie test. Essentially what this standard requires is that a State produce evidence that is indicative of the proposition claimed. For example, in the Oil Platforms case,^[15] evidence of attribution of the attack to Iran was produced by the UK in the form of surrounding mines that bore serial numbers attributable to Iran. This evidence would satisfy a prima facie standard of evidence for establishing attribution, but this evidence was rejected by the court in this instance.^[16] The court’s rejection of this evidence to prove attribution implicitly called for a higher standard of proof.

Slightly higher in threshold is the balance of probabilities or ‘preponderance’ test. This test requires that evidence establish that the factual proposition of the party relying upon it is more likely than not to be true, or have occurred. Evidence that is held against the balance of probabilities standard will have satisfied the standard when it is deemed to be more convincing than the evidence offered in opposition to it.^[17] The balance of probabilities standard is employed in many jurisdictions, including Australia, in the litigation of civil disputes. The standard of proof in the civil jurisdiction is generally lower because the nature and consequence of civil disputes are less severe than in the criminal jurisdiction.

The highest standard of evidence to have been employed is the beyond a reasonable doubt standard. With roots in the domestic criminal jurisdiction, this standard requires that a party provide evidence sufficient to leave no room for doubt in the minds of the adjudicators. Not only must it be shown that the party’s proposition is factually valid, but it must also be made virtually indisputable.^[18] This standard is utilised in criminal courts because of the gravity of matter heard, and the potential for punishment to involve the deprivation of liberty. It is warranted that there be such a high standard of proof because the nature of the matters it is applied to. Having said this, it is a standard that is often difficult to meet in domestic courts which raises questions about its practicality in the international context.

Lastly, emerging in relation to international disputes and the use of force is the clear and convincing standard, which lies somewhere between the balance of probabilities and beyond a reasonable doubt. To meet this standard a State must produce evidence that convinces the arbitrator that their factual claims are substantially more likely than not to be true. This standard does not require the virtual certainty of the beyond a reasonable doubt standard, but it is more onerous than the balance of probabilities standard in that the evidence must clearly show that a party’s proposition is supported. Not only is this standard identifiable across the judgements of international courts and tribunals, but is has also been relied upon by States in defence of their actions. For example, the United States of America has used the clear and convincing standard in public statements addressing their questionable use of force against another State. Regarding the 1986 US bombings of Libya, the US initiated attacks against Afghanistan and Sudan in 1998 and the retaliatory attack on Afghanistan in 2001, the US claimed self-defence in each instance and stated that there was ‘clear’, ‘compelling’ or ‘convincing’ evidence in support of this claim.^[19] Whilst the practice of one State does not rise to the creation of customary law, it is significant that a super-power has consistently relied upon the same standard of evidence with regard to self-defence.^[20]

The ICJ has evaded the setting of evidentiary standards for international disputes in favour of a flexible application of standards of proof. Whilst it may be desirable, and practical, to have the ability to alter evidentiary standards on a case-by-case basis, the disadvantage this poses to States must now be seriously considered. It is quite arbitrary for States to be expected to defend their actions according to a standard of evidence that does not actually exist until after litigation has occurred. At present, States must use their own discretionary powers to determine if an armed attack has occurred against them, and if there is evidence to satisfy attribution of this attack to the State they intend to take defensive action against. This essay argues that it is both practicable and necessary for rules of evidence to be established for the ICJ that deal with the standard of proof for establishing lawful acts of self-defence.

IV THE INTERNATIONAL COURT OF JUSTICE JURISPRUDENCE

The Statute of the ICJ and the Rules of Court both provide detail on the production of evidence to the court but do not require specific standards of evidence.^[21] Furthermore, neither lay out guidance as to the types of evidence the court will consider, and how probative value will be assessed in relation to different categories of evidence. Because there are no international instruments that provide guidance on evidential standards, we are left to decipher such standards from the judgements of international adjudicational bodies.

This section will analyse the ICJ judgements that dealt with self-defence matters explicitly, and how a tentative standard of proof can be seen to have been emerging. To this day, the ICJ has provided a total of three merits judgements relating directly to the use of force and self-defence. The Nicaragua and Oil Platforms judgements when read conjunctively provide the basis for identifying an emerging evidentiary standard.^[22] Although the court refrained from explicitly stating a standard of proof in their judgements, a relatively consistent implicit standard can be identified throughout both judgements. In contrast, the latter judgement of the DRC v Uganda muddied the waters by employing more than one evidentiary standard to questions of the same factual nature.^[23] Not only did the DRC v Uganda judgement fail to clarify a standard of proof expected to be provided by States asserting a claim of self-defence, but it also contradicted the standard held in precedent.

