Mounting tensions between Russia and Ukraine, as well as the existing hostile situation in eastern Ukraine, has foregrounded, in addition to diplomacy and military might, the relevance and adequacy of the applicable international legal framework. The recent turn of events raises the question whether and to what extent the law of occupation applies to Russia’s actions in the Donbas/Donetsk and Luhansk People’s Republics. Put differently, is Russia militarily now occupying the Donbas/Donetsk and Luhansk regions through proxies? And are both Russia and the members of those local insurgent forces accordingly in violation of the Geneva Convention on Civilians – by engaging, for example, in the unlawful deportation and transfer of protected persons as well as compelling protected persons to serve in the forces of a hostile army? More generally, how does humanitarian law of international armed conflict apply in these regions and with it the obligation on all states to prosecute or extradite suspected war criminals?

First, a recap of some of the most recent events.

On Feb. 15, 2022, with reference to Ukraine’s eastern part, Russian President Vladimir Putin stated that: “In our view what is now happening in Donbas is genocide.” These claims are not substantiated and, indeed, are baseless. It is thanks in part to the clarity of international law that we know such claims do not come close to making the grade.

In parallel, Russia-backed separatists, in control of parts of Ukraine’s east, without providing credible evidence claimed that the Ukrainian military was on the verge of attacking, and ordered the evacuation of women, children and elderly to Russia’s Rostov region. Then, on Feb. 19, Russian-backed separatist leaders of Ukraine’s two breakaway regions announced a general mobilization, calling on their citizens to be militarily conscripted in view of repelling an allegedly forthcoming Ukrainian attack.

On Feb. 21, 2022, President Putin recognized Donetsk and Luhansk as independent states. He then ordered the Russian Defense ministry to deploy troops to the breakaway regions. The sending of Russian troops onto Ukrainian territory will itself trigger the law applicable to international armed conflict. But what about the law of occupation specifically – regardless of the deployment of such troops — and what legal responsibility may attach to individuals engaged in violations of that law?

Whether Russia had the status of occupant pursuant to international humanitarian law in the eastern part of Ukraine, as in Crimea, was not as easily ascertained prior to recent events. In fact, the armed conflict in the eastern part of Ukraine was regarded by many to be a Non-International Armed Conflict (NIAC), that is one between the Ukraine state government and the separatists, while a separate International Armed Conflict (IAC) took place between Russia and Ukraine. This is because the facts substantiating Russian state involvement in the actions of separatist groups appeared to be lacking; Russia training, equipping and providing the separatist parties with weapons did not on its own meet the required legal test of overall control (more on that text below).

Admittedly, those cautious assessments may have been based on insufficient understanding or knowledge of the underlying (clandestine) relationships between Moscow and the separatist groups. But the facts are now clearer and events have shifted to cross the legal threshold.

The first part of this essay thus examines the concept of “proxy occupation.” The second part asks whether Russia is a belligerent occupier in light of the legal framework, through a comparison of two competing tests (the effective and overall control tests). The grave breaches regime in times of military occupation is briefly touched upon in the third part. The conclusion I reach is that Russia and the local separatist authorities have to fully abide by the international humanitarian law of military occupation in this particular situation.

Military Occupation by Proxy

There is no conventional international humanitarian law notion that would define military occupation through proxy a.k.a. by intermediary. Hague Convention (IV) respecting the Laws and Customs of War (1907) in Article 42 conceives of a state acting through its armed forces directly. It thus contemplates a form of a classic military occupation:

“Territory is considered occupied when it is actually placed under the authority of the hostile army.
The occupation extends only to the territory where such authority has been established and can be exercised.”

While the same is presumed in Article 2 Common to the 1949 Geneva Conventions, the latter makes the conventions applicable “to all cases of partial or total occupation of the territory of a high contracting party even if the said occupation meets with no armed resistance.” Pursuant to this passage, military occupation can also come about without direct engagement of forces.

Yet because states act through armed groups in armed conflicts channeling their own interests, one should query whether a state can be seen as a military occupant even when it does not control the territory through its own armed forces (per Art. 4 of the Articles of State Responsibility), but instead through local de facto entities or an armed group (per Art. 8 Articles of State Responsibility).

