ABSTRACT
States, as primary actors of international law, have consistently aimed to establish and maintain their national defense mechanisms at both national and international levels. In pursuit of this objective, they have formed armies under their direct authority and exercised full control over them. However, over time, whether due to international or non-international armed conflicts, states have faced the need for additional personnel to strengthen their defense capabilities and, when necessary, respond to attacks. Furthermore, even in situations where their own national security is not directly threatened, states consider themselves authorized and responsible for contributing to the maintenance and restoration of international peace and security.
Beyond states, the United Nations (UN), established in 1945 through the collective agreement of states and recognized as the most significant universal international organization, has likewise adopted the objective of maintaining international peace and security. Pursuant to Article 1 of the UN Charter, this constitutes the UN’s primary purpose. Indeed, under Chapter VII of the UN Charter, the United Nations is vested with broad powers to restore international peace, security, and stability in cases where these are threatened or breached. Moreover, Articles 22 and 29 of the UN Charter authorize the General Assembly and the Security Council to establish the necessary subsidiary organs to ensure international peace and security. Although the UN does not possess its own standing army, these provisions have given rise to the concept of “UN peacekeeping forces,” whereby temporary operations are conducted in relevant regions to maintain or restore peace and security.
As an international organization rather than a state, the United Nations does not inherently maintain an army. Therefore, to preserve or re-establish global peace and security, it requests member states to contribute military personnel to peacekeeping operations. Nevertheless, it has been observed that states already making use of private military and security companies (PMSCs) increasingly prefer to deploy private personnel through such companies rather than members of their national armed forces for UN peacekeeping operations. Consequently, PMSCs have assumed a growing role, particularly in logistical and support functions within UN operations. However, the involvement of PMSCs in UN peacekeeping missions has generated certain legal challenges that cannot be fully addressed by traditional international law, thereby giving rise to new debates.
Mercenaries are defined under Article 47 of Additional Protocol I to the Geneva Conventions and are not entitled to combatant or prisoner-of-war status. The “International Convention against the Recruitment, Use, Financing and Training of Mercenaries,” adopted on 4 December 1989 and entering into force in 2001, prohibited the use of mercenaries under international law. Nevertheless, distinct from mercenaries, states have increasingly relied on commercial entities providing military and security services. In cases where states utilize PMSCs in military operations conducted on their behalf, they determine the legal relationship with such personnel. For instance, during the Ukraine–Russia war, the Russian government operated alongside a private military and security company known as the Wagner Group; however, following disputes with its leader, the matter was characterized as an issue of domestic law. Similarly, Israel has reportedly relied on private military and security companies alongside its national armed forces in operations in Palestine, and although the responsibility of such personnel remains debated in doctrine, their status has largely paralleled that of national military personnel.
However, the participation of such personnel in UN peacekeeping operations has led to the emergence of PMSCs as a new actor in international law, raising questions regarding accountability, particularly in relation to violations of human rights and international humanitarian law. This challenge arises because PMSCs operate primarily within a sphere driven by economic profit and are generally governed by private law contracts, whereas the protection of international peace and security constitutes a matter of international public law. The involvement of this new actor blurs the traditional distinctions within international law and creates uncertainty regarding applicable rules and enforcement mechanisms.
The legal issues posed by PMSCs have been acknowledged internationally. On 17 September 2008, Switzerland and the International Committee of the Red Cross introduced the Montreux Document, followed in 2010 by the “International Code of Conduct for Private Security Service Providers.” However, these instruments are considered soft law and are therefore not legally binding upon states. As a result, they do not impose enforceable international legal responsibility upon these actors. This raises the question of how such normative gaps may be addressed under international law.
Traditionally, states—and other legal persons—constitute the primary actors of international law. Accordingly, it may be argued that both the states hiring such companies and the private security companies themselves, as legal entities, could bear international legal responsibility for the acts of their personnel. However, personnel of PMSCs should also be subject to individual accountability, particularly criminal responsibility, for violations of international humanitarian law committed independently of states. Under international criminal law, individuals bear personal criminal responsibility for serious violations of international humanitarian law and may be prosecuted before the International Criminal Court (ICC), established on 1 July 2002 under the Rome Statute. In this context, it may be argued that PMSC personnel participating in UN peacekeeping operations could be held criminally liable for human rights violations they commit.
Nevertheless, international criminal law addresses only genocide, crimes against humanity, war crimes, and the crime of aggression. In the context of UN peacekeeping operations, personnel could primarily incur liability for war crimes, which significantly limits the scope of criminal accountability. Moreover, pursuant to Article 16 of the Rome Statute, the UN Security Council possesses the authority to defer ICC investigations or prosecutions, raising concerns that individuals tasked with ensuring peace and security might evade criminal responsibility.
Accordingly, the use of PMSCs as personnel in UN peacekeeping operations challenges the traditional framework of international law. Given their increasing prominence in contemporary practice, it is essential that their responsibilities be clearly defined through binding international legal instruments applicable to states.
Keywords: United Nations, UN Peacekeeping, Private Military and Security
Companies, Responsibility, International Law