A Nicaragua and Oil Platforms

In this case, the ICJ considered whether or not attacks carried out by the Contras could be attributed to the United States. In order for the attack to be attributable to the United States, there would need to be sufficient evidence to show that the Unites States had exercised ‘effective control’ over the Contras.^[24] The court in this instance called for ‘some degree of certainty’ and stated it must be ensured that assertions by States are ‘supported by convincing evidence’.^[25] It was later asserted that there was ‘no clear evidence of the United States having exercised such a degree of control’. The language adopted throughout the Nicaragua judgement is indicative of an expectation that evidence be clear and convincing in order to be supportive of a factual contention.

Moreover, the responsibility of the United States for encouraging violations of international law was one fact in dispute which was established on the evidence. Evidence of a manual on psychological operations published by the United States was produced to the court and the court found the language within the manual, and the dissemination of the communication, to be encouragement that was likely to be effective.^[26] However, similar documentation introduced in DRC v Uganda was rejected,^[27] and through this kind of inconsistency we see a need for an established standard of proof. Furthermore, the judgement also makes reference to ‘sufficient’ and ‘insufficient’ evidence but does not attempt to articulate what would separate sufficient evidence from insufficient evidence.^[28] Despite the shortcomings of this approach, it was similarly employed in Oil Platforms.

Notably, in the separate opinions of the judges in this case concerns were raised about the absence of clear standards of evidence. Judge Buergenthal took issue with the use of labelling evidence as ‘sufficient’, asking, ‘What is meant by insufficient evidence? Does the evidence have to be ‘convincing’, ‘preponderant’, ‘overwhelming’, or ‘beyond a reasonable doubt’ to be sufficient?’.^[29] Judge Higgins extended her opinion to the responsibility of the ICJ as the principal judicial organ of the UN, opining that as a fundamental organ the court should ‘...make it clear what standard of proof it requires to establish what sort of facts’.^[30] Judge Higgins goes on to suggest that at the very least, the court should decide upon an evidential standard in each case and be explicit about what that standard is.^[31] Such harsh criticisms coming from within the ICJ’s own ranks surely implies that those of learned opinion believe a consistent standard of proof for self-defence to be achievable and necessary.

B DRC v Uganda

The judgement in this case received a lot of attention and praise when it was handed down because it was regarded as finally setting out an evidentiary standard for claims of self-defence.^[32] However, when the judgement is examined, it becomes clear that this is far from true. Whilst the court did appear to continue requiring a clear and convincing standard, it also diverted from this standard. Most concerning in these diversions was that they occurred in relation to the same factual question, being whether or not an armed attack had occurred. Because this dispute involved respective claims of self-defence, the existence of an armed attack had to be considered in multiple instances. One would think that the same evidentiary standard would, and should, be applied to questions of the same nature, but this was not the approach taken by the ICJ. The court appears to have applied different standards of evidence when looking to determine whether each attack constituted an armed attack, which once again makes a standard of proof for attribution difficult to decipher.

The ICJ in this instance devoted a large portion of their judgement to commentary on the evidence presented, the weight ascribed to various pieces of evidence and what kinds of evidence were regarded as credible, which is commendable, but unfortunately there was still no specification of a level of credibility evidence must reach.^[33] Much like in Nicaragua, the court referred to ‘sufficient’ and ‘insufficient’ evidence but did not define, or elaborate upon, what would amount to sufficient evidence. Relating specifically to attribution, the court declared that Uganda ‘had not produced sufficient evidence to show that the Zairean authorities were responsible for attacks against Ugandan territory’,^[34] but did not go on to say why the evidence was lacking, or what additional evidence would have been accepted to establish attribution.

