RESPONDING TO SEPTEMBER 11:

THE FRAMEWORK OF INTERNATIONAL LAW

Parts I - IV

Interights is very grateful for the insights and comments of its board members and others, although the views expressed here are those of Interights only.

A version of this paper with full footnotes is available on request from Interights.

This paper forms part of a fuller study forthcoming from Interights.

PART I: INTRODUCTION 

PART II: PEACEFUL RESOLUTION OF DISPUTES AND USE OF FORCE

    THE OBLIGATION TO RESOLVE BY PEACEFUL MEANS

    USE OF FORCE

        Self Defence
                 Unilateral or collective
                 Conditions for self defence
                        Armed attack
                                Anticipatory Self Defence;
                              Defence of Nationals
                              State v. individual responsibility for the Attack
                        Necessity and Proportionality
                        Security Council takes over
                  Reprisals distinguished from self defence

          Security Council: International Peace and Security

PART III STATE RESPONSIBILITY

         State Responsibility in International Law
                 Effective or Overall Control
                 A Grey Area? Toleration or Encouragement

PART IV INTERNATIONAL CRIMINAL LAW AND THE JUSTICE PARADIGM

    A. INDIVIDUAL RESPONSIBILITY

        CRIMES UNDER INTERNATIONAL AND NATIONAL LAW
                  Crimes against humanity
                             Murder And Inhumane Acts
                             Widespread or systematic attack
                                     Disjunctive test
                                     Definition
                                     �Widespread�
                                     �Systematic�
                            Attack against the civilian population
                            Link to Armed Conflict
                  War Crimes
                   Terrorism
                   Other Crimes: Hijacking; �Common Crime�

           DIRECT AND INDIRECT INDIVIDUAL CRIMINAL RESPONSIBILITY

      B. JURISDICTION TO PROSECUTE

             National Courts
                  International alternatives

    C.  IMPLEMENTING JUSTICE

PART I: INTRODUCTION (top)

It is in times of greatest strain that legal boundaries are most important. The shocking attacks of 11 September 2001 (�September 11�) took place, not in a normative void, but against a backdrop of established international law and developing international practice in addressing atrocities. So far as the international response to 11 September disregards that law, the implications for human rights are potentially grave, not only in the present situation but for the future. Excepting the current situation from the framework of international law will discredit and undermine the universality of the rule of law, laying the foundation for future violations.

This paper seeks to set out in brief the law governing possible responses to September 11, highlighting areas where the law is unsettled. It does not address the facts, nor advocate any position beyond the application of international law, as set out above. The aim is to provide a resource for others grappling with the many legal questions raised by the current situation. These include: Whether and in what circumstances is the use of force a permissible response to these atrocious events? Can individuals be held to account for these acts, and if so where and under which law? Were the acts of September 11 crimes against humanity? What is �terrorism� and when is a state responsible for it? Can a state be held to account for the acts of an individual? If force is used, what protections exist for persons caught in armed conflict?

The scope of this paper is limited to the legal framework that ought to govern any response to the September 11 attacks vis-�-vis those responsible for them. Part II begins with the basic principle of peaceful settlement of disputes and the prohibition on use of force, then explores the exceptions to this rule: the circumstances in which force may be deployed and the conditions imposed on its use. Part III considers the circumstances in which acts of individuals become attributable to a state, under the rules governing state responsibility, and the consequences for such states. Turning to focus in more detail on the peaceful means of dispute resolution, Part IV considers the model of international criminal law enforcement. It assesses the crimes that may have been committed, where jurisdiction might be exercised and how the criminal law paradigm might be enforced against individuals who are responsible, directly and indirectly, for the attacks of September 11. Finally, in forthcoming parts, this paper will sketch out the human rights and humanitarian law applicable in armed conflict, and the obligations on states that stem from displacement due to armed conflict.

The human rights repercussions of September 11, which continue to unfold, undoubtedly go far beyond the issues covered here to include the violence and discrimination witnessed in the aftermath of September 11, as well as the civil liberties implications of potential security measures. These important issues, some of which have been addressed by others, are not within the scope of this paper.

PART II: PEACEFUL RESOLUTION OF DISPUTES and USE OF FORCE (top)

THE OBLIGATION TO RESOLVE BY PEACEFUL MEANS

In deciding how to respond to the events of the September 11, states must bear in mind the obligation, so far as possible, to resolve disputes by peaceful means. This obligation is enshrined in Art 2(3) of the UN Charter, which states:

All Members shall settle their international disputes by peaceful means in such a manner that international peace and security, and justice, shall not be compromised.

Within the category of peaceful means of dispute resolution fall traditional methods directed towards addressing state rather than individual responsibility, which are not addressed in detail in this paper. Suffice to note that these include arbitration, judicial settlement, non-adjudicatory methods such as negotiation, good offices, mediation, conciliation or inquiry, and settlement under the auspices of the UN or regional groups. The International Court of Justice (ICJ), as the principal judicial organ of the UN, is empowered to determine infringements by one state of the rights of another, order provisional measures to prevent or discontinue such violations, and advise states on the correct interpretation of the law in the event of uncertainty. However, its reputation for slow proceedings and lack of independent enforcement authority are seen to undermine its utility in situations of urgency.

In addition to these traditional methods, where the wrong amounts to criminal conduct, individuals may be brought to justice. As discussed in Part IV, persons who are directly responsible for a crime or, in certain circumstances, indirectly responsible for failing to prevent it, can be brought to justice before national courts or international tribunals for their part in the commission of national and/or international crimes.

The question of the lawfulness of the use of force, discussed below, should only arise in circumstances where there are no peaceful means at the aggrieved states� disposal, or where such means have been exhausted or found to be ineffective.

THE USE OF FORCE

This section sets out relevant law on the question whether, and if so in what circumstances, states are entitled to resort to the use of force under international law. The legality of the use of force under international law is referred to as the �jus ad bellum�.

The current rules governing the lawfulness of the use of force are contained in the UN Charter and customary international law. The advent of the UN Charter represented a moment of legal metamorphosis, when traditional legal concepts such as the �just war� and lawful reprisals were radically altered by the new law of the United Nations, which greatly restricted the circumstances in which the use of force can be lawfully deployed.

