Regulating Military Force Series – Justice and Accountability in the Era of Modern Mercenarism

by | Feb 26, 2024


Editors’ note: The author delivered remarks on the subject of this post at the conference “International Law and the Regulation of Resort to Force: Exhaustion, Destruction, Rebirth?” at the Centre for International Humanitarian and Operational Law, Palacký University in Olomouc, Czech Republic.

The twenty-first century has witnessed a visible trend and an inevitable proliferation of private military companies (PMC), entities that offer military skills and expertise in conflict-affected areas. The term PMC is often used interchangeably with references to private military and security companies (PMSC), defined by the UN Working Group on the use of mercenaries as any “corporate entity which provides on a compensatory basis military and/or security services by physical and/or legal entities.” This post will address how the emergence of PMCs obfuscates the legal distinction between PMCs and mercenaries, followed by their status under international humanitarian law (IHL). The focus will subsequently shift towards an analysis of individual criminal responsibility and State responsibility in order to identify ways to achieve justice and ensuring accountability in the era of corporate mercenaries.

Terminology and Legal Distinction

The two international conventions that deal with mercenaries apply in situations of international armed conflicts (IAC) and non-international armed conflicts (NIAC). The purpose of both is to eradicate mercenaries through the criminalisation of their activities. The first is the International Convention against the Recruitment, Use, Financing and Training of Mercenaries. The second is the Organisation of African Unity Convention for the Elimination of Mercenarism in Africa (the Mercenary Conventions). According to the Mercenary Conventions, mercenarism is a crime and individuals who satisfy the definition of a mercenary may be prosecuted.

The definition of mercenary under the Mercenary Conventions is similar to that under IHL, namely Article 47 of Additional Protocol I to the Geneva Conventions (AP I). The main differences between the Mercenary Conventions and AP I are that the latter categorisation is limited to IACs and that under IHL being a mercenary does not amount to a breach of the Geneva Conventions or its Protocols.

Article 47(2) of AP I stipulates six cumulative conditions that an individual must satisfy to be classified as a mercenary. This definition has been described as unattainable and will seldom apply to personnel belonging to PMCs. Nevertheless, the fundamental question remains whether the PMCs of today can constitute modern-day mercenaries, particularly when scrutinising the activities of the Russian Wagner Group.

Status of PMC Personnel

A number of questions with respect to mercenaries and PMCs arise concerning the fundamental distinction between combatants and civilians, particularly in relation to certain activities performed by PMC personnel, which may amount to direct participation in the hostilities.


PMC employees may qualify for combatant status if they are members of the armed forces of a party to the conflict pursuant to Article 4A(1) of the Third Geneva Convention (GC III) and Article 43(1) of AP I. Alternatively, they may qualify as combatants if they are members of militias or volunteer corps that form part of such armed forces and they fulfil the specific criteria under Article 4A(2) of GC III.

The main feature that lies at the core of Article 4A(1) GC III and Article 43(1) AP I is integration into the armed forces. It may be argued that PMC employees seldom qualify as combatants. Firstly, the purpose of privatisation is to outsource the tasks at issue so that they do not need to be performed by the State’s armed forces. Secondly, incorporation would require the State to formally include contractors within its armed forces, which is debatable in light of States regularly striving to maintain plausible deniability.

In so far as Article 4A(2) GC III is concerned, the question is whether PMC employees as a group can satisfy the four cumulative requirements. On balance, it would be unusual for PMCs to meet these criteria. However, with respect to the Wagner Group and other Russian PMCs, President Putin signed a decree on 25 August 2023, which encompasses an oath of allegiance to Russia that includes a promise to strictly follow the orders of Russian military commanders and senior leaders relating to any activities in Ukraine.

According to the International Committee of the Red Cross (ICRC) Commentary to GC III, for a group to belong to a party to a conflict, first, it must “fight on behalf of that Party.” Second, “that Party must accept both the fighting role of the group and the fact that the fighting is done on its behalf” (para. 1005). It appears that the Wagner Group satisfies these criteria on the basis that it has a “fighting function” and fights on behalf of the State, hence it may be argued that a “relationship of belonging” for the purposes of Article 4A(2) exists (ICRC Commentary to GC III, para. 1008). The sole factor that is in dispute is the fourth criterion, namely “conducting their operations in accordance with the laws and customs of war,” meaning both treaty and customary IHL.

It is conspicuous that the Wagner Group has committed serious human rights violations and its members have defied the aforementioned criterion, thus they would be automatically disqualified from falling under Article 4A(2). However, it is worth noting that “non-compliance by one member of the group would not disqualify all the members of the group” (ICRC Commentary to GC III para. 1026) Therefore, it is arguable that some PMC employees may be categorised as combatants.


The next argument is whether PMC employees are civilians. The main feature is that they are not members of the armed forces and their conduct divests them of protection from attack “for such time as they take a direct part in hostilities,” as per Article 51(3) of AP I. The terms “direct participation” and “hostilities” may raise further legal arguments. However, these fall outside the scope of this post.