Initially, the clear and convincing standard appeared to be applied in consistency with the previous ICJ judgements regarding self-defence. It was held that Ugandan activities in the eastern part of the DRC needed to have been ‘convincingly established by the evidence’.^[35] The evidence offered in establishment of this proposition was a sketch map in combination with other circumstantial evidence, which was rejected by the court because it’s lack of clarity made it insufficient.^[36] Similarly, the court went on to reject evidence put forward by Uganda when attempting to establish that the DRC was responsible for an armed attack carried out by the Allied Democratic Forces, because it was not ‘weighty and convincing’.^[37] Uganda presented media reports of the incident, witness statements and other secondary accounts to support their contentions, but the court regarded the evidence to not have the necessary ‘quality or character’ to support Uganda’s position,^[38] and thus an armed attack was not established in this instance.

In contrast, when assessing whether or not an aerial operation, that was allegedly carried out by Uganda against the DRC in Kitona constituted an armed attack, the court appeared to use the balance of probabilities test. The court decided that the evidence need only show that the aerial attack was more likely than not the responsibility of Uganda.^[39] This assessment of evidence set a lower standard of proof than elsewhere in the judgement. Furthermore, when assessing the responsibility of Uganda for armed attacks perpetrated by the Mouvement de Liberation du Congo, the court found that there was enough prima facie evidence to establish a breach of international law, but not attribution.^[40] Although attribution was not established by evidence satisfying a prima facie standard of proof, it is significant that the court accepted this standard of evidence in the finding of responsibility for internationally wrongful acts more generally.

Essentially, the court applied the clear and convincing standard of proof to their assessment of evidence regarding the attacks in the eastern part of the DRC, and the attacks against Uganda by the Allied Democratic Forces, but adopted a lower standard, nearer to preponderance, in the assessment of the actions of the Mouvement de Liberation du Congo and the aerial operation at Kitona.^[41] Each incident was being examined to determine whether or not it constituted an armed attack attributable to a State, yet the standard of proof was not consistent. It seems arbitrary in this sense that the ICJ assess comparable factual disputes according to different evidentiary standards.^[42] For these reasons, there remains no clear evidentiary standard for attribution in international law, despite the implicit application of a somewhat consistent standard of proof in cases regarding self-defence.

V THE CHANGING NATURE OF ‘ATTACK’

The manner in which an attack is carried out further complicates the attribution requirement, and for this reason it is argued that a standard of proof should be established and consistently applied. The difficulties in determining whether or not an attack that meets the ‘armed attack’ threshold has occurred extend to the establishment of attribution. Gone are the days where armed troops would march across state borders, bearing their nation’s flag and carrying weapons, ready to attack. Globalisation, technological advancements and the changing relationships between State organs and private bodies have made it possible to launch an attack in many ways, and have also made it easier to disguise the origins and conspirators of the attack.

A Cyber Warfare

The anonymity afforded by computer technology makes it particularly difficult to attribute cyber-attacks to a State. Cyber-attacks in the international context have been the subject of scholarly debate for some time now, with studies focusing on the applicability of international legal norms to cyber activities, and the remedies available to victim states. However, much of the discussion has neglected to consider the standard of evidence that might be required, or achievable, for a victim state to demonstrate to the court that an unlawful cyber operation has occurred, and that is attributable to another State.^[43] To establish attribution for a cyber-attack, the computer(s) or sever(s) the attack originated from must be identified, the individual responsible for carrying out the operation must be identified, and it must be proved that this person was acting on behalf of a State.^[44] However, as with other areas of international law, it is known what elements of an attack will lead to attribution to a State, but not what standard of proof is required to prove these elements.

The cyber-attacks against Estonia in 2007,^[45] and against Georgia in 2008, highlighted the need to address attacks in this context.^[46] Both nations experienced hacking attacks that lasted for weeks and targeted government organ websites and email servers, as well as major banks and other websites.^[47] It was suspected that Russia was behind these attacks, but the evidence available was circumstantial. In the case of Estonia, there was evidence that the hacking tools used were contained in Russian chatrooms and websites and certain attacks originated from Russian IP addresses, including those of State institutions.^[48] The Estonian government commented that the attacks were suspiciously well coordinated and well-resourced to be the work of rogue hackers.^[49] Similarly, the attacks against Georgia commenced in line with the armed conflict between the Caucasian State and the Russian Federation in 2008, and continued throughout the conflict.^[50] The attacks originated from IP addresses of Russian state-operated companies and these attacks also displayed a level of sophistication that would be unusual for non-state hacking groups.^[51] But with no explicit standard of proof, at what point are we able to confidently attribute an attack of this nature to a State?