The general rule, enshrined in Article 2(4) of the UN Charter, is that the use of force is prohibited. Article 2(4) obliges all Members of the UN 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.

According to an ICJ judgment of 1986, this obligation reflects customary international law, despite the fact that state practice is �not perfect�, in the sense that States have not �refrained with complete consistency from the use of force�.�

Certain exceptions to the general prohibition on the use of force are contemplated in the Charter itself. Leaving aside the question of humanitarian intervention, which has

not been invoked in the present situation, the exceptions involve:

1. the use of force in necessary self defence, and

2. Security Council authorisation of force, on the basis that the Council determines it necessary for the maintenance or restoration of international peace and security.

Any resort to armed force should fall within one of these exceptions, as set out below.

Self Defence

Article 51 of the UN Charter provides that:

Nothing in the present Charter shall impair the inherent right of individual or collective self defence if an armed attack occurs against a Member of the United Nations, until the Security Council has taken measures necessary to maintain international peace and security�.

As the Charter�s reference to the �inherent� right of self defence reflects, Article 51 was intended to encompass customary international law. Where Article 51 lacks specificity, an understanding of its content can therefore be informed by customary law. However, customary law continues to exist alongside the Charter and, as noted below, in limited respects its content may not be identical.

Self defence is an exception to the �general duty of all states to respect the territorial integrity of other states,� and the only exception to the prohibition on the use of non-UN authorized force. As Oppenheim�s International Law notes, �[l]ike all exceptions, it is to be strictly applied.�

The characteristics of self defence are addressed below. The essence of self defence, as the term suggests, lies in its defensive as opposed to responsive or retaliatory objective. This distinguishes permissible defence from prohibited reprisal. Central to an assessment of justifiable self defence is therefore an assessment of the threat to the state, which must be imminent, and an identification of the source of the threat, to which defensive action must be directed. As discussed at Part III, where the threat derives from individuals, legitimate defensive action against states is linked to the question of attribution and the ability of the state or states to control the threat. Critically, all measures of self defence must be necessary to remove or counter the threat, and proportionate to it.

Individual or Collective Self Defence

The UN Charter enshrines the notion that self defence can be individual or collective. However, the meaning of �collective self defence� has generated considerable debate. Specifically, it is disputed whether Article 51 permits only the collective exercise of individual self defence (by states all of whom are subject to threat of attack), or empowers other states, whose interests are not affected, to support a victim state in the exercise of that state�s right of self defence. The scope of �collective� self defence may be relevant to the legitimacy of the use of force by states which were not the victims of the �armed attack� discussed below.

The majority of the ICJ in the Nicaragua case took the latter view: that a state�s interests need not be directly affected in order to exercise collective self defence, provided the injured state requests assistance. One commentator notes that this corresponds to state practice since 1945. However, that the matter remains unsettled can be seen from the strong dissenting judgment of Judge Jennings in Nicaragua, where he distinguishes self defence from �vicarious defence� and notes that �there should, even in "collective self defence", be some real element of self�.� This approach is followed by a number of other commentators.

The recognition of the collective nature of the right is reflected in various treaties, including the NATO treaty. This treaty reflects the latter view of collective self defence. Article 5 provides:

The Parties agree that an armed attack against one or more of them in Europe or North America shall be considered an attack against them all and consequently they agree that, if such an armed attack occurs, each of them, in exercise of the right of individual or collective self defence recognised by Article 51 of the Charter of the United Nations, will assist the Party or Parties so attacked by taking forthwith, individually and in concert with the other Parties, such action as it deems necessary, including the use of armed force, to restore and maintain the security of the North Atlantic area.

No autonomous right to use force is, or could be, contained in the NATO treaty or any other agreement. As this clause indicates, the lawful use of collective force, including by NATO, is limited by the UN Charter and, like the individual use of force by any state, it must satisfy the conditions for the exercise of self defence, set out below.

Conditions for the Exercise of Self Defence

The following conditions are generally considered to require satisfaction before resort to force can be justified as self defence.

Armed attack

The express language of Article 51 contemplates self defence only �if an armed attack occurs against a Member of the United Nations�. As such, according to the International Court of Justice, �[s]tates do not have a right of ... armed response to acts which do not constitute an �armed attack�. However, as noted below, the �armed attack� requirement is the most controversial of the self defence conditions, and highlights a number of areas where international law is unsettled.

While there is no accepted definition of armed attack for these purposes, it is generally (though, as noted below, not universally) considered to be an attack against the territorial integrity or political independence of a state. It has been said to signify considerable seriousness and to exclude �isolated or sporadic attacks�.

In this respect it is noted that recent Security Council resolutions 1368 and 1373 � which, as discussed below, condemn the attacks of September 11 and call for specific action short of the use of force to be taken in response - reiterate the right of �self defence.� This may presuppose that the events of September 11 constitute an �armed attack� for the purposes of Article 51 (although it should be noted that the resolutions do not in their operative clauses authorise the use of force on this basis).

Unsettled issues of law regarding the �armed attack�

Anticipatory self defence

Numerous commentators assert that in certain circumstances it is illogical or unreasonable to require states to wait until an �armed attack� has occurred to defend themselves. Despite the wording of Article 51 to the contrary, some argue that customary law contains no such armed attack requirement and that anticipatory self defence against an imminent threat is permissible. Others note the dangers of pre-emptive strikes and adhere to the view that they are unlawful, while a third view, found in Oppenheim�s International Law, is that �while anticipatory action in self defence is normally unlawful, it is not necessarily unlawful in all circumstances��

The language of the Caroline case has been widely quoted as establishing, and at the same time strictly limiting, those circumstances in which the use of self defence in anticipation of an attack might be permissible. The test established was one of necessity that was �instant, overwhelming, and leaving no choice of means, and no moment for deliberation.� As noted below, the Caroline �necessity and proportionality� test applies to any action of self defence, but it is ��even more pressing in relation to anticipatory self defence than [it is] in other circumstances.�

Defence of Nationals

Also in dispute is whether an attack must be directed against the territory or political independence of a state, or whether an attack against a state�s interests or nationals would suffice. Support in state practice and academic writing for �self defence� to cover defence of nationals abroad is limited.