The view that PMCs are civilians is derived from the ICRC as well as the Montreux Document. The Montreux Document has no binding legal force but was the first international document to reaffirm States’ international legal obligations regarding the activities of PMCs. Currently, 59 States endorse the Montreux Document and Article 26(b) stipulates that private contractors are civilians.

It is arguable that PMCs should not be categorised as civilians given that it would considerably compromise the protection of the civilian population as a whole. The same holds true in relation to the classification of mercenaries as civilians under Article 47 of AP I, which is incongruous.

The demarcation line between combatants and civilians has not always been transparent, and the emergence of PMCs appears to have led to a further erosion of this division. The reality is that IHL did not foresee the PMCs of today. Therefore, it is arguable that they could fall under either of these categories based on the notion that the nature of their activities is dynamic and fluctuant, especially considering the Wagner Group.


It is indeed enticing to qualify PMCs as mercenaries or combatants, as opposed to civilians. However, there are multiple difficulties with this due to the intricacies involved concerning the legal criteria relating to each category. The primary issue stems from the definition of mercenary under Article 47 of AP I.

On the whole, the above demonstrates that the status of PMCs is obscure and vague, but one way to understand them depends upon the nature of their activities and affiliation, which are capable of being compared and amalgamated with mercenary activities. In fact, mercenaries are individuals who primarily work for pecuniary gain, whilst PMCs can indeed collaborate with these individuals by way of recruitment, hence they are capable of being defined as corporate mercenaries.

It is notable that President Putin denied the legal existence of the Wagner Group. Notwithstanding this assertion, it is important to note that Russia permitted its establishment as well as its formation, and it was effectively described as a proxy organisation of the Russian State.

Nevertheless, it should be noted that the Russian Criminal Code prohibits the recruitment, use, financing and training of mercenaries, as per Article 359, which arguably also means that the establishment of PMCs is not allowed. However, it appears that in reality, State-run companies can establish private armed security forces by virtue of Article 71 of the Russian Constitution, which stipulates that the responsibility for security and defence lies with the State.

Individual Criminal Responsibility

The doctrine of command responsibility and the challenges involved in superior orders can be difficult to satisfy. In the Čelebići case, the Trial Chamber of the International Criminal Tribunal for the former Yugoslavia (ICTY) helpfully elaborated three elements that must be proved in order for an individual to incur superior responsibility for the crimes committed by their subordinates (see also Blaškić).

The question is whether a PMCs’ superiors can be held responsible. A definite answer is only attainable if PMCs have an internal organisation that would establish effective control of superiors over subordinates, which is indeed disputable. This is because generally, they do not fall under a standard hierarchy or chain of command overseen by the military or other security organs. Therefore, the process of proving the existence of a superior-subordinate relationship is more arduous. However, a de facto position of authority, as opposed to de jure, is of particular relevance.

A practical example is the case of torture in Abu Ghraib prison in 2004 where PMC employees tortured detainees alongside U.S. military personnel. Certainly, the employees from CACI International and Titan Corporation, involved in the inhumane interrogations, were holding a position of authority and command. It is worth noting that Major General Taguba asserted that although these private contractors were not supervising any military personnel, those involved in the mistreatment considered members of the PMSC to be the “competent authority.” Therefore, it is arguable that the PMSC employees in Abu Ghraib exerted effective control over the military perpetrators for the purposes of command responsibility.

In the case of the Wagner forces, according to the Institute for the Study of War, they “assisted other Russian troops in the Battle of Severodonetsk, serving as the main assault forces alongside Rosgvardia elements in late June 2022.” In July 2022, the Wagner Group deflected their attention to Bakhmut, effectively taking “the lead” in the subsequent offensive in August 2022. In relation to the operations in which Wagner assisted Russian troops, it is arguable that the military personnel may have exerted effective control over the members of Wagner who were under their command. On the other hand, in relation to the Bakhmut offensive, the Wagner forces were operating under their own command. Therefore, it appears that such command relationship mutates according to the facts of the particular situation.

Following Yevgeny Prigozhin’s demise, it was announced that his son Pavel Prigozhin has taken over “command” of the Wagner Group and that he has been negotiating with the Russian National Guard, known as Rosgvardia, in relation to rejoining combat operations in Ukraine. In fact, it has recently emerged that the Wagner Group is now part of this separate unit, namely Rosgvardia. This signifies that they are effectively incorporated into a militarised force which, albeit separate from the army, it is directly subordinate to President Putin. Furthermore, it has been reported that contracts have also been signed with different Russian PMCs under the command of the Ministry of Defence (MoD), such as Redut, which is under the direct supervision of the MoD. It is evident that Wagner’s independence ceased to exist in view of the fact that its former operatives are splintered into the MoD on one side and Rosgvardia on the other. It remains to be seen how the chain of command will crystallise in light of the above for the purposes of command responsibility. Nevertheless, it is indisputable that they are subordinate to President Putin and will continue to pursue Russia’s objectives in Ukraine and Africa.