The Stuxnet attacks carried out in 2012 against Iran was allegedly the combined effort of the United States and Israel. This attack involved the use of malicious software (a worm) to disrupt the Islamic Republic’s nuclear program by causing material damage to nuclear weapons infrastructure in Iran.^[52] The allegations against these States were based on interviews by journalists with former American, European and Israeli State officials and other experts, and by the specific coding of the worm used to only target the Natanz Nuclear Facility in Iran.^[53] But once again, attribution was only alleged and all available evidence was circumstantial.

In the big picture, these attacks were relatively mild in consequence, and it can even be argued that an attack which disrupted the development of nuclear weapons was to the benefit of the international community. However, attention should be paid to the fact that in a cyber-attack it is information that can be controlled. Offending States can have the power to limit the access of the public to information and resources, and at the same time target audiences with alternative information. Moreover, critical State infrastructure such as traffic lights, air traffic controls and water supplies may be the targets of cyber-attacks and interference with such can cause immense disruption and pose a great danger to the public.

B Non-State Actors

Similarly, it is possible for States to benefit from the destructive actions of private organisations and citizen lead groups without having the conduct be attributed to the State. In Nicaragua, the nexus between the State and the non-state actor had to be incredibly strong in order for the conduct carried out by the non-state actor to be attributed to the State.^[54] Essentially, the group in question would have to be under the direct instruction and control of a State. However, since the September 11 attacks on the United States, the circumstances in which a State will be considered responsible for attacks launched by non-state actors has been wavering. Appropriately, there has been a gap identified in the law which enables a State to benefit from the acts of non-state actors, without having to risk the conduct being attributed to the State itself.^[55] Previously, the supply of weapons and funds, and training and logistical support to non-state groups would not have provided a sufficient nexus for attribution, but this is now changing.^[56] However, the standard of proof to accompany this has still not been settled. This paper argues that passive support of non-state groups by States should provide for attribution of conduct to a State, but because of the gravity of such a claim it is necessary to provide a standard of proof.

Take for example the DarkMatter group operating out of the United Arab Emirates (‘UAE’). DarkMatter purports to be a cyber security group available to be contracted by private organisations, but it utilises surveillance techniques modelled on those created by National Security Agency, launches malware and hacking attacks against those who challenge the UAE agenda.^[57] Experts in the area have long suspected that the UAE government is directing the activities of DarkMatter, but there has not been a sufficient investigation into the relationship between the cyber group and the State. The group is currently under investigation by United States authorities for its involvement in the murders of journalists and human rights activists who have been critical of the UAE regime, the incarceration of foreign dissidents and the hacking of the United Nations’ offices in New York.^[58] This example illustrates where technology and State use of non-state actors intersects. Much like the cyber-attacks described above, that are suspected to be the work of the Russian State, evidence of UAE involvement remains relatively circumstantial. But it is important to consider this example because DarkMatter clearly has substantial resources and capabilities and the support of the UAE government, whatever degree it may be, and it is operations are not limited to cyber offences. This begs questions about what kind of attacks might be launched by the group in the future, and how the UAE government’s involvement will be able to be established.

Whilst States will not always be responsible for the goings on within their borders, there does need to be a benchmark for where it can be proven that a State is responsible for the conduct of groups and individuals against other States. The due diligence obligation under international law permits for attribution to a State by way of omission or inaction,^[59] which provides guidance as to when there will be attribution, but once again there is no standard of proof discussed. As has been discussed above, the availability of anonymity and degrees of separation afforded by technology and expansive organised crime and terror networks does make it possible for States to have their aggressive objectives met without having to actually carry out the attack themselves. Therefore, the need for an explicit and consistent standard of proof for attribution is further highlighted.

WHAT IS THE DESIREABLE EVIDENTIARY STANDARD?

The difficulty in formulating a desirable standard of proof for attribution is balancing the right of a State to be free from false attribution, with the right of a State to recourse for unlawful acts against them by another State. The closest domestic law analogue to international disputes heard by the ICJ generally is the civil jurisdiction, and for this reason it is argued that the evidentiary standard be no lower than on the balance of probabilities. What needs to be considered next is the gravity of the accusations and the nature of the disputes. The ICJ maintains that the context of each individual case is an important consideration when deciding evidentiary standards and it is this argument that forms part of the ICJ’s reluctance to set a standard of proof.^[60] Whilst the context of each case is an important factor, it is still possible to apply different weight and gravity to the contextual elements of a case whilst still maintaining a consistent evidentiary standard of proof for questions of the same factual nature, such as attribution.

