Arming the Libyan rebels: tempting but illegal

As the military fortunes of the Libyan rebels wax and wane daily, there are increased calls for NATO and its allies to do more to help overthrow Muammar Gaddafi. This follows strong indications that CIA operatives and British special forces – several of whom were captured and briefly detained a few weeks ago – are already on the ground and aiding the rebels. But there has been a notable lack of commentary on the legality of these activities. Put bluntly, they are almost certainly illegal in international law.

In situations that threaten international peace and security, the Security Council has power under the UN Charter to authorise action by member states that would otherwise be subject to two key international law prohibitions: on intervention in the internal affairs of another state, and on the use of force.

International law has longstanding and tolerably clear rules on foreign intervention in internal conflicts. A state may, if invited, assist the government of another state to suppress a minor rebellion or domestic unrest. But if the internal conflict develops into a civil war – where, for example, the rebellion is on a large scale or the outcome uncertain – then any foreign intervention, invited or not, is forbidden. International law views civil war as an internal matter: it is for the people of each state to determine their own political fate, and other states cannot interfere in that process. The only exception to this prohibition is that a government facing civil war can still invite outside assistance where the rebels have themselves received foreign help.

So far as intervention to assist the opposition is concerned, this is, and always has been, illegal in international law. The theoretical basis for this has been debated over the years but the generally recognised rationales for the prohibition are the principle of non-intervention and respect for state sovereignty. As the International Court of Justice (ICJ) has made clear on more than one occasion, the principle of non-intervention prohibits a state "to intervene, directly or indirectly, with or without armed force, in support of an internal opposition in another State".

The merits or otherwise of the rebels' cause is immaterial: whether they are fighting to depose a brutal tyrant or a model democratic régime, no state may legally assist them. The United States would be particularly aware of this from their experience with funding and arming the contras in Nicaragua in the 1980s. In a case brought against the United States by Nicaragua complaining of these activities, the ICJ considered whether the US's assistance to the contras, in their attempts to overthrow the left-wing Sandinista government, could be justified on ideological grounds. The Court firmly rejected this, declaring that there was no exception in international law allowing intervention in support of an opposition whose political or moral values seemed particularly worthy.

This fundamental rule is not altered in Libya's case by the resolutions passed by the Security Council. Resolution 1973, authorising the no-fly zone, allows member states to take "all necessary measures" (Security Council code for the use of armed force) to protect civilians and – provided they have notified the Secretaries-General of the UN and the Arab League – to enforce the no-fly zone. All flights are banned except those to protect civilians or enforce the no-fly zone, and those for purely humanitarian purposes. Another, curiously worded, exemption is flights deemed "necessary … for the benefit of the Libyan people". No explanation of what is meant by this appears in the resolution or the official record of the Security Council's meeting. No doubt this was one the many "unanswered questions" of which Russia and China complained when abstaining from the vote on the resolution.

Even at its most expansive interpretation, however, nothing in the resolution authorises arming or actively assisting the rebels. Indeed, it strengthens the blanket arms embargo imposed on Libya in February, from which any exception must be approved by a committee of the Security Council comprising all its members. Thus any permission to provide arms or other materiél to the rebels would have to be obtained from, among others, Russia and China.

We hear that the Gaddafi régime has "lost legitimacy", but régime change has never been accepted as legalising unilateral intervention. Unless and until the rebels' National Transitional Council is recognised as the government of Libya – as France, Italy and Qatar have done – it remains, for the other 189 members of the United Nations, the opposition.

It is obvious that any use of force to protect civilians, because it is necessarily directed at the government, will be of direct benefit to the rebels. But blurred though it may appear in practice, there is a critical distinction between deterring attacks on civilians (and hence in some cases the rebels), and actively assisting the rebels to achieve their object of overthrowing the government.

Resolution 1973 has rightly been described as historic. It is the first and best example of the emerging doctrine of "the responsibility to protect": if a state is failing in its own responsibility to protect its population – which the Libyan government is clearly doing in using excessive force to suppress the rebellion – then the international community must exercise its responsibility to protect that population. This is exactly what coalition forces, acting pursuant to resolution 1973, are now doing, in contrast to the disputed legality of the NATO bombing of Kosovo in 1999. That campaign was seen by many as legitimate (morally right), but not legal.

Interested states have covertly, and sometimes overtly, assisted opposition groups in other states since time immemorial and it would be naïve to expect that to change. But recent comments do not seem to notice the clear legal prohibition of such assistance. It would be regrettable if the renewed respect for international law evident in resolution 1973 were to be simultaneously undermined by a flagrant violation of that law, however tempting it may be.