Individual criminal responsibility is an available avenue for accountability, but it has a very limited applicability in practice due to the fact that PMCs pose significant challenges. Thus far, no private contractor has yet been prosecuted for committing war crimes and crimes against humanity. There is indeed a clear accountability gap, which ought to be addressed. The principle of universal jurisdiction is of particular importance, based on the concept that the fight against impunity is in fact borderless.

State Responsibility

The ILC Articles on State Responsibility reflect customary international law and have been recognised in international judgments. One of the possible attribution criteria that may be used in order to hold States accountable for violations of the jus ad bellum under the ILC Articles is if the PMC is acting “on the instructions of, or under the direction or control of, that State in carrying out the conduct,” under Article 8.

It is worth drawing the attention towards two international courts, which have provided different interpretations of the direction and control exercised on behalf of the State. The International Court of Justice (ICJ) adopted a strong test of attribution for acts of individuals to States in the Nicaragua case, namely the “effective control” test.

The ICJ, having denied the equation of the contras with an organ of the State, had to determine whether the actions of the contras or “mercenary forces” encompassing torture, rape, kidnapping, assassination, killing of prisoners and civilians, could be attributed to the United States. At paragraph 115, the Court asserted that the participation by the United States in the “financing, organizing, training, supplying and equipping of the contras, the selection of its military or paramilitary targets, and the planning of the whole of its operation” was not sufficient to lead to attribution, on the basis that such acts could have been committed without the control of the State. The ICJ made it plain that what must be proved is that the United States had effective control over the contras’ actions in breach of IHL. More specifically, the available evidence must indicate that the United States “directed or enforced” the above acts perpetrated by the contras contrary to human rights and humanitarian law.

In addressing conflict classification for the purposes of IHL applicability, the ICTY adopted the “overall control” test in the case of Tadić. The Appeals Chamber held that the crimes committed by the Bosnian Serbs in Bosnia and Herzegovina could be attributed to the Federal Republic of Yugoslavia (FRY), given that the FRY exercised “overall control” over the Bosnian Serbs. The ICTY’s judgment differed from that of the ICJ, thereby concluding that there was no requirement to prove that each individual operation was carried out under the FRY’s specific instructions or under its effective control, according to paragraphs 129 and 131. The control required, as per paragraph 137, “may be deemed to exist when a State . . . has a role in organising, coordinating or planning the military actions of the military group, in addition to financing, training and equipping or providing operational support to that group.” Furthermore, the actions of the group may be considered as “acts of de facto State organs regardless of any specific instruction by the controlling State concerning the commission of each of those acts.”

Considering Tadić, it is arguable that the “overall control” test better reflects the realities of the upsurge in PMCs who may be under sufficient influence and control by a State. Although this test might have its drawbacks due to the fact that it would arguably expand the scope of State responsibility, a possible way to hold Russia accountable would be to exercise the “overall control” test on the basis that the Wagner Group can indeed be considered as under its sufficient influence and control.

President Putin admitted to financing Wagner and it is clear that the group relied on the Russian State for military equipment and logistical support. However, as previously indicated, this is insufficient for the test of “effective control” to apply. This is a situation that can be compared with Serbia financing the Serbian paramilitary units. During the 1991-1999 wars in Croatia, Bosnia and Kosovo, these paramilitary units committed, inter alia, war crimes and genocide. They performed such acts under a veneer of dissociation from the Milošević regime, thereby rendering it possible for State officials to assert that the Serbian paramilitaries were acting independently.

The main issue with the “effective control” test pertains to evidence that a particular group has acted upon the instructions, or direction, or under the specific control of a State in relation to each individual operation. Therefore, the clear evidentiary problems can be remediated by applying the “overall control” test as a means to attribute responsibility to Russia for the gross human rights violations perpetrated by the Wagner Group in order to achieve justice and accountability.


At present, there is no clear definition of PMCs, whether they can be defined as mercenaries, combatants or civilians under IHL, and accountability is clearly non-existent.

Several States have been deploying PMCs to influence conflicts in a surreptitious way to prevent any identifiable nexus between corporations and States. In fact, there is often a lack of evidence to corroborate any such link, consequently allowing States to resort to plausible deniability, which presents considerable challenges in terms of the ability to attribute human rights breaches as well as to be able to provide remedies to victims of such violations.

Today, mercenaries give the impression of being disguised as PMCs in order to make them appear legitimate, leading to what can be defined as modern mercenarism. In other words, PMCs appear to be the modern metempsychosis of mercenaries concealed under the cloak of legitimate corporations. The reality is that these corporate mercenaries are the future of warfare and they will only perpetuate conflicts around the world, thereby posing a powerful threat not only to human rights, but also to international peace and security.


Clarissa Rodio is a Barrister at Great James Street Chambers, London.



Photo credit: BelTA News Agency