In the years since 9/11, drone strikes have emerged as a pillar of the United States’ counterterrorism strategy. The Cipher Brief spoke with Bobby Chesney, Professor of Law and Associate Dean of Academic Affairs at the University of Texas Law School about the legal basis for U.S. drone strikes abroad. According to Chesney, while the U.S. has asserted its right to use force against al Qaeda and its affiliates wherever they may be located, “that no-geographic-limits claim has drawn lots of criticism, especially overseas.”
The Cipher Brief: What is the legal justification that U.S. policymakers use for conducting drones strikes against terrorist targets abroad?
Bobby Chesney: As an initial matter, the U.S. government asserts authority to use force against a specific set of groups—most notably al Qaeda and the Islamic State—pursuant to an authorization for use of military force (AUMF) passed by Congress in 2001, shortly after 9/11. That statute authorizes force against whichever group the president determines is responsible for the attack (al Qaeda), and any entity harboring them (Afghan Taliban).
The government has long asserted that this also encompasses authority to use force against “associated forces” of those groups if they engage in hostilities against us (for example, AQAP in Yemen). That view has been endorsed in the detention context both by federal judges and by a subsequent statute.
However, this might leave readers wondering about the Islamic State, which once was al Qaeda in Iraq (AQI) but famously went independent. The administration’s theory is that, as al Qaeda in Iraq, the group certainly was covered by the 2001 AUMF, and they don’t get to exempt themselves from coverage simply by breaking ties with the senior leadership and changing their name, absent good reason to believe that the group also is no longer hostile to the United States. I do not expect President-elect Donald Trump to take a different approach on that issue.
With all that focus on the scope of the 2001 statute, the question arises: What about using force against a terrorist threat that is beyond the scope of the AUMF? Not every threat is organizationally linked to al Qaeda in the requisite way, after all. In such a case, the question becomes whether the use of force can be justified by the President’s own inherent authority under Article II of the Constitution. Obviously, it is more controversial for force to be based on inherent presidential authority instead of a statute, but there is widespread agreement that there is at least some such authority in circumstances of national self-defense.
The Bush Administration made a point of stating that its actions against al Qaeda were justified both by the AUMF and by Article II. The Obama Administration has gone out of its way to rely just on the AUMF without mentioning Article II as well, but it has not claimed affirmatively that Article II has no relevance. At any rate, the bottom line is that President-elect Trump almost certainly will be advised he is authorized under American law to use lethal force against a terrorist target, quite apart from the AUMF, at least if and when the target poses an imminent threat to American lives. Readers who want an accessible overview of this important question might find this essay helpful.
TCB: How are such strikes understood in accordance with the international laws of armed conflict?
BC: For 15 years, our position has been that there is a state of armed conflict that exists with al Qaeda and the Afghan Taliban (and its associated forces as noted above), and that the conflict is not limited to some particular location, such as Afghanistan. That no-geographic-limits claim has drawn lots of criticism, especially overseas. There are many who accept that the law of armed conflict applies (or applied) in Afghanistan and Iraq (and now Syria) but denied that it applied in other locations where the United States has captured or killed AQ members. Understanding that the U.S. government and its critics differ on this point is critical to appreciating why there seems to be so much disconnect in discussions of drone strikes and Guantanamo Bay (GTMO) terrorist detention facility.
At any rate, under the U.S. view, the law of armed conflict applies. What other issues then arise? The two biggest legal questions with targeting involve “distinction” and “proportionality.”
Distinction is the idea that you may target only combatants and not civilians, though civilians can waive their immunity for such time as they directly participate in hostilities. Sounds reasonably straightforward, doesn’t it? Unfortunately, applying this rule in a conflict with a non-state actor gets tricky. This is not a conflict between two states, with professional armed forces easily distinguished from civilian populations. Quite the contrary. And it turns out there is significant debate regarding the right way to categorize the members of a non-state actor that is a party to an armed conflict.
One view holds that all members of such a group count as combatants. At the other end of the spectrum, some argue that all of them are civilians (albeit dangerous ones). And there are middle-ground approaches, such as the International Committee of the Red Cross position, in which you may treat as a combatant the group members who have a “continuous combat function.”