While international law does not provide a direct and straightforward answer on how to deal with this phenomenon, there is an indirect and sufficiently clear approach. At play would be two thresholds of control. They have to operate together, in tandem: state X would need to exercise control over a de facto entity/an armed group (the proxy); and control over the territory as understood in Article 42 of the Hague Regulation of 1907 for the purposes of establishing military occupation needs to be exercised by that intermediary. The threshold of control in Article 42 is that of effective control. What is debatable is the threshold for the control that has to be exercised by the state over the proxy: should it be effective or overall? Some side with the application of the effective control test (E. Benvenisti, The International Law of Occupation (OUP, 2013) at 62; Y. Dinstein, The International Law of Belligerent Occupation (CUP 2019) at 50).

Thus, the tension between the complete dependency, effective control and overall control tests comes forth. The first two belong to the International Court of Justice (ICJ) dicta (in Nicaragua) and are stringent in their application. The last test belongs to the International Committee of the Red Cross (§§ 271-273) and the International Criminal Tribunal for the Former Yugoslavia (ICTY) (Tadic judgment) and is less stringent in its criteria and comparably easier to be met.

These control thresholds also beg the question whether there should be one test for establishing state responsibility and for determining whether an international armed conflict exists due to a state’s relationship to an organized armed group. Establishing state responsibility and state participation in armed conflict, in the view of this writer, denotes the same thing, hence, in my view would necessitate one and the same test.

Irrespective of the above posed question, in terms of the law of state responsibility, the test of complete dependency occurs when state responsibility is engaged for the actions of its de jure or de facto organs through exercising total control over their actions (Nicaragua v. United States of America, ICJ Judgment 1986, §§ 86-110; Bosnia and Herzegovina v. Serbia and Montenegro, ICJ Judgment 2007, §§ 386-393). The test of effective control is couched in Article 8 of the Articles of State Responsibility, where the state responsibility is triggered for the actions of persons or group of persons who are acting on the instructions, or under the direction and control, of the state in question (Nicaragua v. United States of America, ICJ Judgment 1986, § 115; Bosnia and Herzegovina v. Serbia and Montenegro, ICJ Judgment 2007, §§ 396-397, § 400, §§ 405-406). This level of control is lower than the complete dependency one.

As regards the overall control test, the ICTY discussed this threshold, and it too may be grounded in Article 8 of the Articles of State Responsibility. The ICTY did not follow the footsteps of the International Court of Justice in upholding the effective control test interpretation, determining state responsibility for de facto organs (armed groups and de facto authorities). It went further and offered overall control to be suitable for establishing both state responsibility for the actions of the armed group and determining whether an international armed conflict exists (Tadić, ICTY Appeals Chamber 1999, §§ 115-131):

“[T]he State wields overall control over the group, not only by equipping and financing the group, but also by coordinating or helping in the general planning of its military activity … it is not necessary that, in addition, the State should also issue, either to the head or to members of the group, instructions for the commission of specific acts contrary to international law.” (Tadić, ibid.§ 131)

The ICJ did not agree with the ICTY on using the overall control test for establishing state responsibility. According to the ICJ, the ICTY in general was not called upon to opine on the issue of state responsibility, because the ICJ’s jurisdiction was limited to criminal matters extending to persons. (Bosnia and Herzegovina v Serbia and Montenegro, Merits, Judgment, ICJ, 2007 (Genocide case) § 403). However, and important to our analysis, the ICJ went out of its way to accommodate the overall control test: to ascertain whether the armed conflict was of an international character, the overall control test could be “applicable and suitable,” according to the ICJ (ibid. § 404).

This line of thought is also consistent with the ICRC Commentaries of 2020 to Geneva Convention III which directly addressed the legal question at hand. The ICRC states (in a section titled, “Occupation by Proxy”):

“Under humanitarian law, effective control over all or parts of a foreign territory may be exercised through surrogate armed forces as long as they are subject to the overall control of the foreign State. Thus, a State could be considered as an Occupying Power when it exercises overall control over de facto local authorities or other local organized groups that are themselves in effective control of all or part of a territory” (§ 363).

