I’d like to offer a small “think piece” contribution to a bigger debate, in which I try and tease out a question that has troubled me: do we need a positive right of humanitarian intervention? What would happen if we conceded it was prima facie an unlawful use of force, but was legally (not just morally) justifiable or excusable in a particular case? My tentative conclusion is that the defence of necessity might prima facie be available to justify a use of force in an humanitarian intervention but would face some significant problems on close scrutiny.
We’re all by now familiar with a certain account of the development of the idea of humanitarian intervention. Let me offer a stylised version of this narrative, with its inevitable oversimplifications by way of introduction.
On one account humanitarian intervention begins as an idea supported by academics, is then invoked (not always consistently) by a small handful of States in concrete cases from the 1990s onwards, is opposed by the 170 member States of the Group of 77 and has now been at least partially supplanted by the “responsibility to protect” (R2P). Paragraph 139 of the World Summit Outcomes Document, however, would appear to reduce R2P to an agreement that the UN is the only legitimate forum for authorising intervention and that the Security Council should act in cases of humanitarian catastrophe. There is very little sign, though, of UN practice in support of this vision of R2P as a collective, institutional responsibility. On this stylised account, what began as an attempt to modify the positive rules on the use of force and non-intervention appears to have been folded back in to the status quo ante. (Albeit that a caveat might have to be entered regarding interventions endorsed or carried out by regional organisations.)
What has always puzzled me about the debate over forceful humanitarian intervention is that proponents and critics have invariably cast it being either a right or a duty. Are there any obstacles to conceptualising it as a justification or excuse for an otherwise illegal use of force? After all, the “right” of self-defence is easily considered such a “circumstance precluding wrongfulness” (i.e. a defence), and is categorised as such in the ILC Articles on State Responsibility.
Necessity may be invoked where the act which is otherwise contrary to an international obligation “is the only way for the State to safeguard an essential interest against a grave and imminent peril” (Article 25(1), ILC Articles). A State may plead necessity even where its own interests are not directly threatened; the ILC commentary to Article 25 refers to “a grave danger either to the essential interests of the State or of the international community as a whole”.
It would thus seem possible to plead the necessity of forceful intervention to suppress or prevent violations of obligations erga omnes, including at a minimum genocide and certain grave human rights violations (as in Barcelona Traction, para 34). Limitations circumscribing the defence’s availability are not hard to find. As the ILC Commentary to Article 25 notes (at para 5), the Caroline incident criteria provide a useful test of necessity: circumstances justifying necessity must be “instant, overwhelming, leaving no choice of means, and no moment for deliberation”. Vaughan Lowe has, elsewhere, helpfully suggested that forceful action cannot be necessary before diplomacy has been exhausted.
It strikes me that this approach to humanitarian intervention has one major advantage and a number of significant problems. The advantage is that if humanitarian intervention can be justified by a defence available at general international law, in principle there is no need for proponents to point to prior State practice substantiating a prior right of intervention. The lesser of my two problems is that this would involve a concession that any such intervention was prima facie illegal, which intervening States would likely find politically unpalatable. The more significant problem is the possible argument that “the international obligation in question excludes the possibility of invoking necessity” (Article 25(2), ILC Articles). That is, one may point to statements in the Definition of Aggression and the Friendly Relations Declaration to the effect that no consideration of any kind whatever may justify forceful intervention in another State.
Addressing this objection leads us back to the scope of the underlying prohibition on the use of force, and the old and unproductive debates about the correct interpretation of Article 2(4) of the UN Charter or the search for convincing State practice supporting humanitarian intervention outside institutional arrangements. On any objective head-count of UN members, it is quite clear the majority favour an absolute prohibition on intervention (absent UN authorisation, or perhaps action within regional arrangements).
Nonetheless, my argument might suggest that those States already publicly endorsing anticipatory self-defence based on the Caroline criteria could, completely consistently with this position, invoke a plea of necessity as an alternative justification for humanitarian intervention. This conclusion doesn’t perhaps advance debate a great deal, but I would be grateful to know if anyone has explored this line of thought in more detail.