While these issues have been critical in other contexts, they appear to be of less relevance to an assessment of the lawfulness of a US response to events of September 11, which have already occurred, and which took place on US territory. They may have continuing relevance for an assessment of the lawfulness of responses by other States.

State v. individual responsibility for the attack

A further unsettled issue of greater potential relevance is whether a state must be responsible for the existing, ongoing or imminent attack, for the right to self defence to be triggered. Perhaps because the international law of jus ad bellum, including self defence, was premised on the assumption that disputes and resolutions occur between states and those that act on their behalf, this question remains unsettled.

On the one hand, neither the language of the Charter nor the logic of self defence (as defending against a future threat) necessarily require proof of state involvement in an existing armed attack. Indeed the seminal Caroline case of 1837 involved non-state actors. Consistent with this, at least one writer has asserted the view that non-state actors can be responsible for an armed attack and justify coercive response.

On the other hand, numerous writers specifically assert that state involvement is necessary, and that, for self defence to be justified, acts of individuals or groups must be imputed to the state, in accordance with state responsibility. Following from this, it has been suggested that coercive action directed against a state without any responsibility for an existing or imminent attack could constitute an international wrong against that state. Other writers, and the ICJ judgment in Nicaragua, appear to assume that a state must be involved in the armed attack. As one writer notes, �the controversy centres on the degree of state involvement that is necessary to make the actions attributable to the state and to justify action in self defence.� The question of whether (and which) States are responsible for the armed attack may therefore be relevant to the lawfulness of a coercive response towards those states.

Moreover, as noted below, any attack in self defence must be necessary and proportionate, premised on a clear link between the target of �defensive action� and the threat being defended against. In addition to questions concerning the armed attack requirement discussed above, targeting state institutions absent evidence of their ability to control that threat may conflict with the necessity and proportionality principles.

Necessity and Proportionality

Necessity and proportionality are universally recognised as requirements of the law of self defence, and as having been required even before the UN Charter. The ICJ has found that these are requirements of self defence under customary law and, implicitly, the UN Charter.

For self defence to be justified, there must be an imminent threat of force or a continuing attack. Any response must be necessary to avert that threat and proportionate to it. These factors, which (unlike the armed attack requirement) are prospective as opposed to retrospective, are critical in distinguishing self defence from reprisals.

Necessity

In the Caroline case of 1837, which is broadly cited as representing customary law on this point, it was agreed by the parties that self defence may be exercised only when the �necessity of that self defence is instant, overwhelming, and leaving no choice of means, and no moment for deliberation.�

The necessity of force presupposes that all alternative, peaceful means have been exhausted, are lacking or would be ineffective as against the anticipated threat. The necessity principle is therefore linked to the �general principle � whereby States can only have recourse to military force as a last resort.�

Logically, for measures to be necessary to avert a threat, they must be capable of doing so. A relevant question in determining the right to self defence is therefore the effectiveness of any proposed measure. If measures against those responsible for an attack will increase the threat then they can hardly be said to be necessary to avert it.

As the Caroline case shows, necessity may imply a degree of immediacy. While an immediate response may not be an effective response, the longer the time lapse, the more tenuous the argument becomes as to the urgent necessity of unilateral action (as opposed to collective action under the UN umbrella).

It follows from the necessity (and proportionality) test, that self defence can only be justified where the targets of defensive action are clearly identified, such that their contribution to the threat in question can be properly assessed. For defensive action to be justified against persons or entities other than those directly responsible for an attack or imminent attack, the link between the threat and those targets must be established, as discussed at Part III.

Proportionality

Proportionality and necessity are intertwined, with proportionality requiring that the force used be no more than necessary to meet the threat presented. Consistent with the underlying purpose of self defence, to defend the state from future harm, the proportionality test should be applied vis a vis the existing or continuing threat as opposed to in respect of any prior armed attack.

Any purported justification of the use of force for self defence must therefore be based on evidence of an imminent second attack or on a continuing attack that needs to be pre-empted. An appraisal must then be made, in the light of the facts, of the necessity and effectiveness of the measures proposed to counter that threat, and whether the measures are proportionate to it.

Security Council takes over

A final requirement for self defence is that any individual or collective self defence measure must be immediately reported to the Security Council. While the ICJ found there to be no requirement under customary law to report to the Security Council, this requirement is explicit in the Charter itself and hence binding on all UN members.

Article 51 of the UN Charter provides that:

�Measures taken by Members in the exercise of this right of self defence shall be immediately reported to the Security Council and shall not in any way affect the authority and responsibility of the Security Council under the present Charter to take at any time such action as it deems necessary in order to maintain or restore international peace and security.

Reflecting this, Article 5 of the NATO treaty, which provides for the organisation to act �in exercise of the right of individual or collective self defence recognised by Article 51 of the Charter of the United Nations,� specifically provides:

�Any such armed attack and all measures taken as a result thereof shall immediately be reported to the Security Council. Such measures shall be terminated when the Security Council has taken the measures necessary to restore and maintain international peace and security.

Self defence under the Charter, as reflected in the NATO treaty, is clearly permissible only as a temporary measure pending Security Council engagement. If measures of force are initially justified, as necessary and proportionate self defence, they may still fall foul of the law if they are coupled with a subsequent failure to engage the Security Council.

Recent Security Council Resolutions 1368 and 1373 reiterate the right of self defence. The obligation of member states to report any self defence measures to the Council remains, however, on the basis of which the Council must then decide how to act for peace and security.

Reprisals distinguished from Self Defence

The legal distinction between self defence - which consists of necessary and proportionate measures to protect oneself against a future threat - and reprisals - which are responsive and largely punitive - is worthy of note. While legitimate self defence is permitted if it meets the tests highlighted above, reprisal action which does not amount to self defence is generally considered not to justify the use of force under the current jus ad bellum in international law.