And it should be understood that the ICTY in Tadic and subsequently also applied the overall control test specifically to the situation of occupation by proxy (Prosecutor v. Tadić, Trial Chamber, Judgment, 1997 § 584 (“the relationship of de facto organs or agents to the foreign Power includes those circumstances in which the foreign Power ‘occupies’ or operates in certain territory solely through the acts of local de facto organs or agents”); Prosecutor v. Blaškić, Trial Chamber, Judgment, 2000, § 149 (“Croatia played the role of occupying Power through the overall control it exercised over the HVO”); Prosecutor v. Prlić, Appeal Judgment, Case No. IT-95-14-T, 2017, § 325 & 334).

This application of the overall control test for conflict classification purposes in international humanitarian law is consistent as well with the International Criminal Court’s jurisprudence (see, e.g., Prosecutor v. Lubanga, ICC Trial Judgment, 2012, § 541-542 (applying overall control test in context of military occupation); Prosecutor v. Lubanga, ICC Pre-Trial Chamber, Decision on Confirmation of Charges, 2007, § 211 (“where a State does not intervene directly on the territory of another State through its own troops, the overall control test will be used to determine whether armed forces are acting on behalf of the first State. The test will be met where the first State has a role in organising, co-ordinating or planning the military actions of the military group, in addition to financing, training and equipping the group or providing operational support to it.”); Prosecutor v. Bemba, ICC Trial Judgment, 2016, § 130).

In sum, the overall control threshold seems to be the most relevant in establishing whether the situation involves an international armed conflict especially and including belligerent occupation. Such a situation would also mean that the grave breaches regime of the Geneva Conventions would be applicable.

In concluding this analysis, one important aspect should be emphasized concerning establishing the overall control threshold. If proven that a territorial adjacent state has territorial aspirations, that is trying to enlarge its territories via the armed group, it may be relatively easier to prove the overall control threshold. The ICTY stated:

“Where the controlling State in question is an adjacent State with territorial ambitions on the State where the conflict is taking place, and the controlling State is attempting to achieve its territorial enlargement through the armed forces which it controls, it may be easier to establish the threshold.” (emphasis added)

(Tadić, ICTY Appeals Chamber 1999, § 140). Obviously, proving territorial enlargement aspirations are vital in this regard. Should Russia annex the breakaway regions, like it did in the case of Crimea, it will beyond certainty be the case. But that extreme action is not necessary for the application of the ICTY’s analysis.

Applying Overall Control to Establish Proxy Occupation: The Russian case

The overall control test is valuable for establishing when proxy occupation exists. Proxy occupation then consists of three components: 1. the presence of a foreign state and an armed group/de facto authority, neither of which is the legitimate government of the territory in question; 2. the relationship between the two satisfies the overall control test (as developed by the ICTY, ICC, and ICRC); and 3. the armed group or de facto authorities effectively control the territory (or parts of it) as envisaged by Article 42 of the Hague Regulation and Common Article 2 of the Geneva Conventions. The combination of these elements would form the overall test that determines the existence of a proxy occupation. (N. Kalandairshvili-Mueller, Occupation and Control in International Humanitarian Law (Routledge, 2021) at 88).

In the case of Eastern Ukraine, and in light of the recent events, a strong argument can be made that the Donetsk and Luhansk de facto authorities’ actions are very much coordinated with the Russian government and are part of a wider military effort that Russia is carrying out both along the border of Ukraine and inside each breakaway region. The relationship between the Russian government and the separatists from Donetsk and Luhansk were not always easy. Initially, Moscow did not exhibit so much determination and support for the separatists’ cause, unlike in Crimea. It remained much more reserved in extending assistance to the separatists in the Eastern Ukraine and was not that eager to facilitate the creation of Novorossiya (International Crisis Group, Rebels Without the Cause: Russia’s Proxies in Eastern Ukraine (2019) at 8). Yet Moscow continued to help the separatists militarily, but on its own terms (ibid., at 9-10). Moscow, in the initial stage of the conflict, also struggled to control the de facto authorities, who were caught up in internal power struggles involving murders and rivalries. By spring 2019 Moscow solidified control over the Donetsk and Luhansk authorities. (ibid. at 11), after the Russian military had already deeply embedded themselves in the command and control of the military forces of those authorities (see International Crisis Group, Russia and the Separatists in Eastern Ukraine (2016) at 8; Vladimir Peshkov, The Donbas: Back in the USSR, European Council on Foreign Relations, 2016; Donald N. Jensen, Moscow in the Donbas: Command, Control, Crime and the Minsk Peace Process, NATO Defense College Research Report, 2017).

