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The legal basis for foreign military intervention in Syria

Do Russia and the US-led coalition have the right to be militarily involved in the Syrian civil war under international law?

According to a statement from the Independent Doctors Association (IDA), on 23 July 2016, the regime of Syrian President Bashar al-Assad, backed by the Russian Air Force, launched air strikes against five medical facilities in opposition-controlled areas in eastern Aleppo: four hospitals, including a paediatric hospital, and the Central Blood Bank which is the last remaining blood bank in operation in the city.

This attack was perpetrated a fortnight after pro-regime forces, with the support of the Russian Air Force, seized Castello Road – the only route to and from opposition-controlled neighbourhoods in eastern Aleppo, thus impeding the distribution of humanitarian aid to at least 200,000-300,000 people living in these neighbourhoods as well as their evacuation to safer areas. 

These events have raised several questions: first, is Russia’s military involvement in the Syrian civil war legal under international law?

In September 2015, following a request from his Syrian counterpart, Russian President Vladimir Putin received authorisation from the Federation Council (Russia’s upper house of parliament) to launch air strikes on Syrian soil, invoking the international legal principle of “intervention upon invitation”.

Two legal conditions must be met in order to invoke this principle: the validity of the invitation (valid consent) and the legitimacy of the inviting authority.

Arguably, the invitation of the Syrian regime is valid. However, is the regime of Bashar al-Assad the legitimate authority of the Syrian people?

Second, is Russia violating international humanitarian law?

The Russian Air Force is targeting opposition-controlled areas, including non-military targets such as hospitals. According to the most recent report from the Syrian Observatory for Human Rights (SOHR), since 30 September 2015 when Russia began its military engagement in the Syrian civil war, at least 7,210 people have been killed in Russian aerial attacks, including 2,600 Syrian citizens (non-combatants).

Isn't killing civilians a war crime?

Also, today, there is no United Nations Security Council (UNSC) resolution authorising the use of foreign military force on Syrian soil, nor regime consent for non-Russian air strikes on its territory; even non-Russian air strikes conducted against targets of the self-proclaimed Islamic State (IS).

Therefore, does the US-led coalition have a legal basis for military action in Syria in the absence of specific authorisation from the Security Council and/or Syrian consent?

Russia’s military engagement in Syria’s civil war

Article 2(4) of the UN Charter states that “all members [UN member states] shall 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”.

That is to say, the use of military force by one UN member state in or against another state is illegal under international law.

This rule, however, is subject to three exceptions: military action in self-defence, military action authorised by the Security Council under Chapter VII of the UN Charter, and military action based on the principle of “intervention upon invitation”.

This principle allows the following: a state might request other state or states to use military force within its territory invoking the international legal principle of intervention upon invitation, as the Iraqi government – considered the legitimate government of Iraq – did in 2014 when it requested the US to lead international military efforts against IS.

As stated above, two legal conditions must be met in order to invoke the principle of intervention upon invitation: the validity of the invitation (valid consent), and the legitimacy of the inviting authority.

While Russia has not yet issued an official document outlining the request of the Syrian regime, the valid consent of Syrian President Bashar al-Assad is observable: there is a coordination of military operations between pro-regime ground troops and Russia’s Air Force.

The question is: which entity – the Assad regime or the opposition – is the legitimate authority of the Syrian people? And thus, which entity can legitimately issue an invitation?

The International Court of Justice (ICJ) addressed a similar situation during the case of Nicaragua vs the United States, 1986: the plaintiff – Nicaragua – claimed that the US had violated the sovereignty of Nicaragua through a number of actions. In response, the US upheld that it was acting under the principle of intervention by invitation, following the receipt of an invitation issued by the Nicaraguan opposition.

The ICJ stated then that the invitation to intervene in the sovereign affairs of a foreign state only possesses legal basis if the invitation in question is extended by the legitimate government of the state, and not by the opposition.

Similarly, it could be argued - since no authority exists that can enforce, delineate, or interpret international law - that Russia’s military intervention in the Syrian civil war is legal, as the Syrian regime which is the legitimate government of Syria, according to Russia, did issue an invitation for Russian military intervention.

Following this line of thought, it can also be argued that the states invoking the excuse of counter-terrorism in order to be present on Syrian territory without the consent of the Syrian regime – whether on the country’s land, in its airspace or in its waters– are violating Syrian sovereignty.