In this respect the law changed considerably with the advent of the UN Charter. While earlier law allowed reprisals in limited circumstances, the general prohibition on the use of force in the Charter is on its face clearly inconsistent with retaliatory or punitive measures of force.

Specific reference to reprisals is found in the Declaration on Principles of International Law Concerning Friendly Relations and Cooperation Among States in Accordance with the United Nations Charter (1970), which provides that �states have a duty to refrain from acts of reprisal involving the use of force.� While not a binding instrument, this declaration does provide insight into the understanding of states as to the law in 1970, and in this respect has been referred to by the ICJ as relevant to assessing customary law.

Security Council: Maintenance of International Peace and Security

In situations where self defence cannot be justified, the only legitimate use of force is that authorised by the Security Council. As noted above, under the Charter, even where self defence can initially be justified, the lawfulness of the use of force ultimately turns on subsequent UN Security Council authorisation. The Security Council has broad powers under Chapter VII of the UN Charter to determine the existence of any threat to the peace, breach of the peace, or act of aggression and to take those measures it deems necessary for the maintenance of international peace and security.

Supplementing the Council�s powers to �call on� states to comply with its decisions, and its power to take non-coercive measures to give effect to its decisions, Article 42 confers on the Security Council unique powers to mandate enforcement action. Article 42 enshrines the broad power to �make recommendations, or decide what measures shall be taken�to maintain or restore international peace and security.�

In this way the Charter allows for the Security Council to invoke the use of force. However, the Security Council�s power to do so is not limitless; it is constitutionally confined to taking or authorising force in circumstances where doing so is �necessary to maintain or restore peace or security.� As with self defence, the necessity test must be assessed in light of the facts. Consistent with the principles of the UN as enshrined in Articles 1 and 2 of the Charter, one might assume that it will not be satisfied unless other measures not involving the use of force have been exhausted or deemed ineffective.

In this respect it should be noted that the Council can mandate a wide array of measures under the Chapter VII rubric of maintaining peace and security, some involving armed force and others not, as history attests. In the post cold war period, non-forceful measures have included establishment of ad hoc criminal tribunals, the imposition of a war reparations procedure, the demarcation of a territorial boundary, and attempts to force the extradition of alleged terrorists.

It should also be noted that one of the contexts in which the use of force has been mandated was to secure the arrest of suspected criminals. The unilateral use of force, even for the purpose of criminal law enforcement, is impermissible, and history indicates several examples of unilateral enforcement action by states that involved violation of the territory of other states that have been condemned. Similar enforcement action, including the power to use force, if and so far as necessary for the purpose of achieving the objective, can however be authorized by the Security Council. The possibility of invoking Security Council powers for the enforcement of criminal law is addressed at Part IV below.

If the Council reaches a decision, including under Chapter VII, all members of the UN are required by Article 25 �to accept and carry out� those decisions. Article 43 also commits all members �to make available to the Security Council, on its call and in accordance with a special agreement or agreements, armed forces, assistance, and facilities, including rights of passage, necessary for the purpose of maintaining international peace and security.�

In accordance with practice, the Security Council may decide not to take the forceful action itself, but may nominate others to do so. Numerous situations have arisen where states, regional organizations or �coalitions of the willing� have been authorised to take �all necessary measures� to give effect to the Council�s decisions. For example, Resolution 678 of 19 November 1990, one of many Security Council Resolutions handed down during Gulf Conflict, stated that: �the Security Council authorises member states cooperating with the government of Kuwait to use all necessary means to uphold and implement Resolution 660.�

The language of Resolution 678, above, which was broadly considered to authorise the use of force, contrasts with the language of the resolutions that have emerged in relation to the events and aftermath of September 11. Both Resolutions 1368 (2001) of 12 September 2001 and Resolution 1373 (2001) of 28 September 2001 classified the situation as a threat to international peace and security. Moreover, while the first resolution called on states to take measures to cooperate to bring to justice those responsible, the latter �decided� concrete, wide ranging measures that member states are therefore obliged to take. In more vague terms, Resolution 1373 also �called on� states to take other steps to prevent and suppress terrorist attacks. However, in its operative clauses it stopped short of authorising the use of force or �all necessary measures� to be taken as it has on previous occasions. The Council did however establish committees to report back to the Council, and expressed willingness to take further action if this proves necessary. The legitimacy of force therefore must ultimately depend on the Security Council subsequently agreeing to take, or to authorise, such force.

The role afforded to the Security Council by the UN Charter has been subject to criticism since its inception on the grounds, inter alia, of abuse of the veto power and consequent Security Council inertia, and has led some to call for a more expansive view to be taken of self defence. However, while these concerns have not disappeared, they are diminished in a post cold war era of relative Security Council activism.

In the particular situation at hand, if international consensus is in fact sufficiently cohesive, the inertia that has so often been caused by lack of political will and division in international opinion (at least of the permanent members) may not arise. The consensus on recent Security Council Resolutions may support the view that the Security Council is able now, if ever, to take the decisive measures it deems necessary for peace and security.

PART III: STATE RESPONSIBILITY (top)

The question of state responsibility for the events of September 11 has caused much speculation and debate. It permeates the discussion of lawful responses to September 11, and as to against whom any response should be directed.

The question is more relevant to some of the responses discussed than to others. The peaceful resolution of disputes between states by negotiation for example obviously depend on the de facto authority of the government to negotiate and ultimately deliver on agreements reached. Critically, state responsibility may also be relevant to the use of force and to determining against whom force might lawfully be deployed (Part II above). For example, on one view, a state must be involved in an on-going or imminent attack in order to justify the use of self defence against that state. By contrast, individual criminal responsibility (Part IV below) is largely unaffected by whether a state is responsible, as international criminal law does not recognise official immunities for egregious international crimes, although state involvement may be relevant to the question whether war crimes were committed.

State Responsibility in International Law

States can be responsible for international wrongs, either directly or vicariously. They are directly responsible where the wrong occurs at the hand of state officials, in which case the act amounts to an �act of state.� As explained below, where private individuals or groups with no �transparent relationship� with the state are responsible, the question is whether the state exercises �effective control� over their actions. Some question whether encouragement or even passive acquiescence in wrongs is sufficient to render a state responsible, but the law appears to indicate that this depends upon the ability of the state to prevent or control the wrong in question. It is well established that states are not strictly responsible for wrongs orchestrated on or emanating from their territory.