Official Kiev does not control the de facto authorities, hence also not the regions in question. In fact, Ukraine considers these territories to be “temporarily occupied territories” (see here and here). It is clear that Russia has now been stepping up in helping the general planning of military activities by the breakaway regions, unlike in previous years when Russia was not so actively supportive of the independence of the breakaway regions (International Crisis Group, ibid). Russia has, in sum, stepped up its involvement and assistance to the separatist regions, going beyond mere financial and weapons provisions, to also entail Russia’s coordinating or assisting the military activities of the de facto authorities in Donetsk and Luhansk. Separatist authorities in eastern Ukraine planning to evacuate their breakaway region’s residents into Russia and the Russian president ordering its government to provide refuge to civilians from Donetsk and Luhansk seem to further substantiate this assessment.

This relationship is also indicated by the de facto heads of the breakaway regions ordering the full mobilization of their troops and urging reservists to show up at military enlistment offices. Such orders suggest the breakaway regions de facto authorities to be assigned their military tasks and activities by Russia. The Declaration by the High Representative on behalf of the EU on the situation in eastern Ukraine and the Russian military build-up also stated the EU to be:

“extremely concerned that staged events, as noted recently, could be used as a pretext for possible military escalation. The EU is also witnessing an intensification of information manipulation efforts to support such objectives. … The EU sees no grounds for allegations coming from the non-governmental controlled areas of the Donetsk and Luhansk regions of a possible Ukrainian attack. The EU urges Russia to engage in meaningful dialogue, diplomacy, show restraint and de-escalate.”

This wording is suggestive that Russia is in general control of the armed conflict dynamic, including of the actions of the separatists, and that the latter are to be regarded pursuant to the above analysis as its proxies.

Grave Breaches Regime

The 1949 Geneva Conventions and AP I outline grave breaches, i.e., particularly serious violations that give rise to specific obligations of States to repress them. Instances of grave breaches must be criminally prosecuted by High Contracting Parties essentially on the basis of the principle of universal jurisdiction. Legally, however, this regime is found only during international armed conflict and for relevant violations of the law of occupation that rise to a grave breach. Therefore, in case Russia is actually militarily occupying Donbas and Luhansk through proxies, the separatists could be prosecuted for violating Article 147 of Geneva Convention IV (e.g., compelling protected persons to serve in the forces of a hostile power, unlawful deportation of protected persons). The separatists and Russia are also fully bound by the conduct of hostilities provisions enshrined in Additional Protocol I 1977, and all parties to the armed conflict should by all means observe them. The incident involving the shelling of a kindergarten from the separatist occupied area into the Ukrainian controlled territory is just one example of an apparent violation of the law.

Practically all states of the world are parties to the Geneva Conventions. They all have a legal responsibility to enforce the Conventions through the system of grave breaches.


Russia has to fully abide by the international humanitarian law of military occupation in this particular situation. More specifically, Geneva Convention IV should be applicable to the actions of the Russian backed separatists, along with other rules of international humanitarian law. All are also bound by the application of human rights law, applicable to all the warring parties.


I thank Professor Ryan Goodman for his very helpful suggestions and advice.

Photo credit: Standing before an emergency meeting of the UN Security Council in Monday night, Permanent Representative of the Russian Federation to the United Nations Vasily Nebenzya fist bumps Ambassador Zhang Jun, Permanent Representative of China to the UN, as US ambassador to the UN Linda Thomas-Greenfield and Permanent Representative of Norway to the United Nations Mona Juul look on. February 21, 2022 (Photo by Timothy A. Clary/AFP via Getty Images)