During the Bush Administration, the U.S. government position was that all the members counted as combatants. The Obama Administration position is less clear to me, to be frank, in part because there have at times been favorable references to the “continuous combat function” approach, and in part because the administration, as a matter of policy, has stated its commitment to a more-constrained approach for operations outside of areas of active hostilities.
The other big issue is proportionality. This is where the collateral damage concept comes in. Sometimes it is foreseeable there will be harm to civilians incidental to an attack on a proper target. Proportionality does not forbid this, but it does require that the harm to civilians or civilian objects not be disproportionate to the military advantage to be gained from the attack.
The U.S. government and its critics have identified wildly different estimates of collateral damage from our counterterrorism strikes. What explains this? To some extent it’s fog of war, but I think the biggest confounding factor traces back to the “distinction” debate noted above: the U.S. government and its critics probably are not using the same definitions for who counts as a permissible target and who instead should be counted as collateral damage in the proportionality analysis.
TCB: Do foreign countries need to grant the U.S. permission to conduct drone strikes on their territory?
BC: The UN Charter—a treaty to which the United States is a party, of course—creates a default rule against the use of force in international affairs on the territory of another state and without that state’s consent. The idea is that a state may use force in such a situation only with the permission of the U.N. Security Council or when acting in self-defense under Article 51 of the Charter.
Most U.S. uses of force for “drone strikes” appear to be based on the consent of the host government. Such consent is quite clear in some cases, but less so in others, perhaps because the host state government has consented privately, but on condition that the consent not be acknowledged publicly.
Where there is no consent and no Security Council resolution, one might argue instead that the U.S. is acting under color of UN Charter Article 51’s self-defense rule. The problem with that line of argument is that the attacker giving rise to Article 51 rights—the terrorist group—is not the same thing as the state in whose territory we then propose to carry out a strike. Under the law of “state responsibility,” such a case can be made in the right circumstances, but there is a lot of room for disagreement in debating that issue.
Which brings us to the argument made most often by the United States apart from the consent argument: some governments are unable or unwilling to suppress attacks by terrorist organizations with havens within their borders. The U.S. government takes the view that, in such cases, the host-state government, in effect, has waived any objection to a necessary-and-proportionate Article 51 response against that terrorist group that takes place in its territory. This view has many critics, especially overseas, though those criticisms dropped off sharply after the Islamic State surged to prominence, and it became necessary to rely on this exact argument in order to justify use of force against the Islamic State inside Syrian territory without Syrian President Bashar al-Assad’s consent.
TCB: If a country denies permission, does that country have any legal recourse should the U.S. take action anyway?
BC: If the United States carries out a strike without consent, and the host state rejects the unwilling-unable argument described above, that host state naturally will lodge diplomatic objections and might attempt to bring other forms of pressure to bear on the United States. But given the imbalance of power between the United States and most states in which this situation might arise, such measures are unlikely to have significant impact.
If the host state wants to pursue a legal remedy, it is unlikely to get anywhere by trying to litigate in a U.S. court. The UN Security Council is a dead end, since the United States holds a veto there. The state might try to get the International Criminal Court, if that state is a party to it (the United States is not), or the ICC prosecutor’s office might even take up the question on its own initiative – as may be happening soon in relation to Afghanistan, according to some reports.
TCB: What are some of the biggest legal concerns surrounding the use of drones that remain unanswered? How do you see them evolving in the short-term?
BC: My list of the top legal points of friction, drawing on and adding to the points mentioned above, would include:
- Are there geographic limits on the armed conflict model?
- What is the right standard for identifying targetable combatants when fighting a non-state actor?
- Is the unwilling-unable test a proper interpretation of the UN Charter?
- Which groups, precisely, can fairly be said to be within the scope of the 2001 AUMF now that we are nearing 2017?
- Precisely when does the President have inherent power to use lethal force for counterterrorism under color of Article II standing alone?
There are plenty of additional hot-button issues, especially for the rare cases like Anwar al-Awlaki, where the target is known to be a U.S. citizen, thus implicating the Fifth Amendment Due Process Clause.