As one commentator has noted, �a transparent relationship between terrorist actors and the state is predictably uncommon.� Thus, states may be legally responsible although not formally linked to perpetrators, provided the legal test is satisfied, as described below. As responsibility turns on a complex evaluation of the facts, the sort of fact scenarios in which the test has been deemed satisfied, and when not, are also noted.

Effective or Overall Control

According to the International Court of Justice in the Nicaragua case, the test is whether the state or states in question exercised �effective control� over the wrongdoers.

In Nicaragua, the United States benefited from the relatively high threshold established by the Court, which found that it could not be held responsible for the acts of the Nicaraguan Contras. Although the Court found the US to have helped finance, organize, equip, and train the Contras, this level of involvement did not �warrant(s) the conclusion that these forces [were] subject to the United States to such an extent that any acts they have committed are imputable to that State.� The United States was liable for other activities where there was proof that they were the result of direct action on the part of the United States military or foreign nationals in its pay, but not in respect of the support given to the Contras. This aspect of the judgment is controversial, as seen from dissenting judgments (Jennings and Schwebel) and subsequent commentators, some of whom feel that such a high degree of state assistance should suffice to impute responsibility. Nonetheless the Nicaragua �effective control� test remains the authoritative source on the point.

A similar test has been approved and applied more recently by the ICTY. The tribunal found that different tests applied in respects of private individuals who are not militarily organised and paramilitary or similar groups, where the test was whether the state exercised �overall control� over their activities. However, the tribunal noted that where the �controlling State� is not the State where the armed clashes occur, �more extensive and compelling evidence is required to show that the State is genuinely in control of the units or groups not merely by financing and equipping them, but also by generally directing or helping plan their actions....�

In another case before the ICJ, the Court noted that subsequent approval or endorsement of wrongful acts may provide evidence of state responsibility. The ICJ in the Tehran Hostages case found that while the responsibility of Iran for the original takeover of the US Embassy in Tehran in 1979 was not proved, subsequent encouraging statements in the face of incidents including hostage taking by students, created liability on the part of the state. This case is not, however, inconsistent with the effective control test, as the Iranian state was considered capable of putting a stop to the situation and instead chose to endorse it. A significant question arising from these facts and the effective control test is therefore the extent of a state�s capability to prevent.

The rejection of strict liability for a state on whose territory crimes are orchestrated has been long established, since before Nicaragua. As the ICJ noted in the Corfu Channel case, it is impossible to conclude �from the mere fact of the control exercised by a State over its territory and waters that that State necessarily knew, or ought to have known of any unlawful act perpetrated therein nor that it should have known the authors.� It would, moreover, be anomalous to suggest a strict liability test in the current situation, potentially implicating the responsibility of the US or Germany for those who trained and organised on their territories. Likewise, simple knowledge of suspected terrorist activities, which could potentially implicate many states for failure to prevent, would not itself be enough.

A Grey Area? State Toleration or Encouragement

States are not then strictly responsible for international wrongs emanating from their territory but they are responsible for acts of individuals or groups over whom they exercise �effective control�. It has been suggested however that a difficult �grey area� remains, and that �the issue becomes more difficult when a state, which has the ability to control terrorist activity, nonetheless tolerates, and even encourages it.� This reflects international resolutions that urge states to refrain from �acquiescing in or encouraging� terrorist activity. Nevertheless, it would appear that �the traditional view is that state toleration or encouragement is an insufficient state connection�� and that the Nicaragua �effective control� test remains a valid statement of the law.

It is ultimately an issue of fact �whether the individuals concerned were sufficiently closely associated with the state for their acts to be regarded as acts of the state rather than as acts of private individuals.� In the light of current law, including Nicaragua, considerable proof of state involvement would be necessary to demonstrate state responsibility under international law.

PART IV: THE JUSTICE PARADIGM: INTERNATIONAL CRIMINAL LAW (top)

A. INDIVIDUAL RESPONSIBILITY

To the extent that the events of September 11 constitute crimes under international - or relevant domestic - law, those responsible, directly or indirectly, are susceptible to international and/or domestic investigation and prosecution.

While individual criminal responsibility under international law is not a new phenomenon, in recent years a system of international justice, with national and international components, has crystallised from the experience of addressing atrocities on the domestic and international levels. The work of the ad hoc international criminal tribunals for the former Yugoslavia and Rwanda (�ICTY� and �ICTR� or �the ad hoc tribunals�), the elaboration by consensus of the International Criminal Court (�ICC�) Statute and annexes and innovations in domestic law and practice have been the principal contributors. As a result, the international community is now armed with a detailed body of substantive and procedural international criminal law and a range of jurisdictional options to implement it.

The experience of, among others, the ad hoc tribunals demonstrates the viability of prosecutions involving complex criminal networks, including against those in the highest echelons of power and in respect of massive crimes. While investigations of crimes such as those witnessed on September 11 are a considerable task, crimes of greater scale and most likely complexity have been investigated and successfully prosecuted before, and there can be little doubt that with international political will the same is achievable in the present context.

This part highlights certain crimes that may have been committed on September 11, the courts or tribunals that have or might be afforded jurisdiction for those crimes and mechanisms that exist to ensure the enforcement of international criminal law.

Crimes under International and National Law

Crimes under international law are particularly serious violations of norms that are not only prohibited by international law but also entail individual criminal responsibility. They can be based on customary law or a binding treaty.

Customary law is binding on all states and, so far as criminal responsibility is concerned, on all individuals. Among the sources that can be looked to for the purposes of identifying the content of customary law in this field are the jurisprudence of international ad hoc tribunals, the ICC Statute and draft annexes and national court practice.

Treaties by contrast are only binding on those states party to them. Although treaties bind states, they may also, as in the case of treaties governing international criminal law, affect individuals. Consistent with basic principles of legality in criminal law, care must be taken to ascertain whether the treaty in question was �binding� on the individuals alleged to have been involved in criminal conduct. The principles of legality and non retroactivity require that the conduct was criminal, under treaty or customary law, at the time of its commission.