Though the international jurisprudence is relatively unclear, it does show favour for a clear and convincing standard of proof, and this standard appears appropriate. The clear and convincing standard is a compromise between the balance of probabilities and beyond a reasonable doubt standard, and serves to acknowledge the gravity of accusations brought before the court. The fact that this standard has developed through inter-state litigation shows that its application to international law is appropriate and adds to the legitimacy of the standard. Therefore, it is this writer’s proposition that there is a compelling argument for the implementation of a clear and convincing standard for attribution.

IS IT PARCTICABLE TO EMPLOY A CONSISTENT EVIDENTIARY STANDARD IN CLAIMS OF SELF-DEFENCE?

It is both practicable and desirable to employ and explicit evidentiary standard in the determination of attribution. A consistent evidentiary standard is achievable, and the benefits of consistency will impact both the ICJ and the States subject to its jurisdiction. As has been discussed above, it is difficult and undesirable to implement a uniform standard of proof across all international courts, tribunals and adjudicational bodies. The nature of international disputes is so unique and unpredictable that this would place onerous limitations on adjudicators, and the inflexibility would in no doubt lead to injustices for victimised States. However, it is possible to implement a standard to be applied within the ICJ specifically, and more specifically, for the purposes of establishing attribution.

Unlike domestic courts, international courts and tribunals do not have the same opportunity to create common law, because of the infrequency of litigated inter-state disputes involving attacks. Without a steady case load coming before the ICJ it is not possible to develop a strength of precedent that can be regarded as judge made law, and thus serve to fill the gap in international instruments. Furthermore, evidentiary precedent cannot be relied upon unless it is explicitly expressed within judgements. Currently, we are left to infer the approach taken by the court in relation to the assessment of evidence because the ICJ has declined to declare the standard of proof employed in previous judgements. Therefore, there is currently no authoritative guidance in place for States regarding standards of proof, and it is unlikely that such guidance will eventuate in the natural course due to the ICJ’s lack of transparency.

Employing a consistent standard of proof for attribution would not only benefit the States in enabling them to better understand when an attack can legitimately be attributed to a State, but it will also increase the credibility of the court. Transparency in the judicial process will build trust and confidence in the court and lead to more cooperative litigants and effective hearings. Through this the ICJ will be further legitimised, and greater authority will be assigned to their judgements. For example, the application of multiple evidential standards in the DRC v Congo judgement, in conjunction with the courts evasion of explicitly recognising what standards were employed, appears arbitrary and does not instil confidence in the public that the court is competent in its role.

Moreover, if a consistent standard of proof is to be applied to attribution, such as the clear and convincing standard, its introduction should be accompanied by evidentiary guidelines. To aid in the interpretation of this standard the court should provide a brief conceptualisation of the standard, examples of where the standard would have been reached in previous disputes, a list of the types of evidence the court will be seeking, and what value might be assigned to them. In order for the standard to be effective in its operation, it must be understood by the court and the States. Domestic legislation often includes rules on the use and quality of evidence, and judicial bench books to guide the court in the application of evidence and evidential standards to a case, and this can be developed at an international level. The Statute of the ICJ and the Rules of the Court govern the production of evidence to the court, but does not contain guidance on approved methods of proof, or any indication of probative value or the persuasiveness of different types of evidence.^[61] Therefore, it is practicable and desirable to employ a consistent standard of proof to attribution and this consistency will benefit both the judges that are required to apply it, and the States that are subject to it.

CONCLUSION

It is desirable, practicable and necessary that an explicit and consistent standard of proof be established for attribution in international law. As has been showed throughout the analysis of this paper, there is too much discretion and uncertainty involved in making out a claim of attribution. The variable nature of an attack in the modern context calls for clearer evidentiary standards for attribution. When considering the contextual drafting of the UN Charter, it is clear as to why these matters were not canvassed in greater detail, but legislative instruments do not need to remain static. In fact, it is the role of domestic governments to reform legislation in accordance with changing standards and circumstances so that they remain relevant and effective in their application. It can be argued that international bodies have the same responsibility.