Now, is Russia failing to comply with international humanitarian law (IHL)?

According to Article 20 of the text Responsibility of States for Internationally Wrongful Acts of the International Law Commission, the principle of intervention upon invitation can only stand as a legal basis if no actions taken by the invited state constitute a violation of pre-emptive norms of international law – otherwise, the principle is thereby nullified.

Several organisations, including Amnesty International and Human Rights Watch, have demonstrated that Russia’s actions in Syria – the launch of aerial strikes against hospitals, for example – constitute a violation of IHL.

Should Russia be proven to have committed violations of IHL, its pretence of defaulting to the principle of intervention by invitation would no longer have legal justification.

US-led military intervention in Syria’s civil war

Security Council resolution 2249 (2015), which was adopted unanimously by the UNSC on 20 November 2015, calls upon member states “to take all necessary measures, in compliance with international law, in particular with the United Nations Charter,” against IS and the former al-Qaeda-affiliated Jabhat al Nusra - now the Levantine Conquest Front - both groups on Syrian and Iraqi soil.

Contrary to common belief, resolution 2249 does not authorise member states to use military force against the aforementioned groups, as it does not refer to Chapter VII of the UN Charter.

In order to provide member states with legal authority for the use of military force against the groups in question, a Security Council resolution needs to constitute a decision taken under Chapter VII of the UN Charter, which presents members states with a “loophole” to the general prohibition of the use of force encompassed in Article 2 of the UN Charter.

Therefore, the US-led coalition is not authorised by any Security Council resolution to use military force in Syria.

The question, then, remains: in the absence of Syrian regime-consent and/or a specific authorisation from the Security Council, does the US-led coalition have a legal basis for military action in Syria?

Throughout 2014, the internationally recognised government of Iraq requested “the assistance of the international community” to fight IS, and provided “express consent” for US-led intervention in Iraq.

For instance, in September 2014, in a letter sent to the president of the Security Council, Iraq emphasised that: “In accordance with international law and the relevant bilateral and multilateral agreements, and with due regard for complete national sovereignty and the Constitution, we have requested the United States of America to lead international efforts to strike ISIL sites and military strongholds, with our express consent.”

Thus, the air strikes launched by the US-led coalition against IS in Iraq have taken place on the legal basis of “intervention upon invitation”. 

There is no “invitation” nor “express consent” from the Syrian regime for US-led coalition air strikes against IS in Syria, however. 

Consequently, the actions of the US-led coalition in Syria have been legally justified using Article 51 of the UN Charter: the US-led coalition is exercising individual self-defence, and collective self-defence.

If self-defence is invoked against a non-state armed group – IS, in this case – it must be shown that the state in which the armed group is found – Syria – is “unwilling or unable” to prevent it from attacking other states. Ostensibly, Syria is “unable” to sufficiently degrade or destroy IS because the group controls a significant amount of territory within Syria’s borders that pro-regime forces have not been able to reclaim.

It can be argued, then, that acting in individual self-defence is permissible because the Syrian regime is “unable” to prevent IS from launching attacks against states, including the US, the United Kingdom and France.

Furthermore, it can be argued that acting in collective self-defence – on behalf of Iraq – is permissible because the Syrian regime is “unable” to prevent IS from attacking Iraq from Syrian territory.

Humanitarian intervention

As it did in 2011 against the Libyan regime of Muammar Gaddafi, the Security Council can authorise military intervention in Syria for humanitarian purposes provided that it has determined that there is a threat to international peace and security.

Why has the Security Council failed to do so against the Syrian regime? Whatever the reasons, the humanitarian dimension has been marginalised in Syria.

- Tania Ildefonso Ocampos is a Spanish political analyst who specialises in EU strategy in the Middle East. She is a former Schuman trainee (Euro-Med and Middle East Unit of the European Parliament's Directorate-General for External Policies), and holds an MA in Middle Eastern History from Tel Aviv University, Israel.

The views expressed in this article belong to the author and do not necessarily reflect the editorial policy of Middle East Eye.

Photo: an image taken from footage made available on the Russian Defence Ministry's official website on 5 October 2016, purporting to show Russia's Su-24M bomber dropping bombs during an air strike in Syria (AFP/Russian Defence Ministry).  

This article is available in French on Middle East Eye French edition.

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