This part of the paper will highlight crimes that may have been committed on September 11. It will focus particularly on crimes against humanity which are prohibited and which all states may prosecute under customary law. It will also discuss the question of �terrorism� and its status under international law. While it mentions war crimes, hijacking and other domestic crimes, it does not purport to address the full range of national and international crimes that may have been committed.

Crimes against Humanity

�Crimes against humanity� consist of certain acts - such as murder, torture or inhumane acts - which form part of a widespread or systematic attack directed against the civilian population.

Although �crimes against humanity� first appear as a concept in the Nuremburg Charter of 1945, their prohibition in international law long predates the Second World War. It is now well established that crimes against humanity are crimes under customary international law, hence prohibited by all persons irrespective of nationality or national laws.

Unlike many other international crimes, such as war crimes or terrorism, this group of crimes has never been the subject of a binding convention to which reference can be made to determine specific content. However, regard can be had to the ICC Statute, the first treaty to set out comprehensive definitions of these crimes, other earlier international instruments, as well as ample jurisprudence emanating from prosecutions for crimes against humanity.

Key elements of the definition of crimes against humanity are referred to below.

Murder and inhumane acts

It is uncontroversial that murder and inhumane acts are among the acts that may amount to crimes against humanity under customary law. Murder is a familiar term in domestic laws, and has been held in an international context to consist of killing with �an intention on the part of the accused to kill or inflict serious injury in reckless disregard of human life.� �Inhumane acts,� a broad term found in various international and domestic laws, covers the infliction of severe bodily harm and serious �cruel treatment.�

Widespread or systematic attack

The distinguishing feature of crimes against humanity is that they must be �widespread or systematic�. While this threshold has not always been considered necessary for crimes again humanity, recent developments have confirmed that it is now a requirement, and the majority of writers appear to accept that under current international law crimes against humanity must be widespread or systematic.

It should be noted that the conduct of the particular perpetrator need not be �widespread or systematic.� Even a single act by a perpetrator may constitute a crime against humanity, provided it forms part of a broader (widespread or systematic) attack or campaign. Conversely, the acts in question may themselves constitute the attack; there is no requirement of a separate or pre-existing attack.

A disjunctive test

The requirement that the occurrence of crimes be widespread or systematic is a disjunctive one. The attack need not be both widespread and systematic. Either of the two alternatives suffices, although �in practice, these two criteria will often be difficult to separate, since a widespread attack targeting a large number of victims generally relies on some form of planning or organisation.�

Definition of widespread or systematic

There is no one source that identifies a precise definition of these terms under customary law. The ICC instruments do not define the terms. However, they have been considered and applied in numerous cases by the ICTY and ICTR. As formulations vary somewhat within the jurisprudence, perhaps reflecting in part the particular factual circumstances to which they were applied, the key aspects of that jurisprudence are set out below.

It is clear that both the concepts �widespread� and �systematic� are intended to import a considerable element of seriousness, and to �exclude isolated or random acts.�

                �Widespread�

The �widespread� requirement may be satisfied in a range of ways. Most commonly, the term is understood to refer to the scale of the crime. An earlier formulation of this criterion referred to �large scale� instead of �widespread�, defining it as �meaning that the acts are directed against a multiplicity of victims.� Following this approach, the ICTY has stated that �widespread�refers to the number of victims,� and has defined the term as meaning acts committed on a �large scale� and �directed at a multiplicity of victims.� Consistent with this, the term as used in the ICC Statute has been described as follows: �[t]he term widespread requires large-scale action involving a substantial number of victims��

While scale will often involve a series of acts, it need not, as �widespread� refers also to the magnitude of the crime. One single egregious act of sufficient scale or magnitude may suffice. As the ICTY noted, a crime may be �widespread� by the �cumulative effect of a series of inhumane acts or the singular effect of an inhumane act of extraordinary magnitude.�

The ad hoc tribunals� jurisprudence therefore indicates that �widespread� does not necessarily imply geographic spread. This is supported by a finding in one case that crimes against humanity had been committed against part of the civilian population of just one town.

�Systematic�

With regard to the requirement of �systematicity,� several cases have held that this can be satisfied by the repeated, continuous nature of an attack, a �pattern� in its execution or the existence of a plan or policy behind an attack. Consistent with this, it has been noted that the term �systematic� in the ICC Statute ��requires a high degree of orchestration and methodical planning.�

In one recent decision, the ICTY drew these factors together, noting that any of the following may provide evidence of a systematic attack: (1) the existence of a plan or political objective; (2) very large scale or repeated and continuous inhumane acts; (3) the degree of resources employed, military or other; (4) the implication of high-level authorities in the establishment of the methodical plan.

Attack against the Civilian Population

The ICC Statute imposes an additional threshold not found elsewhere in international law. As such, it is unlikely that this definition would be considered customary international law and it may not be essential for an assessment of whether the events of September 11 amount to crimes against humanity.

If, however, the ICC formulation is taken as the appropriate one, then the incidents would also have to be deemed to involve a �course of conduct�, �multiple acts� and be pursuant to a �policy� behind the attacks, in addition to being either widespread or systematic. Even according to this definition, crimes of humanity do not depend on the acts being attributable to a State. If the ICC standard is accepted, however, there must be a �state or an organisation� with a policy to commit an attack. Note however that the �policy� need not be formalised and may be inferred from all the circumstances.

Finally, it is well established that the attack must be directed against the civilian, as opposed to a military, population. Different considerations may therefore arise as between clearly civilian targets, such as the World Trade Center in New York, and those that may have a military role, such as the Pentagon.

Link to armed conflict

Crimes against humanity can be committed in times of armed conflict or in times of �peace�. While crimes against humanity originated as an extension of war crimes, the idea that such crimes can only be committed in times of war has been unequivocally rejected through developments since Nuremberg.

War Crimes

This section is relevant to the question the events of September 11 might amount to war crimes, otherwise known as serious violations of the laws and customs of war.