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^[1] Military and Paramilitary Activities in and against Nicaragua (Nicaragua v. United States of America) (Merits) [1986] ICJ Rep 14; Oil Platforms (Islamic Republic of Iran v. United States of America) (Preliminary Objection) [1996] ICJ Rep 803.

^[2] Armed Activities on the Territory of the Congo (Democratic Republic of the Congo v. Uganda) (Merits) [2005] ICJ Rep 168 (‘DRC v Uganda’).

^[3] Military and Paramilitary Activities in and against Nicaragua (Nicaragua v. United States of America) (Merits) [1986] ICJ Rep 14 (‘Nicaragua’).

^[4] Responsibility of States for Internationally Wrongful Acts, GA Res 56/83 UN GAOR, UN Doc A/RES/56/83 (28 January 2002, adopted 12 December 2001) annex (‘Articles on State Responsibility’).

^[5] Ibid art 2.

^[6] Ibid art 4.

^[7] Ibid art 8.

^[8] Mary Ellen O’Connell, ‘Rules of Evidence for the Use of Force in International Law’s New Era’ Proceedings of the Annual Meeting (American Society of International Law) 100 (March 29-April 1, 2006) 44-47.

^[9] Marco Roscini, ‘Evidentiary Issues in International Disputes Related to State Responsibility for Cyber Operations’ (2015) 50(2) Texas International Law Journal 233, 240.

^[10] Ibid.

^[11] James A Green, ‘Fluctuating Evidentiary Standards for Self-Defence in the International Court of Justice’ (2009) 58(1) International and Comparative Law Quarterly 163, 165.

^[12] Ibid 166.

^[13] Ibid 165.

^[14] Ibid 167.

^[15] Oil Platforms (Islamic Republic of Iran v. United States of America) (Preliminary Objection) [1996] ICJ Rep 803 (‘Oil Platforms’).

^[16] Ibid [71].

^[17] Ibid.

^[18] Ibid.

^[19] Ibid 174.

^[20] Ibid.

^[21] Statute of the International Court of Justice.

^[22] Nicaragua (n 3); Oil Platforms (n 15).

^[23] DRC v Uganda (n 2).

^[24] Nicaragua (n 3) [115].

^[25] Ibid [29].

^[26] Ibid [256].

^[27] DRC v Uganda (n 2) [125]–[137].

^[28] Nicaragua (n 3) [159].

^[29] Oil Platforms (n 15) [41] (Buergenthal J).

^[30] Ibid [33] (Higgins J).

^[31] Ibid.

^[32] Green (n 11) 163.

^[33] Ibid 174.

^[34] DRC v Uganda (n 2) [298].

^[35] Ibid [72].

^[36] DRC v Uganda (n 2) [91].

^[37] Ibid [136].

^[38] Ibid [134].

^[39] Ibid [55]–[71].

^[40] Ibid [161].

^[41] Green (n 11) 174.

^[42] Ibid.

^[43] Roscini (n 9) 238.

^[44] Ibid 240.

^[45] Steven Herzog, ‘Revisiting the Estonian Cyber Attacks: Digital Threats and Multinational Responses’ (2011) 4(2) Journal of Strategic Security 51.

^[46] Gonzalo J Arias, ‘Are the Rules for the Right to Self-Defense Outdated to Address Current Conflicts Like Attacks from Non-State Actors and Cyber-Attacks?’ (2017) 6(11) Revista Tribuna Internacional 1.

^[47] Ibid 15.

^[48] Roscini (n 9) 235.

^[49] Ibid.

^[50] Ibid.

^[51] Ibid 236.

^[52] Ibid.

^[53] Ibid 237.

^[54] Erika de Wet, ‘The Invocation of the Right to Self-Defence in Response to Armed Attacks Conducted by Armed Groups: Implications for Attribution’ (2019) 32 Leiden Journal of International Law 91.

^[55] Ibid 193.

^[56] Ibid 103.

^[57] Joel Schectman and Christopher Bing, ‘White House Veterans Helped Gulf Monarchy Build Secret Surveillance Unit’, Reuters (10 December 2019) <https://www.reuters.com/investigates/special-report/usa-raven-whitehouse/>.

^[58] Ibid.

^[59] Ibid.

^[60] Green (n 11) 165.

^[61] Statute of the International Court of Justice, arts. 48–52; International Court of Justice, Rules of Court (adopted 14 April 1978) arts 57–8, 62–4, 71.