As the United States moves toward more open support of the Syrian rebels, several simmering international legal questions will likely become more prominent. Below is a thumbnail sketch of a few issues.
The legality of arming the rebels: Most obvious is the question of what international law says about arming rebels groups and how the United States will seek to justify the policy. Unsurprisingly, the Syrian government has described the policy as "incitement to murder." Russia, China, and others have also argued that the policy would be illegal. Vladimir Putin recently drew a sharp contrast between the legal basis for arming the government and that for supporting the rebels:
[L]et me draw your attention to the fact that Russia supplies arms to the legitimate government of Syria in full compliance with the norms of international law. We are not breaching any rules and norms. Let me emphasize that: we are not breaching any rules and norms, and we call on all our partners to act in the same fashion.
There's plenty of dissent within the West as well about the legal basis for arming the rebels. The Austrian government reportedly circulated a paper pointing out the legal problems with the policy. The argument against legality is straightforward: the Assad regime remains the recognized Syrian government, and the U.N. Charter does not permit other states to act against it militarily (other than in self-defense or with U.N. approval). There's plenty of legal support for the notion that providing arms (rather than, say, funds) to rebel groups itself constitutes a use of force, including the 1986 International Court of Justice ruling in the Nicaragua case.
But international law is murky on the issue, and there's ample room for the United States to argue that arming the rebels is lawful. Traditional international law supports the idea that outsiders can arm rebel movements that are widespread, well established, and that control territory. (Some ambitious international lawyers might even argue that there's an obligation to do so when the rebel movement faces the prospect of genocide or crimes against humanity.) As the Syrian rebellion solidifies, so does the legal basis for providing weapons.
A distinct legal question is whether sending arms to forces that might use them to commit human rights violations is illegal. There's no shortage of evidence that rebels have committed atrocities. The U.N. General Assembly recently approved an Arms Trade Treaty (ATT) that for the first time obliges states to take into account human rights law when it transfers weapons internationally. Many states are already parties to "codes of conduct" that emphasize the same principle. But the ATT ultimately allows each state to determine whether a weapons transfer threatens violations of the law, and there's no mechanism for reviewing that judgment. (What's more, the ATT likely won't come into force for at least a year.)
The legality of a no-fly zone: Recent reporting suggests that the United States is at least mulling the idea of a limited no-fly zone in Syrian airspace. The immediate legal question that arises is whether that kind of initiative would require a UN Security Council resolution. Most international lawyers argue that any coercive restrictions on a state's territory not in immediate self-defense require UN approval. Russian officials have made clear that they would veto any resolution authorizing a no-fly zone.
"All these maneuvers about no-fly zones and humanitarian corridors are a direct consequence of a lack of respect for
international law," a Russian official told Reuters.
Last week's Wall Street Journal account of U.S. thinking suggested that U.S. officials believe they can do so without UN approval.
Proponents of the proposal say a no-fly zone could be imposed without a U.N. Security Council resolution, since the U.S. would not regularly enter Syrian airspace and wouldn't hold Syrian territory.
U.S. planes have air-to-air missiles that could destroy Syrian planes from long ranges. But officials said that aircraft may be required to enter Syrian air space if threatened by advancing Syrian planes. Such an incursion by the U.S., if it were to happen, could be justified as self-defense, officials say.
That reasoning is a stretch, but there's a long history of Western legal gymnastics in this arena. NATO intervened in Kosovo without U.N. permission, and the United States and the United Kingdom patched together a legal rationale for the 2003 Iraq war. The key issue will not be the strength of the legal case but the strength of the political opposition to the move. Russia will squawk no matter what, but they'll also quietly let the West know whether a no-fly zone is something they can tolerate.
International prosecutions: The most obvious mechanism for holding accountable those committing abuses in Syria is the International Criminal Court (ICC). Because Syria is not a court member, however, the ICC will only acquire jurisdiction if the Security Council refers the case (the only other route would be if the national of an ICC member state committed crimes in Syria). A council referral appears impossible at the moment because of Russian and Chinese opposition. Even were Moscow and Beijing willing to acquiesce, it's not clear that Washington would support a referral, which might limit options for negotiating an Assad exit.
For the moment then, the courtroom door is barred. But that doesn't mean international justice won't play a role. If the rebel movement can solidify itself and win international recognition as the new government, for example, it could in theory give the court jurisdiction to investigate. The Rome Statute allows states -- even nonmembers -- to give the court the jurisdiction it needs by special agreement. For the rebels, the question would then be whether they're willing to accept the scrutiny that an ICC investigation would entail.