As the name suggests, war crimes must take place in war or armed conflict. Prosecution of those responsible for September 11 for war crimes, unlike for crimes against humanity, would have to be premised on these events amounting to the initiation of armed conflict. The ICTY definition of �armed conflict� holds that:

�an armed conflict exists whenever there is a resort to armed force between States or protracted armed violence between governmental authorities and organized armed groups or between such groups within a State. International humanitarian law applies from the initiation of such armed conflicts�

While this definition was thought to be broad-reaching, the events of September 11 do not fit readily into either category of conflict. If a state is responsible for the resort to armed force - which would have to be established according to the �effective control� test- then September 11 may amount to the initiation of international armed conflict between states. If so, the acts of violence may amount to grave breaches of the Geneva Conventions, which consist of certain very serious crimes, including �wilful killing�, committed in international armed conflict against protected persons such as civilians, which any state may prosecute.

If state control is not established, the question arises whether this is an �internal� conflict between governmental authorities and groups within a state. If, in the circumstances, the conflict is not considered to emanate from groups �within a state� (and not therefore to amount to an �internal� conflict), it may be that the events of September 11 highlight a new hybrid type of armed conflict - between organised groups and foreign States. The law governing such a scenario is unsettled. It is unclear, for example, whether such armed violence would have to be �protracted� - as set down by the ICTY to distinguish internal conflicts from civil unrest - in order to distinguish conflict from isolated attack. As it has before, humanitarian law may evolve to encompass this hybrid type of conflict.

If there is an armed conflict, as opposed to a lesser level of sporadic violence, the basic principles of international humanitarian law, including accountability, must apply. War crimes are those serious violations of international humanitarian law which entail under customary or conventional law the individual criminal responsibility of individuals. They include crimes relating to the conduct of hostilities, such as deliberate attacks on civilians or the use of weapons that cause unnecessary suffering, and crimes against protected persons, such as torture or cruel treatment carried out against person taking no part in hostilities.

Navigating these unchartered waters may, in any event, be unnecessary if other crimes were committed, such as crimes against humanity (defined above) or crimes under domestic law, and an appropriate forum has jurisdiction. One obvious issue that deserves consideration in the light of September 11 is terrorism, addressed below.

Terrorism

There is no accepted definition of �terrorism.� The issue has long been the focus of international attention, resulting in a proliferation of agreements relating to the issue. However, international consensus has never been achieved on a precise definition of what constitutes �terrorism� and who can be responsible for it. As the Special Rapporteur on �Terrorism and Human Rights� has noted in her report of 27 June 2001, the dispute over what constitutes terrorism reflects in part the hackneyed saying that one person�s terrorist is another�s freedom fighter, as well as the intractable question of which actors can be responsible for terrorism � and specifically whether it can include state actors.

Consistent with the cardinal principles of legality and certainty in criminal matters, it is difficult to see how terrorism, as yet undefined, could be said to constitute a crime of customary international law, justifying criminal prosecution on that basis. However, certain commentators do assert that customary law prohibits terrorism, despite differences as to definition, and confers universal jurisdiction to penalise and prosecute the crime.

Terrorism is defined as a crime in certain treaties that are binding on the states party to them and which, in certain circumstances, oblige particular states parties to exercise jurisdiction over the crimes covered. There are in fact no less than nineteen international conventions dedicated to terrorism in various forms. Were a prosecution to proceed solely on the basis of a treaty, complex issues may arise, including questions of how that treaty became applicable to the individual. However, where the treaty has been incorporated into domestic law of a state with jurisdiction, such as the state on whose territory a crime is committed, this issue is avoided. The United States has enacted such legislation, for example in the Antiterrorism Act of 1990, which, it has been suggested, could provide a basis for prosecution for �terrorism� offences in the US.

Finally, it is noted that terrorism was eventually omitted from the ICC�s jurisdiction on the basis of the lack of an accepted definition. However, �terrorist� conduct may still amount to a crime against humanity or any other crime in the Statute, provided it meets the criteria set down for those crimes, as discussed above.

Other Crimes:

Hijacking

Other treaty crimes may also be relevant and, as with terrorism, provide a basis for prosecution. Specifically, there are a number of conventions relating to hijacking, some of which oblige state parties to exercise jurisdiction over suspects in specified circumstances. Like the terrorism conventions, certain of those relating to hijacking have been incorporated into United States domestic law and the U.S. has in the past exercised jurisdiction in a number of cases on the basis of those treaty provisions as incorporated into domestic law.

Common Crimes

Finally, it should be noted that murder, whether as a crime against humanity or not, is a crime in most domestic jurisdictions, including the United States. While perhaps not reflecting the egregious nature of the events of September 11, it remains an option to prosecute in a domestic court as a common crime. As noted in the discussion on universal jurisdiction, below, as a crime that attracts such jurisdiction, all states should be able to exercise their jurisdiction over the events of September 11 simply on the basis of the prosecution of mass murder.

Direct and Indirect Individual Criminal Responsibility

If the events of September 11 amount to crimes under international law, then the perpetrators, direct and indirect, can be held responsible. Under international criminal law, direct responsibility attaches to those who order, plan, instigate, aid and abet, or contribute by acting in �common purpose� or in a common criminal enterprise with others for the commission of a crime. Those directly responsible are not only those who hijacked the planes, who killed themselves in the process, but also the full networks of persons who assisted in various ways. While national laws vary considerably as to principles of criminal law and terminology used, they tend to encompass a similar range of forms of participation incurring criminal responsibility.

Much attention has been focused on the need for a response to the September 11 events that reaches those �behind the attacks� including those at the highest levels. In this respect, it is important to note that in law certain people may be responsible not only for what they do � such as ordering or instigating crimes - but also in certain circumstances for what they fail to do under the doctrine of superior responsibility. A military commander or a civilian in a position of authority may be liable if he or she knew or should have known that the crime would be committed and failed to take necessary and reasonable measures to prevent it. This form of liability applies not only to those with formal legal authority, but also superiors according to informal structures, such as paramilitary leaders.

