Previous posts on Syria (see for example here and here) have commented on the air strikes by the US-led coalition, but the Russian air strikes on Syrian territory (as reported here and here) have been largely left undiscussed. This post will analyse the legality of Russia’s actions. Russia has been acting upon the request of President Assad (see here and here), which means that the international legal basis for Russia’s use of force is intervention by invitation. First, the concept of intervention by invitation itself needs to be addressed. Second, it is contested whether an intervention is even allowed during a civil war.
Intervention by Invitation
There is no explicit reference to intervention by invitation in the UN Charter nor is it covered by article 2(4). Pursuant to that article, states shall refrain from using force “in their international relations”. Using force upon an invitation, however, is not using force in international relations as no force is used by one state against another, but the two states are working together, using the force on one side. This falls outside the scope of article 2(4). Therefore no prohibition comes into play and this type of force is allowed. The importance of valid consent (the invitation) was addressed by the ICJ in the case DRC v. Uganda. The Court dealt with the situation after the consent had been withdrawn by the DRC, thereby emphasising the importance of valid consent, yet also indirectly making clear that before the withdrawal no violation of international law occurred. Thus, intervention by invitation falls outside the scope of article 2(4), as long as the consent is valid.
Intervention in a Civil War?
The second issue, which is a contemporary topic of international law as evidenced here, questions the legality of an intervention by invitation in a civil war. As Gregory H. Fox has indicated “‘civil war’ is not a critical term of art in international instruments” and it is therefore subject to different interpretations. The one followed here is from the 1975 Resolution and 2011 Resolution of the Institut de Droit International, which follow the definitions of non-international armed conflicts provided for in Common Article 3 and Additional Protocol II to the Geneva Conventions respectively. The threshold of a civil war is not met when “situations of internal disturbances and tensions, such as riots […], as not being armed conflicts” are involved. As the situation in Syria clearly goes beyond mere disturbances, it is hereby classified as a civil war.
Concluding that it is a civil war entails that there are two or more parties fighting for power. It could therefore be questioned who is entitled to issue an invitation for an intervention in Syria. It is argued here that Assad is still the correct issuing authority. First, in these situations there is a presumption of legitimacy towards the government as opposed to the opposition (see paragraph 246 of the Nicaragua judgement and e.g. De Wet). Second, while some states have ‘recognised’ the main opposition group, the Syrian National Coalition, they have only done so as “the legitimate representative of the people” (see also here and see here for a discussion on ‘recognition’ of the NTC in Libya). This ‘recognition’ was merely meant as political support for the Syrian people, not as legal recognition of a particular legitimate authority.
The subsequent issue to address is whether there is a rule that prohibits an intervention in a civil war. Two previous posts, one by Dapo Akande and Zachary Vermeer and the other by Raphael Van Steenberghe have already addressed the possible existence of such a rule. Both posts refer to governmental statements that justify the recent air strikes in Iraq against IS as evidence of state practice and opinio juris, but they reach opposite conclusions. It seems that an analysis of these two elements of customary international law is inconclusive. The reasoning of the ICJ might be of assistance.
The view that there is no prohibition to intervene during a civil war (as concluded by Akande and Vermeer) seems to be supported by the Court. In paragraphs 206 and 246 of Nicaragua, whilst not expressly referring to civil war, an intervention upon request of the opposition is said to be prohibited, while it is allowed on the side of the government. In paragraph 165 of DRC v. Uganda, the Court states that an interference in a civil war had occurred. However, in paragraphs 42-54 where the Court discusses consent, it rules that Uganda overstepped the boundaries of the consent given and that the consent was withdrawn at a certain point in time. The Court therefore seems to accept an intervention in a civil war when the consent is still valid. Combining the reasoning in these cases, it is concluded here that there is no such rule that prohibits an intervention during a civil war as long as the invitation comes from the government. Nevertheless, it must be noted that these cases were decided several years ago and the exception of fighting terrorism (as argued by Van Steenberghe and also here) could be a recent development. For this to be an exception to a rule, however, there must first exist a rule, which the Court does not seem to accept. In conclusion, there is no rule that prohibits an intervention by invitation in a civil war if the invitation comes from the government.
This conclusion is supported by the responses of other states to recent interventions by invitation. Fox (see above) has concluded that with the French intervention in Mali, no state argued that it was illegal, not for reason of there being a civil war nor for other reasons. Responses to the Russian intervention in Syria were numerous. A joint statement by several governments and a statement by NATO expressed deep concern about the intervention. Their concern, however, was directed to the fact that Russia was not exclusively attacking IS, but also the Syrian opposition. President Obama described the actions as leading to a quagmire. Yet no state disputed intervention by invitation as a valid legal basis for the intervention in this particular situation.
Russia’s intervention in Syria is in accordance with the concept of intervention by invitation and President Assad is still the legitimate authority to issue such an invitation on behalf of Syria. State practice and opinio juris are inconclusive and scholars are divided on whether there is a rule that prohibits an intervention in a civil war. On the basis of the reasoning of the Court and the responses of states to the recent interventions in Mali by France and in Syria by Russia, it is argued here that there is no such rule that prohibits an intervention in a civil war if the invitation comes from the government. It is thus submitted that the Russian intervention in Syria is in accordance with international law.