As the experience of the ICTY and ICTR testifies, this can be an extremely important basis of liability, where access to evidence of high level orders that would link those in the highest echelons with the crime in question proves elusive.

B. JURISDICTION TO PROSECUTE

International law and practice point to numerous possible venues for the investigation and prosecution of a potential September 11 case.

National Courts

International law recognises the right of certain states to exercise criminal jurisdiction. These are principally the state where the crime occurred, the state of nationality of suspects, the state of nationality of the victims and, for certain serious international crimes, all states, based on universal jurisdiction.

Consistent with these rules, the courts of the United States may provide the natural forum for prosecution, based on the fundamental principle that jurisdiction can be exercised by the state on whose territory a crime is committed. Many other states also lost nationals, in particular in the World Trade Centre attack, on the basis of which international law allows them to exercise passive personality (victim nationality) jurisdiction.

Moreover, if the events of September 11 amount to crimes that carry universal jurisdiction, under international law any state may prosecute those crimes. Customary international law has long provided for any state to exercise jurisdiction over crimes such as murder, crimes against humanity, war crimes. In addition, certain international agreements have provided for jurisdiction over these or other crimes. Other treaties, such as those relating to hijacking and terrorism, do not embrace full universal jurisdiction but do anticipate prosecution by states beyond the territorial state, such as the state of the victim�s nationality.

A growing number of states have universal jurisdiction laws in place, to ensure that they can exercise this form of jurisdiction. National courts have increasingly relied on jurisdiction to prosecute a range of crimes under international law, including crimes against humanity and genocide.

Moreover, states that do not yet have such legislation in place could even now enact legislation to confer universal jurisdiction and could prosecute in respect of September 11, provided the crimes existed at the date of commission. The cardinal human rights principle of legality and non-retroactivity in criminal law requires that the conduct be criminal at the date when it was carried out, not that jurisdiction over the conduct be established at that time.

Important developments in the practice of universal jurisdiction, of which the Pinochet case is only one, indicate that universal jurisdiction is increasingly a real international jurisdictional possibility, particularly where the territorial state cannot or will not exercise jurisdiction.

International Alternatives

If however, national courts do not want or are not able to assume the role of investigating and prosecuting, recent history provides several alternative models for investigation or prosecution of international crimes. It should be noted that the ICC is not one such model as the ICC Statute is not yet in force and the Court will, in any event, have no retroactive jurisdiction. As can be seen from the following, however, there is no shortage of possible venues for justice in this case.

The Security Council, under Chapter VII of the UN Charter has broad powers to take measures for international peace and security, as discussed previously, in Part II. In 1994 it exercised those powers to establish two international criminal tribunals for Rwanda and the former Yugoslavia. In the unlikely event of this proving necessary, it would be possible for the Security Council, which has expressed willingness to act in the current situation, to establish a tribunal or, it has been suggested, to extend the jurisdiction of an existing tribunal.

International experience also points to several hybrid models of quasi-international justice that have emerged from negotiation and agreement. Recently, an agreement between the UN and Sierra Leone lead to the Statute of the Special Court for Sierra Leone, which combines elements of national law, procedure and personnel with international components. The approach of the Nuremberg tribunal suggest that several states can together establish an international tribunal by agreement, conferring on it the power to do �what any one of them might have done singly,� namely prosecute on the basis of one of the grounds of jurisdiction mentioned above.

While perhaps an unlikely model, the Lockerbie case is also potentially relevant. The unusual model that emerged from the diplomatic impasse over the refusal to extradite suspects in the 1988 bombing was of a national court sitting on foreign soil, applying mostly national law, with the exception that there was no jury. This arose in response to the alleged inability of the Scottish courts to dispense fair and impartial justice in the particular case. This scenario could ultimately become relevant if, for example, a case were made as to the inability of the US jury system to handle this matter, given the strength of national sentiment.

C. IMPLEMENTING JUSTICE

The international criminal law enforcement model depends, naturally, on international enforcement. International cooperation with any anticipated judicial forum is essential for the purposes of, for example, arresting suspects, freezing assets and securing evidence.

A complex body of bilateral and multilateral agreements governs cooperation between states in matters of extradition and mutual assistance with criminal investigations. According to normal extradition agreements and practice, a request for extradition would be accompanied by an indictment or accusation and a showing of prima facie evidence. Absent such a procedure, a request for extradition could not be said to have been made. Even under the ICC Statute, while states are clearly obliged to cooperate with the court by transferring suspects, it is anticipated that an indictment and arrest warrant, containing �a concise statement of the facts that are alleged to constitute those crimes,� will be presented to the requested state.

It has to be noted that extradition regimes are complex, and often frought with obstacles and delays. For example, there are several grounds for refusing to extradite suspects and constitutional problems in certain states that may limit the ability to cooperate. These procedures, some of which protect important human rights, may in certain cases impede speedy justice but they are the ones provided for inter-state cooperation in current international law.

In certain circumstances, states may consider that such �cooperative� procedures are wholly inapplicable, for example where the crimes are believed to be state sponsored (as addressed by the ICJ in Lockerbie), or where the urgency of the situation demands swift action. If so, another method of enforcement can be invoked by the Security Council. The Council, whether or not it actually establishes the court that would exercise jurisdiction, can circumvent obstacles to speedy transfer of suspects by authorising enforcement action, where necessary through the use of force. Force employed must always be no more than necessary to achieve the objective, in this case the apprehension of suspects. The enforcement of arrests by the ICTY provides an example of Security Council authorisation for NATO enforcement.

The enforcement of international law is never perfect, and international criminal law is no exception. However, the unprecedented international consensus generated by the current situation, if directed towards the apprehension of suspects in relation to September 11, may provide the basis for the effective collective enforcement of international criminal law in this case.

Criminal justice enforcement represents more than a mechanism to address atrocities, it also reflects obligations under international law. International criminal law grew from the obligations incumbent on states under human rights law, requiring the investigation and prosecution of those responsible for serious crimes, with a view to establishing the truth underlying atrocious events and to provide justice and reparation.

As noted at Part II, states are obliged not to resort to force where peaceful mechanisms exist and are at their disposal. International criminal justice may provide such a mechanism.